TY - JOUR
A1 - Shi, Jun
A1 - Joshi, Jasmin Radha
A1 - Tielboerger, Katja
A1 - Verhoeven, Koen J. F.
A1 - Macel, Mirka
T1 - Costs and benefits of admixture between foreign genotypes and local populations in the field
JF - Ecology and evolution
N2 - Admixture is the hybridization between populations within one species. It can increase plant fitness and population viability by alleviating inbreeding depression and increasing genetic diversity. However, populations are often adapted to their local environments and admixture with distant populations could break down local adaptation by diluting the locally adapted genomes. Thus, admixed genotypes might be selected against and be outcompeted by locally adapted genotypes in the local environments. To investigate the costs and benefits of admixture, we compared the performance of admixed and within-population F1 and F2 generations of the European plant Lythrum salicaria in a reciprocal transplant experiment at three European field sites over a 2-year period. Despite strong differences between site and plant populations for most of the measured traits, including herbivory, we found limited evidence for local adaptation. The effects of admixture depended on experimental site and plant population, and were positive for some traits. Plant growth and fruit production of some populations increased in admixed offspring and this was strongest with larger parental distances. These effects were only detected in two of our three sites. Our results show that, in the absence of local adaptation, admixture may boost plant performance, and that this is particularly apparent in stressful environments. We suggest that admixture between foreign and local genotypes can potentially be considered in nature conservation to restore populations and/or increase population viability, especially in small inbred or maladapted populations.
KW - heterosis
KW - inbreeding depression
KW - local adaptation
KW - Lythrum salicaria
KW - outbreeding depression
Y1 - 2018
U6 - https://doi.org/10.1002/ece3.3946
SN - 2045-7758
VL - 8
IS - 7
SP - 3675
EP - 3684
PB - Wiley
CY - Hoboken
ER -
TY - JOUR
A1 - Ayllon, Daniel
A1 - Grimm, Volker
A1 - Attinger, Sabine
A1 - Hauhs, Michael
A1 - Simmer, Clemens
A1 - Vereecken, Harry
A1 - Lischeid, Gunnar
T1 - Cross-disciplinary links in environmental systems science
BT - Current state and claimed needs identified in a meta-review of process models
JF - The science of the total environment : an international journal for scientific research into the environment and its relationship with man
N2 - Terrestrial environmental systems are characterised by numerous feedback links between their different compartments. However, scientific research is organized into disciplines that focus on processes within the respective compartments rather than on interdisciplinary links. Major feedback mechanisms between compartments might therefore have been systematically overlooked so far. Without identifying these gaps, initiatives on future comprehensive environmental monitoring schemes and experimental platforms might fail. We performed a comprehensive overview of feedbacks between compartments currently represented in environmental sciences and explores to what degree missing links have already been acknowledged in the literature. We focused on process models as they can be regarded as repositories of scientific knowledge that compile findings of numerous single studies. In total, 118 simulation models from 23 model types were analysed. Missing processes linking different environmental compartments were identified based on a meta-review of 346 published reviews, model inter-comparison studies, and model descriptions. Eight disciplines of environmental sciences were considered and 396 linking processes were identified and ascribed to the physical, chemical or biological domain. There were significant differences between model types and scientific disciplines regarding implemented interdisciplinary links. The most wide-spread interdisciplinary links were between physical processes in meteorology, hydrology and soil science that drive or set the boundary conditions for other processes (e.g., ecological processes). In contrast, most chemical and biological processes were restricted to links within the same compartment. Integration of multiple environmental compartments and interdisciplinary knowledge was scarce in most model types. There was a strong bias of suggested future research foci and model extensions towards reinforcing existing interdisciplinary knowledge rather than to open up new interdisciplinary pathways. No clear pattern across disciplines exists with respect to suggested future research efforts. There is no evidence that environmental research would clearly converge towards more integrated approaches or towards an overarching environmental systems theory. (c) 2017 Elsevier B.V. All rights reserved.
KW - Review
KW - Interdisciplinary links
KW - Integrated environmental modelling
KW - Research needs
Y1 - 2018
U6 - https://doi.org/10.1016/j.scitotenv.2017.12.007
SN - 0048-9697
SN - 1879-1026
VL - 622
SP - 954
EP - 973
PB - Elsevier
CY - Amsterdam
ER -
TY - JOUR
A1 - Zhivkova, Veselina
A1 - Kiecker, Felix
A1 - Langer, Peter
A1 - Eberle, Jürgen
T1 - Crucial role of reactive oxygen species (ROS) for the proapoptotic effects of indirubin derivative DKP-073 in melanoma cells
JF - Molecular carcinogenesis
N2 - Melanoma represents a prime example demonstrating the success of targeted therapy in cancer. Nevertheless, it remained a deadly disease until now, and the identification of new, independent strategies as well as the understanding of their molecular mechanisms may help to finally overcome the high mortality. Both indirubins and TNF-related apoptosis-inducing ligand (TRAIL) represent promising candidates. Here, the indirubin derivative DKP-073 is shown to trigger apoptosis in melanoma cells, which is enhanced by the combination with TRAIL and is accompanied by complete loss of cell viability. Addressing the signaling cascade, characteristic molecular steps were identified as caspase-3 activation, downregulation of XIAP, upregulation of p53 and TRAIL receptor 2, loss of mitochondrial membrane potential, and STAT-3 dephosphorylation. The decisive step, however, turned out to be the early production of ROS already at 1 h. This was proven by antioxidant pretreatment, which completely abolished apoptosis induction and loss of cell viability as well as abrogated all signaling effects listed above. Thus, ROS appeared as upstream of all proapoptotic signaling. The data indicate a dominant role of ROS in apoptosis regulation, and the new pathway may expose a possible Achilles heel of melanoma.
KW - apoptosis
KW - kinase pathway
KW - melanoma
KW - stat 3
Y1 - 2018
U6 - https://doi.org/10.1002/mc.22924
SN - 0899-1987
SN - 1098-2744
VL - 58
IS - 2
SP - 258
EP - 269
PB - Wiley
CY - Hoboken
ER -
TY - JOUR
A1 - Beermann, Jan
A1 - Westbury, Michael V.
A1 - Hofreiter, Michael
A1 - Hilgers, Leon
A1 - Deister, Fabian
A1 - Neumann, Hermann
A1 - Raupach, Michael J.
T1 - Cryptic species in a well-known habitat
BT - applying taxonomics to the amphipod genus Epimeria (Crustacea, Peracarida)
JF - Scientific reports
N2 - Taxonomy plays a central role in biological sciences. It provides a communication system for scientists as it aims to enable correct identification of the studied organisms. As a consequence, species descriptions should seek to include as much available information as possible at species level to follow an integrative concept of 'taxonomics'. Here, we describe the cryptic species Epimeria frankei sp. nov. from the North Sea, and also redescribe its sister species, Epimeria cornigera. The morphological information obtained is substantiated by DNA barcodes and complete nuclear 18S rRNA gene sequences. In addition, we provide, for the first time, full mitochondrial genome data as part of a metazoan species description for a holotype, as well as the neotype. This study represents the first successful implementation of the recently proposed concept of taxonomics, using data from high-throughput technologies for integrative taxonomic studies, allowing the highest level of confidence for both biodiversity and ecological research.
Y1 - 2018
U6 - https://doi.org/10.1038/s41598-018-25225-x
SN - 2045-2322
VL - 8
PB - Nature Publ. Group
CY - London
ER -
TY - JOUR
A1 - Whitcomb, Sarah J.
A1 - Nguyen, Huu Cuong
A1 - Brückner, Franziska
A1 - Hesse, Holger
A1 - Hoefgen, Rainer
T1 - CYSTATHIONINE GAMMA-SYNTHASE activity in rice is developmentally regulated and strongly correlated with sulfate
JF - Plant science : an international journal of experimental plant biology
N2 - An important goal of rice cultivar development is improvement of protein quality, especially with respect to essential amino acids such as methionine. With the goal of increasing seed methionine content, we generated Oryza sativa ssp. japonica cv. Taipei 309 transgenic lines expressing a feedback-desensitized CYSTATHIONINE GAMMA-SYNTHASE from Arabidopsis thaliana (AtD-CGS) under the control of the maize ubiquitin promoter. Despite persistently elevated cystathionine gamma-synthase (CGS) activity in the AtD-CGS transgenic lines relative to untransformed Taipei, sulfate was the only sulfur-containing compound found to be elevated throughout vegetative development. Accumulation of methionine and other sulfur-containing metabolites was limited to the leaves of young plants. Sulfate concentration was found to strongly and positively correlate with CGS activity across vegetative development, irrespective of whether the activity was provided by the endogenous rice CGS or by a combination of endogenous and AtD-CGS. Conversely, the concentrations of glutathione, valine, and leucine were clearly negatively correlated with CGS activity in the same tissues. We also observed a strong decrease in CGS activity in both untransformed Taipei and the AtD-CGS transgenic lines as the plants approached heading stage. The mechanism for this downregulation is currently unknown and of potential importance for efforts to increase methionine content in rice.
KW - Aromatic amino acids
KW - AtD-CGS
KW - Branched chain amino acids
KW - CYSTATHIONINE GAMMA-SYNTHASE
KW - Glutathione
KW - Oryza sativa ssp japonica cv. taipei 309
KW - Sulfate
Y1 - 2018
U6 - https://doi.org/10.1016/j.plantsci.2018.02.016
SN - 0168-9452
VL - 270
SP - 234
EP - 244
PB - Elsevier
CY - Clare
ER -
TY - JOUR
A1 - Prahl, Boris F.
A1 - Boettle, Markus
A1 - Costa, Luís Fílípe Carvalho da
A1 - Kropp, Jürgen
A1 - Rybski, Diego
T1 - Damage and protection cost curves for coastal floods within the 600 largest European cities
JF - Scientific Data
N2 - The economic assessment of the impacts of storm surges and sea-level rise in coastal cities requires high-level information on the damage and protection costs associated with varying flood heights. We provide a systematically and consistently calculated dataset of macroscale damage and protection cost curves for the 600 largest European coastal cities opening the perspective for a wide range of applications. Offering the first comprehensive dataset to include the costs of dike protection, we provide the underpinning information to run comparative assessments of costs and benefits of coastal adaptation. Aggregate cost curves for coastal flooding at the city-level are commonly regarded as by-products of impact assessments and are generally not published as a standalone dataset. Hence, our work also aims at initiating a more critical discussion on the availability and derivation of cost curves.
Y1 - 2018
U6 - https://doi.org/10.1038/sdata.2018.34
SN - 2052-4463
VL - 5
PB - Nature Publ. Group
CY - London
ER -
TY - JOUR
A1 - Mantzouki, Evanthia
A1 - Campbell, James
A1 - van Loon, Emiel
A1 - Visser, Petra
A1 - Konstantinou, Iosif
A1 - Antoniou, Maria
A1 - Giuliani, Gregory
A1 - Machado-Vieira, Danielle
A1 - de Oliveira, Alinne Gurjao
A1 - Maronic, Dubravka Spoljaric
A1 - Stevic, Filip
A1 - Pfeiffer, Tanja Zuna
A1 - Vucelic, Itana Bokan
A1 - Zutinic, Petar
A1 - Udovic, Marija Gligora
A1 - Plenkovic-Moraj, Andelka
A1 - Tsiarta, Nikoletta
A1 - Blaha, Ludek
A1 - Geris, Rodan
A1 - Frankova, Marketa
A1 - Christoffersen, Kirsten Seestern
A1 - Warming, Trine Perlt
A1 - Feldmann, Tonu
A1 - Laas, Alo
A1 - Panksep, Kristel
A1 - Tuvikene, Lea
A1 - Kangro, Kersti
A1 - Haggqvist, Kerstin
A1 - Salmi, Pauliina
A1 - Arvola, Lauri
A1 - Fastner, Jutta
A1 - Straile, Dietmar
A1 - Rothhaupt, Karl-Otto
A1 - Fonvielle, Jeremy Andre
A1 - Grossart, Hans-Peter
A1 - Avagianos, Christos
A1 - Kaloudis, Triantafyllos
A1 - Triantis, Theodoros
A1 - Zervou, Sevasti-Kiriaki
A1 - Hiskia, Anastasia
A1 - Gkelis, Spyros
A1 - Panou, Manthos
A1 - McCarthy, Valerie
A1 - Perello, Victor C.
A1 - Obertegger, Ulrike
A1 - Boscaini, Adriano
A1 - Flaim, Giovanna
A1 - Salmaso, Nico
A1 - Cerasino, Leonardo
A1 - Koreiviene, Judita
A1 - Karosiene, Jurate
A1 - Kasperoviciene, Jurate
A1 - Savadova, Ksenija
A1 - Vitonyte, Irma
A1 - Haande, Sigrid
A1 - Skjelbred, Birger
A1 - Grabowska, Magdalena
A1 - Karpowicz, Maciej
A1 - Chmura, Damian
A1 - Nawrocka, Lidia
A1 - Kobos, Justyna
A1 - Mazur-Marzec, Hanna
A1 - Alcaraz-Parraga, Pablo
A1 - Wilk-Wozniak, Elzbieta
A1 - Krzton, Wojciech
A1 - Walusiak, Edward
A1 - Gagala, Ilona
A1 - Mankiewicz-Boczek, Joana
A1 - Toporowska, Magdalena
A1 - Pawlik-Skowronska, Barbara
A1 - Niedzwiecki, Michal
A1 - Peczula, Wojciech
A1 - Napiorkowska-Krzebietke, Agnieszka
A1 - Dunalska, Julita
A1 - Sienska, Justyna
A1 - Szymanski, Daniel
A1 - Kruk, Marek
A1 - Budzynska, Agnieszka
A1 - Goldyn, Ryszard
A1 - Kozak, Anna
A1 - Rosinska, Joanna
A1 - Szelag-Wasielewska, Elzbieta
A1 - Domek, Piotr
A1 - Jakubowska-Krepska, Natalia
A1 - Kwasizur, Kinga
A1 - Messyasz, Beata
A1 - Pelechata, Aleksandra
A1 - Pelechaty, Mariusz
A1 - Kokocinski, Mikolaj
A1 - Madrecka, Beata
A1 - Kostrzewska-Szlakowska, Iwona
A1 - Frak, Magdalena
A1 - Bankowska-Sobczak, Agnieszka
A1 - Wasilewicz, Michal
A1 - Ochocka, Agnieszka
A1 - Pasztaleniec, Agnieszka
A1 - Jasser, Iwona
A1 - Antao-Geraldes, Ana M.
A1 - Leira, Manel
A1 - Hernandez, Armand
A1 - Vasconcelos, Vitor
A1 - Morais, Joao
A1 - Vale, Micaela
A1 - Raposeiro, Pedro M.
A1 - Goncalves, Vitor
A1 - Aleksovski, Boris
A1 - Krstic, Svetislav
A1 - Nemova, Hana
A1 - Drastichova, Iveta
A1 - Chomova, Lucia
A1 - Remec-Rekar, Spela
A1 - Elersek, Tina
A1 - Delgado-Martin, Jordi
A1 - Garcia, David
A1 - Luis Cereijo, Jose
A1 - Goma, Joan
A1 - Carmen Trapote, Mari
A1 - Vegas-Vilarrubia, Teresa
A1 - Obrador, Biel
A1 - Garcia-Murcia, Ana
A1 - Real, Monserrat
A1 - Romans, Elvira
A1 - Noguero-Ribes, Jordi
A1 - Parreno Duque, David
A1 - Fernandez-Moran, Elisabeth
A1 - Ubeda, Barbara
A1 - Angel Galvez, Jose
A1 - Marce, Rafael
A1 - Catalan, Nuria
A1 - Perez-Martinez, Carmen
A1 - Ramos-Rodriguez, Eloisa
A1 - Cillero-Castro, Carmen
A1 - Moreno-Ostos, Enrique
A1 - Maria Blanco, Jose
A1 - Rodriguez, Valeriano
A1 - Juan Montes-Perez, Jorge
A1 - Palomino, Roberto L.
A1 - Rodriguez-Perez, Estela
A1 - Carballeira, Rafael
A1 - Camacho, Antonio
A1 - Picazo, Antonio
A1 - Rochera, Carlos
A1 - Santamans, Anna C.
A1 - Ferriol, Carmen
A1 - Romo, Susana
A1 - Soria, Juan Miguel
A1 - Hansson, Lars-Anders
A1 - Urrutia-Cordero, Pablo
A1 - Ozen, Arda
A1 - Bravo, Andrea G.
A1 - Buck, Moritz
A1 - Colom-Montero, William
A1 - Mustonen, Kristiina
A1 - Pierson, Don
A1 - Yang, Yang
A1 - Verspagen, Jolanda M. H.
A1 - Domis, Lisette N. de Senerpont
A1 - Seelen, Laura
A1 - Teurlincx, Sven
A1 - Verstijnen, Yvon
A1 - Lurling, Miquel
A1 - Maliaka, Valentini
A1 - Faassen, Elisabeth J.
A1 - Latour, Delphine
A1 - Carey, Cayelan C.
A1 - Paerl, Hans W.
A1 - Torokne, Andrea
A1 - Karan, Tunay
A1 - Demir, Nilsun
A1 - Beklioglu, Meryem
A1 - Filiz, Nur
A1 - Levi, Eti E.
A1 - Iskin, Ugur
A1 - Bezirci, Gizem
A1 - Tavsanoglu, Ulku Nihan
A1 - Celik, Kemal
A1 - Ozhan, Koray
A1 - Karakaya, Nusret
A1 - Kocer, Mehmet Ali Turan
A1 - Yilmaz, Mete
A1 - Maraslioglu, Faruk
A1 - Fakioglu, Ozden
A1 - Soylu, Elif Neyran
A1 - Yagci, Meral Apaydin
A1 - Cinar, Sakir
A1 - Capkin, Kadir
A1 - Yagci, Abdulkadir
A1 - Cesur, Mehmet
A1 - Bilgin, Fuat
A1 - Bulut, Cafer
A1 - Uysal, Rahmi
A1 - Koker, Latife
A1 - Akcaalan, Reyhan
A1 - Albay, Meric
A1 - Alp, Mehmet Tahir
A1 - Ozkan, Korhan
A1 - Sevindik, Tugba Ongun
A1 - Tunca, Hatice
A1 - Onem, Burcin
A1 - Richardson, Jessica
A1 - Edwards, Christine
A1 - Bergkemper, Victoria
A1 - Beirne, Eilish
A1 - Cromie, Hannah
A1 - Ibelings, Bastiaan W.
T1 - Data Descriptor: A European Multi Lake Survey dataset of environmental variables, phytoplankton pigments and cyanotoxins
JF - Scientific Data
N2 - Under ongoing climate change and increasing anthropogenic activity, which continuously challenge ecosystem resilience, an in-depth understanding of ecological processes is urgently needed. Lakes, as providers of numerous ecosystem services, face multiple stressors that threaten their functioning. Harmful cyanobacterial blooms are a persistent problem resulting from nutrient pollution and climate-change induced stressors, like poor transparency, increased water temperature and enhanced stratification. Consistency in data collection and analysis methods is necessary to achieve fully comparable datasets and for statistical validity, avoiding issues linked to disparate data sources. The European Multi Lake Survey (EMLS) in summer 2015 was an initiative among scientists from 27 countries to collect and analyse lake physical, chemical and biological variables in a fully standardized manner. This database includes in-situ lake variables along with nutrient, pigment and cyanotoxin data of 369 lakes in Europe, which were centrally analysed in dedicated laboratories. Publishing the EMLS methods and dataset might inspire similar initiatives to study across large geographic areas that will contribute to better understanding lake responses in a changing environment.
KW - Climate-change ecology
KW - Limnology
KW - Water resources
Y1 - 2018
U6 - https://doi.org/10.1038/sdata.2018.226
SN - 2052-4463
VL - 5
PB - Nature Publ. Group
CY - London
ER -
TY - JOUR
A1 - Schwahn, Kevin
A1 - Nikoloski, Zoran
T1 - Data reduction approaches for dissecting transcriptional effects on metabolism
JF - Frontiers in plant science
N2 - The availability of high-throughput data from transcriptomics and metabolomics technologies provides the opportunity to characterize the transcriptional effects on metabolism. Here we propose and evaluate two computational approaches rooted in data reduction techniques to identify and categorize transcriptional effects on metabolism by combining data on gene expression and metabolite levels. The approaches determine the partial correlation between two metabolite data profiles upon control of given principal components extracted from transcriptomics data profiles. Therefore, they allow us to investigate both data types with all features simultaneously without doing preselection of genes. The proposed approaches allow us to categorize the relation between pairs of metabolites as being under transcriptional or post-transcriptional regulation. The resulting classification is compared to existing literature and accumulated evidence about regulatory mechanism of reactions and pathways in the cases of Escherichia coil, Saccharomycies cerevisiae, and Arabidopsis thaliana.
KW - E. coil
KW - S. cerevisiae
KW - A. thaliana
KW - partial correlation
KW - principal component analysis
KW - metabolomics
KW - data reduction
KW - regulation
Y1 - 2018
U6 - https://doi.org/10.3389/fpls.2018.00538
SN - 1664-462X
VL - 9
PB - Frontiers Research Foundation
CY - Lausanne
ER -
TY - JOUR
A1 - Wutke, Saskia
A1 - Sandoval-Castellanos, Edson
A1 - Benecke, Norbert
A1 - Döhle, Hans-Jürgen
A1 - Friederich, Susanne
A1 - Gonzalez, Javier
A1 - Hofreiter, Michael
A1 - Lougas, Lembi
A1 - Magnell, Ola
A1 - Malaspinas, Anna-Sapfo
A1 - Morales-Muniz, Arturo
A1 - Orlando, Ludovic
A1 - Reissmann, Monika
A1 - Trinks, Alexandra
A1 - Ludwig, Arne
T1 - Decline of genetic diversity in ancient domestic stallions in Europe
JF - Science Advances
N2 - Present-day domestic horses are immensely diverse in their maternally inherited mitochondrial DNA, yet they show very little variation on their paternally inherited Y chromosome. Although it has recently been shown that Y chromosomal diversity in domestic horses was higher at least until the Iron Age, when and why this diversity disappeared remain controversial questions. We genotyped 16 recently discovered Y chromosomal single-nucleotide polymorphisms in 96 ancient Eurasian stallions spanning the early domestication stages (Copper and Bronze Age) to the Middle Ages. Using this Y chromosomal time series, which covers nearly the entire history of horse domestication, we reveal how Y chromosomal diversity changed over time. Our results also show that the lack of multiple stallion lineages in the extant domestic population is caused by neither a founder effect nor random demographic effects but instead is the result of artificial selection-initially during the Iron Age by nomadic people from the Eurasian steppes and later during the Roman period. Moreover, the modern domestic haplotype probably derived from another, already advantageous, haplotype, most likely after the beginning of the domestication. In line with recent findings indicating that the Przewalski and domestic horse lineages remained connected by gene flow after they diverged about 45,000 years ago, we present evidence for Y chromosomal introgression of Przewalski horses into the gene pool of European domestic horses at least until medieval times.
Y1 - 2018
U6 - https://doi.org/10.1126/sciadv.aap9691
SN - 2375-2548
VL - 4
IS - 4
PB - American Assoc. for the Advancement of Science
CY - Washington
ER -
TY - JOUR
A1 - Spijkerman, Elly
A1 - Behrend, Hella
A1 - Fach, Bettina
A1 - Gaedke, Ursula
T1 - Decreased phosphorus incorporation explains the negative effect of high iron concentrations in the green microalga Chlamydomonas acidophila
JF - The science of the total environment : an international journal for scientific research into the environment and its relationship with man
N2 - The green microalga Chlamydomonas acidophila is an important primary producer in very acidic lakes (pH 2.0-3.5), characterized by high concentrations of ferric iron (up to 1 g total Fe L-1) and low rates of primary production. It was previously suggested that these high iron concentrations result in high iron accumulation and inhibit photosynthesis in C. acidophila. To test this, the alga was grown in sterilized lake water and in medium with varying total iron concentrations under limiting and sufficient inorganic phosphorus (Pi) supply, because Pi is an important growth limiting nutrient in acidic waters. Photosynthesis and growth of C. acidophila as measured over 5 days were largely unaffected by high total iron concentrations and only decreased if free ionic Fe3+ concentrations exceeded 100 mg Fe3+ L-1. Although C. acidophila was relatively rich in iron (up to 5 mmol Fe: mol C), we found no evidence of iron toxicity. In contrast, a concentration of 260 mg total Fe L-1 (i.e. 15 mg free ionic Fe3+ L-1), which is common in many acidic lakes, reduced Pi-incorporation by 50% and will result in Pi-limited photosynthesis. The resulting Pi-limitation present at high iron and Pi concentrations was illustrated by elevated maximum Pi-uptake rates. No direct toxic effects of high iron were found, but unfavourable chemical Pi-speciation reduced growth of the acidophile alga.
KW - Chlamydomonas
KW - Ecotoxicology
KW - Extreme environment
KW - Iron toxicity
KW - Phosphate limitation
KW - Phytoplankton
Y1 - 2018
U6 - https://doi.org/10.1016/j.scitotenv.2018.01.188
SN - 0048-9697
SN - 1879-1026
VL - 626
SP - 1342
EP - 1349
PB - Elsevier
CY - Amsterdam
ER -
TY - THES
A1 - Schöne, Anne-Christin
T1 - Degradation of Aliphatic Polyesters at the Air-Water Interface - Capabilities of the Langmuir Monolayer Technique
Y1 - 2018
ER -
TY - THES
A1 - Schwanhold, Nadine
T1 - Die Funktion und Spezifität der Molybdän-Cofaktor-bindenden Chaperone für die Formiat-Dehydrogenasen aus Escherichia coli und Rhodobacter capsulatus
Y1 - 2018
ER -
TY - JOUR
A1 - Laux, Eva-Maria
A1 - Ermilova, Elena
A1 - Pannwitz, Daniel
A1 - Gibbons, Jessica
A1 - Hölzel, Ralph
A1 - Bier, Frank Fabian
T1 - Dielectric Spectroscopy of Biomolecules up to 110 GHz
JF - Frequenz
N2 - Radio-frequency fields in the GHz range are increasingly applied in biotechnology and medicine. In order to fully exploit both their potential and their risks detailed information about the dielectric properties of biological material is needed. For this purpose a measuring system is presented that allows the acquisition of complex dielectric spectra over 4 frequency decade up to 110 GHz. Routines for calibration and for data evaluation according to physicochemical interaction models have been developed. The frequency dependent permittivity and dielectric loss of some proteins and nucleic acids, the main classes of biomolecules, and of their sub-units have been determined. Dielectric spectra are presented for the amino acid alanine, the proteins lysozyme and haemoglobin, the nucleotides AMP and ATP, and for the plasmid pET-21, which has been produced by bacterial culture. Characterisation of a variety of biomolecules is envisaged, as is the application to studies on protein structure and function.
KW - dielectric
KW - spectroscopy
KW - permittivity
KW - protein
KW - DNA
KW - amino acid
KW - plasmid
Y1 - 2018
U6 - https://doi.org/10.1515/freq-2018-0010
SN - 0016-1136
SN - 2191-6349
VL - 72
IS - 3-4
SP - 135
EP - 140
PB - De Gruyter
CY - Berlin
ER -
TY - JOUR
A1 - Laux, Eva-Maria
A1 - Bier, Frank Fabian
A1 - Hölzel, Ralph
T1 - Dielectrophoretic Stretching of DNA
JF - DNA Nanotechnology
N2 - The spatial control of DNA and of self-assembled DNA constructs is a prerequisite for the preparation of DNA-based nanostructures and microstructures and a useful tool for studies on single DNA molecules. Here we describe a protocol for the accumulation of dissolved lambda-DNA molecules between planar microelectrodes by the action of inhomogeneous radiofrequency electric fields. The resulting AC electrokinetic forces stretch the DNA molecules and align them parallel to the electric field. The electrode preparation from off-the-shelf electronic components is explained, and a detailed description of the electronic setup is given. The experimental procedure is controlled in real-time by fluorescence microscopy.
KW - Alignment
KW - Dielectrophoresis
KW - DNA
KW - Electrokinetics
KW - Interdigitated electrodes
KW - Stretching
Y1 - 2018
SN - 978-1-4939-8582-1
SN - 978-1-4939-8581-4
U6 - https://doi.org/10.1007/978-1-4939-8582-1_14
SN - 1064-3745
SN - 1940-6029
SP - 199
EP - 208
PB - Humana Press Inc.
CY - New York
ET - 2
ER -
TY - JOUR
A1 - Weyrich, Alexandra
A1 - Jeschek, Marie
A1 - Schrapers, Katharina T.
A1 - Lenz, Dorina
A1 - Chung, Tzu Hung
A1 - Ruebensam, Kathrin
A1 - Yasar, Sermin
A1 - Schneemann, Markus
A1 - Ortmann, Sylvia
A1 - Jewgenow, Katarina
A1 - Fickel, Jörns
T1 - Diet changes alter paternally inherited epigenetic pattern in male Wild guinea pigs
JF - Environmental Epigenetics
N2 - Epigenetic modifications, of which DNA methylation is the most stable, are a mechanism conveying environmental information to subsequent generations via parental germ lines. The paternal contribution to adaptive processes in the offspring might be crucial, but has been widely neglected in comparison to the maternal one. To address the paternal impact on the offspring’s adaptability to changes in diet composition, we investigated if low protein diet (LPD) in F0 males caused epigenetic alterations in their subsequently sired sons. We therefore fed F0 male Wild guinea pigs with a diet lowered in protein content (LPD) and investigated DNA methylation in sons sired before and after their father’s LPD treatment in both, liver and testis tissues. Our results point to a ‘heritable epigenetic response’ of the sons to the fathers’ dietary change. Because we detected methylation changes also in the testis tissue, they are likely to be transmitted to the F2 generation. Gene-network analyses of differentially methylated genes in liver identified main metabolic pathways indicating a metabolic reprogramming (‘metabolic shift’). Epigenetic mechanisms, allowing an immediate and inherited adaptation may thus be important for the survival of species in the context of a persistently changing environment, such as climate change.
KW - DNA methylation
KW - exposure
KW - wild mammal species
KW - inheritance
KW - plasticity
KW - adaptation
Y1 - 2018
U6 - https://doi.org/10.1093/eep/dvy011
SN - 2058-5888
VL - 4
IS - 2
PB - Oxford Univ. Press
CY - Oxford
ER -
TY - JOUR
A1 - Laeger, Thomas
A1 - Castano-Martinez, Teresa
A1 - Werno, Martin W.
A1 - Japtok, Lukasz
A1 - Baumeier, Christian
A1 - Jonas, Wenke
A1 - Kleuser, Burkhard
A1 - Schürmann, Annette
T1 - Dietary carbohydrates impair the protective effect of protein restriction against diabetes in NZO mice used as a model of type 2 diabetes
JF - Diabetologia : journal of the European Association for the Study of Diabetes (EASD)
N2 - Aims/hypothesis Low-protein diets are well known to improve glucose tolerance and increase energy expenditure. Increases in circulating fibroblast growth factor 21 (FGF21) have been implicated as a potential underlying mechanism. Methods We aimed to test whether low-protein diets in the context of a high-carbohydrate or high-fat regimen would also protect against type 2 diabetes in New Zealand Obese (NZO) mice used as a model of polygenetic obesity and type 2 diabetes. Mice were placed on high-fat diets that provided protein at control (16 kJ%; CON) or low (4 kJ%; low-protein/high-carbohydrate [LP/HC] or low-protein/high-fat [LP/HF]) levels. Results Protein restriction prevented the onset of hyperglycaemia and beta cell loss despite increased food intake and fat mass. The effect was seen only under conditions of a lower carbohydrate/fat ratio (LP/HF). When the carbohydrate/fat ratio was high (LP/HC), mice developed type 2 diabetes despite the robustly elevated hepatic FGF21 secretion and increased energy expenditure. Conclusion/interpretation Prevention of type 2 diabetes through protein restriction, without lowering food intake and body fat mass, is compromised by high dietary carbohydrates. Increased FGF21 levels and elevated energy expenditure do not protect against hyperglycaemia and type 2 diabetes per se.
KW - Energy expenditure
KW - FGF21
KW - Hyperglycaemia
KW - Insulin resistance
KW - NZO
KW - Obesity
KW - Protein restriction
Y1 - 2018
U6 - https://doi.org/10.1007/s00125-018-4595-1
SN - 0012-186X
SN - 1432-0428
VL - 61
IS - 6
SP - 1459
EP - 1469
PB - Springer
CY - New York
ER -
TY - JOUR
A1 - Paraskevopoulou, Sofia
A1 - Tiedemann, Ralph
A1 - Weithoff, Guntram
T1 - Differential response to heat stress among evolutionary lineages of an aquatic invertebrate species complex
JF - Biology letters
N2 - Under global warming scenarios, rising temperatures can constitute heat stress to which species may respond differentially. Within a described species, knowledge on cryptic diversity is of further relevance, as different lineages/cryptic species may respond differentially to environmental change. The Brachionus calyciflorus species complex (Rotifera), which was recently described using integrative taxonomy, is an essential component of aquatic ecosystems. Here, we tested the hypothesis that these (formerly cryptic) species differ in their heat tolerance. We assigned 47 clones with nuclear ITS1 (nuITS1) and mitochondrial COI (mtCOI) markers to evolutionary lineages, now named B. calyciflorus sensu stricto (s.s.) and B. fernandoi. We selected 15 representative clones and assessed their heat tolerance as a bi-dimensional phenotypic trait affected by both the intensity and duration of heat stress. We found two distinct groups, with B. calyciflorus s.s. clones having higher heat tolerance than the novel species B. fernandoi. This apparent temperature specialization among former cryptic species underscores the necessity of a sound species delimitation and assignment, when organismal responses to environmental changes are investigated.
KW - Brachionus calyciflorus
KW - critical thermal maximum
KW - cryptic species
KW - ecological speciation
KW - rotifers
KW - heat tolerance
Y1 - 2018
U6 - https://doi.org/10.1098/rsbl.2018.0498
SN - 1744-9561
SN - 1744-957X
VL - 14
IS - 11
PB - Royal Society
CY - London
ER -
TY - JOUR
A1 - Heger, Tina
A1 - Nikles, Gabriele
A1 - Jacobs, Brooke S.
T1 - Differentiation in native as well as introduced ranges
BT - germination reflects mean and variance in cover of surrounding vegetation
JF - AoB PLANTS
N2 - Germination, a crucial phase in the life cycle of a plant, can be significantly influenced by competition and facilitation. The aim of this study was to test whether differences in cover of surrounding vegetation can lead to population differentiation in germination behaviour of an annual grassland species, and if so, whether such a differentiation can be found in the native as well as in the introduced range. We used maternal progeny of Erodium cicutarium previously propagated under uniform conditions that had been collected in multiple populations in the native and two introduced ranges, in populations representing extremes in terms of mean and variability of the cover of surrounding vegetation. In the first experiment, we tested the effect of germination temperature and mean cover at the source site on germination, and found interlinked effects of these factors. In seeds from one of the introduced ranges (California), we found indication for a 2-fold dormancy, hindering germination at high temperatures even if physical dormancy was broken and water was available. This behaviour was less strong in high cover populations, indicating cross-generational facilitating effects of dense vegetation. In the second experiment, we tested whether spatial variation in cover of surrounding vegetation has an effect on the proportion of dormant seeds. Contrary to our expectations, we found that across source regions, high variance in cover was associated with higher proportions of seeds germinating directly after storage. In all three regions, germination seemed to match the local environment in terms of climate and vegetation cover. We suggest that this is due to a combined effect of introduction of preadapted genotypes and local evolutionary processes.
KW - Bet-hedging
KW - competition
KW - eco-evolutionary experience
KW - facilitation
KW - genetic adaptation
KW - physical and physiological dormancy
KW - preadaptation
Y1 - 2018
U6 - https://doi.org/10.1093/aobpla/ply009
SN - 2041-2851
VL - 10
IS - 1
PB - Oxford Univ. Press
CY - Oxford
ER -
TY - JOUR
A1 - Olmer, Ruth
A1 - Engels, Lena
A1 - Usman, Abdulai
A1 - Menke, Sandra
A1 - Malik, Muhammad Nasir Hayat
A1 - Pessler, Frank
A1 - Goehring, Gudrun
A1 - Bornhorst, Dorothee
A1 - Bolten, Svenja
A1 - Abdelilah-Seyfried, Salim
A1 - Scheper, Thomas
A1 - Kempf, Henning
A1 - Zweigerdt, Robert
A1 - Martin, Ulrich
T1 - Differentiation of Human Pluripotent Stem Cells into Functional Endothelial Cells in Scalable Suspension Culture
JF - Stem Cell Reports
N2 - Endothelial cells (ECs) are involved in a variety of cellular responses. As multifunctional components of vascular structures, endothelial (progenitor) cells have been utilized in cellular therapies and are required as an important cellular component of engineered tissue constructs and in vitro disease models. Although primary ECs from different sources are readily isolated and expanded, cell quantity and quality in terms of functionality and karyotype stability is limited. ECs derived from human induced pluripotent stem cells (hiPSCs) represent an alternative and potentially superior cell source, but traditional culture approaches and 2D differentiation protocols hardly allow for production of large cell numbers. Aiming at the production of ECs, we have developed a robust approach for efficient endothelial differentiation of hiPSCs in scalable suspension culture. The established protocol results in relevant numbers of ECs for regenerative approaches and industrial applications that show in vitro proliferation capacity and a high degree of chromosomal stability.
KW - virus infection
KW - progenitor cells
KW - in vitro
KW - telomere dysfunction
KW - cord blood
KW - cardiomyogenic differentiation
KW - angiogenesis
KW - efficient
KW - aberrations
KW - expression
Y1 - 2017
U6 - https://doi.org/10.1016/j.stemcr.2018.03.017
SN - 2213-6711
VL - 10
IS - 5
PB - Springer
CY - New York
ER -
TY - JOUR
A1 - Küçükgöze, Gökhan
A1 - Leimkühler, Silke
T1 - Direct comparison of the four aldehyde oxidase enzymes present in mouse gives insight into their substrate specificities
JF - PLOS ONE
N2 - Mammalian aldehyde oxidases (AOXs) are molybdo-flavoenzymes which are present in many tissues in various mammalian species, including humans and rodents. Different species contain a different number of AOX isoforms. In particular, the reasons why mammals other than humans express a multiplicity of tissue-specific AOX enzymes is unknown. In mouse, the isoforms mAOX1, mAOX3, mAOX4 and mAOX2 are present. We previously established a codon-optimized heterologous expression systems for the mAOX1-4 isoforms in Escherichia coli that gives yield to sufficient amounts of active protein for kinetic characterizations and sets the basis in this study for site-directed mutagenesis and structure-function studies. A direct and simultaneous comparison of the enzymatic properties and characteristics of the four enzymes on a larger number of substrates has never been performed. Here, thirty different structurally related aromatic, aliphatic and N-heterocyclic compounds were used as substrates, and the kinetic parameters of all four mAOX enzymes were directly compared. The results show that especially mAOX4 displays a higher substrate selectivity, while no major differences between mAOX1, mAOX2 and mAOX3 were identified. Generally, mAOX1 was the enzyme with the highest catalytic turnover for most substrates. To understand the factors that contribute to the substrate specificity of mAOX4, site-directed mutagenesis was applied to substitute amino acids in the substrate-binding funnel by the ones present in mAOX1, mAOX3, and mAOX2. An increase in activity was obtained by the amino acid exchange M1088V in the active site identified to be specific for mAOX4, to the amino acid identified in mAOX3.
Y1 - 2018
U6 - https://doi.org/10.1371/journal.pone.0191819
SN - 1932-6203
VL - 13
IS - 1
PB - Public Library of Science
CY - San Fransisco
ER -
TY - GEN
A1 - Dunsing, Valentin
A1 - Magnus, Mayer
A1 - Liebsch, Filip
A1 - Multhaup, Gerhard
A1 - Chiantia, Salvatore
T1 - Direct Evidence of APLP1 Trans Interactions in Cell-Cell Adhesion Platforms Investigated via Fluorescence Fluctuation Spectroscopy
T2 - Biophysical journal
N2 - The Amyloid-precursor-like protein 1 (APLP1) is a neuronal type I transmembrane protein which plays a role in synaptic adhesion and synaptogenesis. Past investigations indicated that APLP1 is involved in the formation of protein-protein complexes that bridge the junctions between neighboring cells. Nevertheless, APLP1-APLP1 trans interactions have never been directly observed in higher eukaryotic cells. Here, we investigate APLP1 interactions and dynamics directly in living human embryonic kidney (HEK) cells, using fluorescence fluctuation spectroscopy techniques, namely cross-correlation scanning fluorescence correlation spectroscopy (sFCS) and Number&Brightness (N&B). Our results show that APLP1 forms homotypic trans complexes at cell-cell contacts. In the presence of zinc ions, the protein forms macroscopic clusters, exhibiting an even higher degree of trans binding and strongly reduced dynamics. Further evidence from Giant Plasma Membrane Vesicles and live cell actin staining suggests that the presence of an intact cortical cytoskeleton is required for zinc-induced cis multimerization. Subsequently, large adhesion platforms bridging interacting cells are formed through APLP1-APLP1 direct trans interactions. Taken together, our results provide direct evidence that APLP1 functions as a neuronal zinc-dependent adhesion protein and provide a more detailed understanding of the molecular mechanisms driving the formation of APLP1 adhesion platforms. Further, they show that fluorescence fluctuation spectroscopy techniques are useful tools for the investigation of protein-protein interactions at cell-cell adhesion sites.
Y1 - 2018
U6 - https://doi.org/10.1016/j.bpj.2017.11.2067
SN - 0006-3495
SN - 1542-0086
VL - 114
IS - 3
SP - 373A
EP - 373A
PB - Cell Press
CY - Cambridge
ER -
TY - JOUR
A1 - Liu, Hsiang-chin
A1 - Lämke, Jörn
A1 - Lin, Siou-ying
A1 - Hung, Meng-Ju
A1 - Liu, Kuan-Ming
A1 - Charng, Yee-yung
A1 - Bäurle, Isabel
T1 - Distinct heat shock factors and chromatin modifications mediate the organ-autonomous transcriptional memory of heat stress
JF - The plant journal
N2 - Plants can be primed by a stress cue to mount a faster or stronger activation of defense mechanisms upon subsequent stress. A crucial component of such stress priming is the modified reactivation of genes upon recurring stress; however, the underlying mechanisms of this are poorly understood. Here, we report that dozens of Arabidopsis thaliana genes display transcriptional memory, i.e. stronger upregulation after a recurring heat stress, that lasts for at least 3 days. We define a set of transcription factors involved in this memory response and show that the transcriptional memory results in enhanced transcriptional activation within minutes of the onset of a heat stress cue. Further, we show that the transcriptional memory is active in all tissues. It may last for up to a week, and is associated during this time with histone H3 lysine 4 hypermethylation. This transcriptional memory is cis-encoded, as we identify a promoter fragment that confers memory onto a heterologous gene. In summary, heat-induced transcriptional memory is a widespread and sustained response, and our study provides a framework for future mechanistic studies of somatic stress memory in higher plants.
KW - epigenetics
KW - priming
KW - heat stress
KW - H3K4 methylation
KW - transcriptional memory
KW - Arabidopsis thaliana
KW - HSF
Y1 - 2018
U6 - https://doi.org/10.1111/tpj.13958
SN - 0960-7412
SN - 1365-313X
VL - 95
IS - 3
SP - 401
EP - 413
PB - Wiley
CY - Hoboken
ER -
TY - JOUR
A1 - Kolora, Sree Rohit Raj
A1 - Weigert, Anne
A1 - Saffari, Amin
A1 - Kehr, Stephanie
A1 - Walter Costa, Maria Beatriz
A1 - Spröer, Cathrin
A1 - Indrischek, Henrike
A1 - Chintalapati, Manjusha
A1 - Lohse, Konrad
A1 - Doose, Gero
A1 - Overmann, Jörg
A1 - Bunk, Boyke
A1 - Bleidorn, Christoph
A1 - Grimm-Seyfarth, Annegret
A1 - Henle, Klaus
A1 - Nowick, Katja
A1 - Faria, Rui
A1 - Stadler, Peter F.
A1 - Schlegel, Martin
T1 - Divergent evolution in the genomes of closely related lacertids, Lacerta viridis and L. bilineata, and implications for speciation
JF - GigaScience
N2 - Background Lacerta viridis and Lacerta bilineata are sister species of European green lizards (eastern and western clades, respectively) that, until recently, were grouped together as the L. viridis complex. Genetic incompatibilities were observed between lacertid populations through crossing experiments, which led to the delineation of two separate species within the L. viridis complex. The population history of these sister species and processes driving divergence are unknown. We constructed the first high-quality de novo genome assemblies for both L. viridis and L. bilineata through Illumina and PacBio sequencing, with annotation support provided from transcriptome sequencing of several tissues. To estimate gene flow between the two species and identify factors involved in reproductive isolation, we studied their evolutionary history, identified genomic rearrangements, detected signatures of selection on non-coding RNA, and on protein-coding genes. Findings Here we show that gene flow was primarily unidirectional from L. bilineata to L. viridis after their split at least 1.15 million years ago. We detected positive selection of the non-coding repertoire; mutations in transcription factors; accumulation of divergence through inversions; selection on genes involved in neural development, reproduction, and behavior, as well as in ultraviolet-response, possibly driven by sexual selection, whose contribution to reproductive isolation between these lacertid species needs to be further evaluated. Conclusion The combination of short and long sequence reads resulted in one of the most complete lizard genome assemblies. The characterization of a diverse array of genomic features provided valuable insights into the demographic history of divergence among European green lizards, as well as key species differences, some of which are candidates that could have played a role in speciation. In addition, our study generated valuable genomic resources that can be used to address conservation-related issues in lacertids.
KW - sister species
KW - PacBio and Illumina
KW - de novo hybrid assembly
KW - transcripts
KW - noncoding RNA
KW - zinc fingers
KW - positive selection
KW - UV response
KW - inversions
KW - gene flow
Y1 - 2018
U6 - https://doi.org/10.1093/gigascience/giy160
SN - 2047-217X
VL - 8
IS - 2
PB - Oxford Univ. Press
CY - Oxford
ER -
TY - JOUR
A1 - Van den Wyngaert, Silke
A1 - Rojas-Jimenez, Keilor
A1 - Seto, Kensuke
A1 - Kagami, Maiko
A1 - Grossart, Hans-Peter
T1 - Diversity and Hidden Host Specificity of Chytrids Infecting Colonial Volvocacean Algae
JF - Journal of Eukaryotic Microbiology
N2 - Chytrids are zoosporic fungi that play an important, but yet understudied, ecological role in aquatic ecosystems. Many chytrid species have been morphologically described as parasites on phytoplankton. However, the majority of them have rarely been isolated and lack DNA sequence data. In this study we isolated and cultivated three parasitic chytrids, infecting a common volvocacean host species, Yamagishiella unicocca. To identify the chytrids, we characterized morphology and life cycle, and analyzed phylogenetic relationships based on 18S and 28S rDNA genes. Host range and specificity of the chytrids was determined by cross-infection assays with host strains, characterized by rbcL and ITS markers. We were able to confirm the identity of two chytrid strains as Endocoenobium eudorinae Ingold and Dangeardia mamillata Schroder and described the third chytrid strain as Algomyces stechlinensis gen. et sp. nov. The three chytrids were assigned to novel and phylogenetically distant clades within the phylum Chytridiomycota, each exhibiting different host specificities. By integrating morphological and molecular data of both the parasitic chytrids and their respective host species, we unveiled cryptic host-parasite associations. This study highlights that a high prevalence of (pseudo)cryptic diversity requires molecular characterization of both phytoplankton host and parasitic chytrid to accurately identify and compare host range and specificity, and to study phytoplankton-chytrid interactions in general.
KW - Chytridiomycota
KW - Dangeardia mamillata
KW - Endocoenobium eudorinae
KW - fungal parasites
KW - life cycle
KW - phytoplankton
Y1 - 2018
U6 - https://doi.org/10.1111/jeu.12632
SN - 1066-5234
SN - 1550-7408
VL - 65
IS - 6
SP - 870
EP - 881
PB - Wiley
CY - Hoboken
ER -
TY - JOUR
A1 - Pereus, D.
A1 - Otieno, J. N.
A1 - Ghorbani, Abdolbaset
A1 - Kocyan, Alexander
A1 - Hilonga, S.
A1 - de Boer, H. J.
T1 - Diversity of Hypoxis species used in ethnomedicine in Tanzania
JF - South African journal of botany : an international interdisciplinary journal for botanical sciences
N2 - The corms of different Hypoxis species (Hypoxidaceae) are used for the treatment and management of a variety of human ailments and disorders in African traditional medicine. However, the used corms are morphologically similar and it is not known whether this has resulted in different species being harvested, prescribed and sold as the same species. Ethnomedicinal information regarding its use in Tanzania is scanty and the available ethnobotanical information about the plants is mostly from various studies done outside Tanzania. The objective of the study was to document the diverse uses of Hypoxis in Tanzania and study what species are used and whether preferences exist for specific species. Focus group discussions and in depth interviews with informants were done in 15 regions of Tanzania to document local uses of Hypoxis species and collect vouchers for identification. Traditional practitioners use Hypoxis to manage a variety of human illness in Tanzania, and appear to use different species indiscriminately for medicine, socio-cultural applications and for food. Medicinal uses include treatment of benign prostate hypertrophy, cancer, diabetes, gout, headache, HIV/AIDS, infertility, ringworms, stomachache, and urinary tract infections. In Tanzania, different Hypoxis species are used indiscriminately for a range of sociocultural and medicinal purposes. The reported medicinal uses could aid testing and evaluation of traditional herbal medicine and more research is needed to test their pharmacological effects. (C) 2018 SAAB. Published by Elsevier B.V. All rights reserved.
KW - Corms
KW - Ethnobotany
KW - Hypoxis
KW - Tanzania
KW - Traditional medicine
Y1 - 2018
U6 - https://doi.org/10.1016/j.sajb.2018.03.004
SN - 0254-6299
SN - 1727-9321
VL - 122
SP - 336
EP - 341
PB - Elsevier
CY - Amsterdam
ER -
TY - JOUR
A1 - Reverey, Florian
A1 - Ganzert, Lars
A1 - Lischeid, Gunnar
A1 - Ulrich, Andreas
A1 - Premke, Katrin
A1 - Grossart, Hans-Peter
T1 - Dry-wet cycles of kettle hole sediments leave a microbial and biogeochemical legacy
JF - The science of the total environment : an international journal for scientific research into the environment and its relationship with man
N2 - Understanding interrelations between an environment's hydrological past and its current biogeochemistry is necessary for the assessment of biogeochemical and microbial responses to changing hydrological conditions. The question how previous dry-wet events determine the contemporary microbial and biogeochemical state is addressed in this study. Therefore, sediments exposed to the atmosphere of areas with a different hydrological past within one kettle hole, i.e. (1) the predominantly inundated pond center, (2) the pond margin frequently desiccated for longer periods and (3) an intermediate zone, were incubated with the same rewetting treatment. Physicochemical and textural characteristics were related to structural microbial parameters regarding carbon and nitrogen turnover, i.e. abundance of bacteria and fungi, denitrifiers (targeted by the nirK und nirS functional genes) and nitrate ammonifiers (targeted by the nrfA functional gene). Our study reveals that, in combination with varying sediment texture, the hydrological history creates distinct microbial habitats with defined boundary conditions within the kettle hole, mainly driven by redox conditions, pH and organic matter (OM) composition. OM mineralization, as indicated by CO2-outgassing, was most efficient in exposed sediments with a less stable hydrological past. The potential for nitrogen retention via nitrate ammonification was highest in the hydrologically rather stable pond center, counteracting nitrogen loss due to denitrification. Therefore, the degree of hydrological stability is an important factor leaving a microbial and biogeochemical legacy, which determines carbon and nitrogen losses from small lentic freshwater systems in the long term run.
KW - Desiccation
KW - DNRA
KW - Denitrifiers
KW - Organic matter mineralization
KW - Carbon
KW - Nitrogen
Y1 - 2018
U6 - https://doi.org/10.1016/j.scitotenv.2018.01.220
SN - 0048-9697
SN - 1879-1026
VL - 627
SP - 985
EP - 996
PB - Elsevier
CY - Amsterdam
ER -
TY - JOUR
A1 - Malinova, Irina
A1 - Mahto, Harendra
A1 - Brandt, Felix
A1 - AL-Rawi, Shadha
A1 - Qasim, Hadeel
A1 - Brust, Henrike
A1 - Hejazi, Mahdi
A1 - Fettke, Jörg
T1 - EARLY STARVATION1 specifically affects the phosphorylation action of starch-related dikinases
JF - The plant journal
N2 - Starch phosphorylation by starch-related dikinases glucan, water dikinase (GWD) and phosphoglucan, water dikinase (PWD) is a key step in starch degradation. Little information is known about the precise structure of the glucan substrate utilized by the dikinases and about the mechanisms by which these structures may be influenced. A 50-kDa starch-binding protein named EARLY STARVATION1 (ESV1) was analyzed regarding its impact on starch phosphorylation. In various invitro assays, the influences of the recombinant protein ESV1 on the actions of GWD and PWD on the surfaces of native starch granules were analyzed. In addition, we included starches from various sources as well as truncated forms of GWD. ESV1 preferentially binds to highly ordered, -glucans, such as starch and crystalline maltodextrins. Furthermore, ESV1 specifically influences the action of GWD and PWD at the starch granule surface. Starch phosphorylation by GWD is decreased in the presence of ESV1, whereas the action of PWD increases in the presence of ESV1. The unique alterations observed in starch phosphorylation by the two dikinases are discussed in regard to altered glucan structures at the starch granule surface.
KW - Arabidopsis thaliana
KW - EARLY STARVATION1
KW - glucan
KW - phosphoglucan
KW - starch granule surface
KW - starch phosphorylation
KW - water dikinase
Y1 - 2018
U6 - https://doi.org/10.1111/tpj.13937
SN - 0960-7412
SN - 1365-313X
VL - 95
IS - 1
SP - 126
EP - 137
PB - Wiley
CY - Hoboken
ER -
TY - JOUR
A1 - Odongo, Grace Akinyi
A1 - Schlotz, Nina
A1 - Baldermann, Susanne
A1 - Neugart, Susanne
A1 - Ngwene, Benard
A1 - Schreiner, Monika
A1 - Lamy, Evelyn
T1 - Effects of Amaranthus cruentus L. on aflatoxin B1- and oxidative stress-induced DNA damage in human liver (HepG2) cells
JF - Food bioscience
N2 - Amaranth is presently an underutilized crop despite its high content of micronutrients/bioactive phytochemicals and its capacity to thrive in harsh environmental condition. The present study aimed at determining the health benefits of Amaranthus cruentus L. in terms of protection against DNA damage induced by the mycotoxin aflatoxin B1 (AFB1) and oxidative stress using comet assay. The antioxidant potential was further investigated using electron paramagnetic resonance spectroscopy (EPR) and an ARE/Nrf2 reporter gene assay in vitro in a human liver model using the HepG2 cell line. Ethanolic extracts from fresh leaves grown under controlled conditions were used and additionally analyzed for their phytochemical content using liquid chromatography-mass spectrometry (LC-MS). The extracts inhibited both AFB1- and oxidative stress-induced DNA damage in a concentration dependent way with a maximum effect of 57% and 81%, respectively. Oxidative stress triggered using ferrous sulfate was blocked by up to 38% (EPR); the potential to induce antioxidant enzymes using ARE/Nrf2-mediated gene expression was also confirmed. Based on these in vitro findings, further studies on the health-protecting effects of A. cruentus are encouraged to fully explore its health promoting potential and provide the scientific basis for encouraging its cultivation and consumption.
KW - African indigenous vegetables
KW - Aflatoxin B1
KW - Amaranthaceae
KW - Amaranth
KW - Aspergillus
KW - Cancer prevention
Y1 - 2018
U6 - https://doi.org/10.1016/j.fbio.2018.09.006
SN - 2212-4292
SN - 2212-4306
VL - 26
SP - 42
EP - 48
PB - Elsevier
CY - Amsterdam
ER -
TY - JOUR
A1 - Müller, Sandra Marie
A1 - Ebert, Franziska
A1 - Raber, Georg
A1 - Meyer, Sören
A1 - Bornhorst, Julia
A1 - Hüwel, Stephan
A1 - Galla, Hans-Joachim
A1 - Francesconi, Kevin A.
A1 - Schwerdtle, Tanja
T1 - Effects of arsenolipids on in vitro blood-brain barrier model
JF - Archives of toxicology : official journal of EUROTOX
N2 - Arsenic-containing hydrocarbons (AsHCs), a subgroup of arsenolipids (AsLs) occurring in fish and edible algae, possess a substantial neurotoxic potential in fully differentiated human brain cells. Previous in vivo studies indicating that AsHCs cross the blood–brain barrier of the fruit fly Drosophila melanogaster raised the question whether AsLs could also cross the vertebrate blood–brain barrier (BBB). In the present study, we investigated the impact of several representatives of AsLs (AsHC 332, AsHC 360, AsHC 444, and two arsenic-containing fatty acids, AsFA 362 and AsFA 388) as well as of their metabolites (thio/oxo-dimethylpropionic acid, dimethylarsinic acid) on porcine brain capillary endothelial cells (PBCECs, in vitro model for the blood–brain barrier). AsHCs exerted the strongest cytotoxic effects of all investigated arsenicals as they were up to fivefold more potent than the toxic reference species arsenite (iAsIII). In our in vitro BBB-model, we observed a slight transfer of AsHC 332 across the BBB after 6 h at concentrations that do not affect the barrier integrity. Furthermore, incubation with AsHCs for 72 h led to a disruption of the barrier at sub-cytotoxic concentrations. The subsequent immunocytochemical staining of three tight junction proteins revealed a significant impact on the cell membrane. Because AsHCs enhance the permeability of the in vitro blood–brain barrier, a similar behavior in an in vivo system cannot be excluded. Consequently, AsHCs might facilitate the transfer of accompanying foodborne toxicants into the brain.
KW - Arsenolipids
KW - Arsenic-containing hydrocarbons
KW - Arsenic-containing fatty acids
KW - In vitro blood-brain barrier model
Y1 - 2017
SN - 0340-5761
SN - 1432-0738
VL - 92
IS - 2
SP - 823
EP - 832
PB - Springer
CY - Heidelberg
ER -
TY - JOUR
A1 - Laux, Eva-Maria
A1 - Bier, Frank Fabian
A1 - Hölzel, Ralph
T1 - Electrode-based AC electrokinetics of proteins
BT - a mini-review
JF - Bioelectrochemistry : official journal of the Bioelectrochemical Society ; an international journal devoted to electrochemical aspects of biology and biological aspects of electrochemistry
N2 - Employing electric phenomena for the spatial manipulation of bioparticles from whole cells down to dissolved molecules has become a useful tool in biotechnology and analytics. AC electrokinetic effects like dielectrophoresis and AC electroosmosis are increasingly used to concentrate, separate and immobilize DNA and proteins. With the advance of photolithographical micro- and nanofabrication methods, novel or improved bioanalytical applications benefit from concentrating analytes, signal enhancement and locally controlled immobilization by AC electrokinetic effects. In this review of AC electrokinetics of proteins, the respective studies are classified according to their different electrode geometries: individual electrode pairs, interdigitated electrodes, quadrupole electrodes, and 3D configurations of electrode arrays. Known advantages and disadvantages of each layout are discussed.
KW - AC electrokinetics
KW - Dielectrophoresis
KW - Electrodes
KW - Electroosmosis
KW - Proteins
Y1 - 2017
U6 - https://doi.org/10.1016/j.bioelechem.2017.11.010
SN - 1567-5394
SN - 1878-562X
VL - 120
SP - 76
EP - 82
PB - Elsevier B.V.
CY - Amsterdam
ER -
TY - JOUR
A1 - Zhang, Xiaorong
A1 - Yarman, Aysu
A1 - Erdossy, Julia
A1 - Katz, Sagie
A1 - Zebger, Ingo
A1 - Jetzschmann, Katharina J.
A1 - Altintas, Zeynep
A1 - Wollenberger, Ulla
A1 - Gyurcsanyi, Robert E.
A1 - Scheller, Frieder W.
T1 - Electrosynthesized MIPs for transferrin
BT - Plastibodies or nano-filters?
JF - Biosensors and bioelectronics : the principal international journal devoted to research, design development and application of biosensors and bioelectronics
N2 - Molecularly imprinted polymer (MP) nanofilrns for transferrin (Trf) have been synthesized on gold surfaces by electro-polymerizing the functional monomer scopoletin in the presence of the protein target or around pre-adsorbed Trf. As determined by atomic force microscopy (AFM) the film thickness was comparable with the molecular dimension of the target. The target (re)binding properties of the electro-synthesized MIP films was evaluated by cyclic voltammetry (CV) and square wave voltammetry (SWV) through the target-binding induced permeability changes of the MIP nanofilms to the ferricyanide redox marker, as well as by surface plasmon resonance (SPR) and surface enhanced infrared absorption spectroscopy (SEIRAS) of the immobilized protein molecules. For Trf a linear concentration dependence in the lower micromolar range and an imprinting factor of similar to 5 was obtained by SWV and SPR. Furthermore, non-target proteins including the iron-free apo-Trf were discriminated by pronounced size and shape specificity. Whilst it is generally assumed that the rebinding of the target or of cross-reacting proteins exclusively takes place at the polymer here we considered also the interaction of the protein molecules with the underlying gold transducers. We demonstrate by SWV that adsorption of proteins suppresses the signal of the redox marker even at the bare gold surface and by SEIRAS that the treatment of the MIP with proteinase K or NaOH only partially removes the target protein. Therefore, we conclude that when interpreting binding of proteins to directly MIP-covered gold electrodes the interactions between the protein and the gold surface should also be considered.
KW - Molecularly imprinted polymer
KW - Scopoletin
KW - Transferrin
KW - Protein adsorption
KW - Redox marker
Y1 - 2018
U6 - https://doi.org/10.1016/j.bios.2018.01.011
SN - 0956-5663
SN - 1873-4235
VL - 105
SP - 29
EP - 35
PB - Elsevier
CY - Oxford
ER -
TY - JOUR
A1 - Yarman, Aysu
T1 - Electrosynthesized Molecularly Imprinted Polymer for Laccase Using the Inactivated Enzyme as the Target
JF - Bulletin of the Korean chemical society
N2 - The first molecularly imprinted polymer (MIP) for the recognition of the copper-enzyme laccase was successfully prepared by electropolymerizing scopoletin in the presence of alkaline-inactivated enzyme. Laccase-MIP and the control polymer without laccase (nonimprinted polymer, NIP) were characterized by voltammetry using the redox marker ferricyanide. After electropolymerization, the signals for ferricyanide for both the MIP and the NIP were almost completely suppressed and increased after removal of the target from the polymer layer. Rebinding of both inactivated and active laccase decreased the ferricyanide peak currents to almost equal extent. The relative decrease of signal suppression approached saturation above 10 nM. Furthermore, the surface activity of rebound laccase toward the oxidation of catechol was investigated. The surface activity approached saturation above 10 nM, a value close to the value of the measurements with ferricyanide. Interaction of NIP with laccase brought about a six times smaller signal of catechol oxidation.
KW - Molecularly imprinted polymers
KW - Biomimetic sensors
KW - Laccase
KW - Electropolymerization
KW - Scopoletin
Y1 - 2018
U6 - https://doi.org/10.1002/bkcs.11413
SN - 1229-5949
VL - 39
IS - 4
SP - 483
EP - 488
PB - Wiley-VCH
CY - Weinheim
ER -
TY - JOUR
A1 - Krüger-Genge, Anne
A1 - Dietze, Stefanie
A1 - Yan, Wan
A1 - Liu, Yue
A1 - Fang, Liang
A1 - Kratz, Karl
A1 - Lendlein, Andreas
A1 - Jung, Friedrich
T1 - Endothelial cell migration, adhesion and proliferation on different polymeric substrates
JF - Clinical hemorheology and microcirculation : blood flow and vessels
N2 - BACKGROUND: The formation of a functionally-confluent endothelial cell (EC) monolayer affords proliferation of EC, which only happens in case of appropriate migratory activity. AIM OF THE STUDY: The migratory pathway of human umbilical endothelial cells (HUVEC) was investigated on different polymeric substrates. MATERIAL AND METHODS: Surface characterization of the polymers was performed by contact angle measurements and atomic force microscopy under wet conditions. 30,000 HUVEC per well were seeded on polytetrafluoroethylene (PTFE) (theta(adv) = 119 degrees +/- 2 degrees), on low-attachment plate LAP (theta(adv) = 28 degrees +/- 2 degrees) and on polystyrene based tissue culture plates (TCP, theta(adv) = 22 degrees +/- 1 degrees). HUVEC tracks (trajectories) were recorded by time lapse microscopy and the euclidean distance (straight line between starting and end point), the total distance and the velocities of HUVEC not leaving the vision field were determined. RESULTS: On PTFE, 42 HUVEC were in the vision field directly after seeding. The mean length of single migration steps (SML) was 6.1 +/- 5.2 mu m, the mean velocity (MV) 0.40 +/- 0.3 mu m.min(-1) and the complete length of the trajectory (LT) was 710 +/- 440 mu m. On TCP 82 HUVEC were in the vision field subsequent to seeding. The LT was 840 +/- 550 mu m, the SML 6.1 +/- 5.2 mu m and the MV 0.44 +/- 0.3 mu m.min(-1). The trajectories on LAP differed significantly in respect to SML (2.4 +/- 3.9 mu m, p <0.05), the MV (0.16 +/- 0.3 mu m.min(-1), p <0.05) and the LT (410 +/- 300 mu m, p <0.05), compared to PTFE and TCP. Solely on TCP a nearly confluent EC monolayer developed after three days. While on TCP diffuse signals of vinculin were found over the whole basal cell surface organizing the binding of the cells by focal adhesions, on PTFE vinculin was merely arranged at the cell rims, and on the hydrophilic material (LAP) no focal adhesions were found. CONCLUSION: The study revealed that the wettability of polymers affected not only the initial adherence but also the migration of EC, which is of importance for the proliferation and ultimately the endothelialization of polymer-based biomaterials.
KW - Endothelial cells
KW - migration
KW - polymer-based biomaterials
KW - cytokine release
Y1 - 2019
U6 - https://doi.org/10.3233/CH-189317
SN - 1386-0291
SN - 1875-8622
VL - 70
IS - 4
SP - 511
EP - 529
PB - IOS Press
CY - Amsterdam
ER -
TY - THES
A1 - Agrawal, Shreya
T1 - Engineering the isoprenoid pathway for molecular farming and effect of tRNA(Glu) manipulation on tetrapyrrole biosynthesis
Y1 - 2018
ER -
TY - JOUR
A1 - Neumann, Bettina
A1 - Götz, Robert
A1 - Wrzolek, Pierre
A1 - Scheller, Frieder W.
A1 - Weidinger, Inez M.
A1 - Schwalbe, Matthias
A1 - Wollenberger, Ulla
T1 - Enhancement of the Electrocatalytic Activity of Thienyl-Substituted Iron Porphyrin Electropolymers by a Hangman Effect
JF - ChemCatChem : heterogeneous & homogeneous & bio- & nano-catalysis ; a journal of ChemPubSoc Europe
N2 - The thiophene-modified iron porphyrin FeT3ThP and the respective iron Hangman porphyrin FeH3ThP, incorporating a carboxylic acid hanging group in the second coordination sphere of the iron center, were electropolymerized on glassy carbon electrodes using 3,4-ethylenedioxythiophene (EDOT) as co-monomer. Scanning electron microscopy images and Resonance Raman spectra demonstrated incorporation of the porphyrin monomers into a fibrous polymer network. Porphyrin/polyEDOT films catalyzed the reduction of molecular oxygen in a four-electron reaction to water with onset potentials as high as +0.14V vs. Ag/AgCl in an aqueous solution of pH7. Further, FeT3ThP/polyEDOT films showed electrocatalytic activity towards reduction of hydrogen peroxide at highly positive potentials, which was significantly enhanced by introduction of the carboxylic acid hanging group in FeH3ThP. The second coordination sphere residue promotes formation of a highly oxidizing reaction intermediate, presumably via advantageous proton supply, as observed for peroxidases and catalases making FeH3ThP/polyEDOT films efficient mimics of heme enzymes.
KW - activation of oxygen species
KW - electro-polymerization
KW - Hangman porphyrin
KW - heterogeneous catalysis
KW - immobilization
Y1 - 2018
U6 - https://doi.org/10.1002/cctc.201800934
SN - 1867-3880
SN - 1867-3899
VL - 10
IS - 19
SP - 4353
EP - 4361
PB - Wiley-VCH
CY - Weinheim
ER -
TY - JOUR
A1 - Weyrich, Alexandra
A1 - Lenz, Dorina
A1 - Fickel, Jörns
T1 - Environmental Change-Dependent Inherited Epigenetic Response
JF - GENES
N2 - Epigenetic modifications are a mechanism conveying environmental information to subsequent generations via parental germ lines. Research on epigenetic responses to environmental changes in wild mammals has been widely neglected, as well as studies that compare responses to changes in different environmental factors. Here, we focused on the transmission of DNA methylation changes to naive male offspring after paternal exposure to either diet (~40% less protein) or temperature increase (10 °C increased temperature). Because both experiments focused on the liver as the main metabolic and thermoregulation organ, we were able to decipher if epigenetic changes differed in response to different environmental changes. Reduced representation bisulfite sequencing (RRBS) revealed differentially methylated regions (DMRs) in annotated genomic regions in sons sired before (control) and after the fathers’ treatments. We detected both a highly specific epigenetic response dependent on the environmental factor that had changed that was reflected in genes involved in specific metabolic pathways, and a more general response to changes in outer stimuli reflected by epigenetic modifications in a small subset of genes shared between both responses. Our results indicated that fathers prepared their offspring for specific environmental changes by paternally inherited epigenetic modifications, suggesting a strong paternal contribution to adaptive processes.
KW - DNA methylation
KW - exposure
KW - wild mammal species
KW - inheritance
KW - plasticity
KW - adaptation
KW - RRBS
Y1 - 2018
U6 - https://doi.org/10.3390/genes10010004
SN - 2073-4425
VL - 10
IS - 1
PB - MDPI
CY - Basel
ER -
TY - JOUR
A1 - Grzesiuk, Malgorzata
A1 - Spijkerman, Elly
A1 - Lachmann, Sabrina C.
A1 - Wacker, Alexander
T1 - Environmental concentrations of pharmaceuticals directly affect phytoplankton and effects propagate through trophic interactions
JF - Ecotoxicology and Environmental Safety
N2 - Pharmaceuticals are found in freshwater ecosystems where even low concentrations in the range of ng L−1 may affect aquatic organisms. In the current study, we investigated the effects of chronic exposure to three pharmaceuticals on two microalgae, a potential modulation of the effects by additional inorganic phosphorus (Pi) limitation, and a potential propagation of the pharmaceuticals’ effect across a trophic interaction. The latter considers that pharmaceuticals are bioaccumulated by algae, potentially metabolized into more (or less) toxic derivates and consequently consumed by zooplankton. We cultured Acutodesmus obliquus and Nannochloropsis limnetica in Pi-replete and Pi-limited medium contaminated with one of three commonly human used pharmaceuticals: fluoxetine, ibuprofen, and propranolol. Secondly, we tested to what extent first level consumers (Daphnia magna) were affected when fed with pharmaceutical-grown algae. Chronic exposure, covering 30 generations, led to (i) decreased cell numbers of A. obliquus in the presence of fluoxetine (under Pi-replete conditions) (ii) increased carotenoid to chlorophyll ratios in N. limnetica (under Pi-limited conditions), and (iii) increased photosynthetic yields in A. obliquus (in both Pi-conditions). In addition, ibuprofen affected both algae and their consumer: Feeding ibuprofen-contaminated algae to Pi-stressed D. magna improved their survival. We demonstrate, that even very low concentrations of pharmaceuticals present in freshwater ecosystems can significantly affect aquatic organisms when chronically exposed. Our study indicates that pharmaceutical effects can cross trophic levels and travel up the food chain.
KW - Freshwater microalgae
KW - Cellular phosphorus
KW - Daphnia
KW - Human used-drugs
KW - Chronic exposure
KW - Environmental risk
KW - Fatty acids
Y1 - 2018
U6 - https://doi.org/10.1016/j.ecoenv.2018.03.019
SN - 0147-6513
SN - 1090-2414
VL - 156
SP - 271
EP - 278
PB - Elsevier
CY - San Diego
ER -
TY - JOUR
A1 - Fabian, Jenny
A1 - Zlatanovic, Sanja
A1 - Mutz, Michael
A1 - Grossart, Hans-Peter
A1 - van Geldern, Robert
A1 - Ulrich, Andreas
A1 - Gleixner, Gerd
A1 - Premke, Katrin
T1 - Environmental control on microbial turnover of leaf carbon in streams
BT - Ecological function of phototrophic-heterotrophic interactions
JF - Frontiers in microbiology
N2 - In aquatic ecosystems, light availability can significantly influence microbial turnover of terrestrial organic matter through associated metabolic interactions between phototrophic and heterotrophic communities. However, particularly in streams, microbial functions vary significantly with the structure of the streambed, that is the distribution and spatial arrangement of sediment grains in the streambed. It is therefore essential to elucidate how environmental factors synergistically define the microbial turnover of terrestrial organic matter in order to better understand the ecological role of photoheterotrophic interactions in stream ecosystem processes. In outdoor experimental streams, we examined how the structure of streambeds modifies the influence of light availability on microbial turnover of leaf carbon (C). Furthermore, we investigated whether the studied relationships of microbial leaf C turnover to environmental conditions are affected by flow intermittency commonly occurring in streams. We applied leaves enriched with a C-13-stable isotope tracer and combined quantitative and isotope analyses. We thereby elucidated whether treatment induced changes in C turnover were associated with altered use of leaf C within the microbial food web. Moreover, isotope analyses were combined with measurements of microbial community composition to determine whether changes in community function were associated with a change in community composition. In this study, we present evidence, that environmental factors interactively determine how phototrophs and heterotrophs contribute to leaf C turnover. Light availability promoted the utilization of leaf C within the microbial food web, which was likely associated with a promoted availability of highly bioavailable metabolites of phototrophic origin. However, our results additionally confirm that the structure of the streambed modifies light-related changes in microbial C turnover. From our observations, we conclude that the streambed structure influences the strength of photo-heterotrophic interactions by defining the spatial availability of algal metabolites in the streambed and the composition of microbial communities. Collectively, our multifactorial approach provides valuable insights into environmental controls on the functioning of stream ecosystems.
KW - algae
KW - bacteria
KW - microbial interactions
KW - C-13 stable isotopes
KW - PLFA
KW - terrestrial carbon
KW - streambed structure
KW - light
Y1 - 2018
U6 - https://doi.org/10.3389/fmicb.2018.01044
SN - 1664-302X
VL - 9
PB - Frontiers Research Foundation
CY - Lausanne
ER -
TY - JOUR
A1 - Bálint, Miklós
A1 - Pfenninger, Markus
A1 - Grossart, Hans-Peter
A1 - Taberlet, Pierre
A1 - Vellend, Mark
A1 - Leibold, Mathew A.
A1 - Englund, Goran
A1 - Bowler, Diana
T1 - Environmental DNA time series in ecology
JF - Trends in ecology & evolution
N2 - Ecological communities change in time and space, but long-term dynamics at the century-to-millennia scale are poorly documented due to lack of relevant data sets. Nevertheless, understanding long-term dynamics is important for explaining present-day biodiversity patterns and placing conservation goals in a historical context. Here, we use recent examples and new perspectives to highlight how environmental DNA (eDNA) is starting to provide a powerful new source of temporal data for research questions that have so far been overlooked, by helping to resolve the ecological dynamics of populations, communities, and ecosystems over hundreds to thousands of years. We give examples of hypotheses that may be addressed by temporal eDNA biodiversity data, discuss possible research directions, and outline related challenges.
Y1 - 2018
U6 - https://doi.org/10.1016/j.tree.2018.09.003
SN - 0169-5347
SN - 1872-8383
VL - 33
IS - 12
SP - 945
EP - 957
PB - Elsevier
CY - London
ER -
TY - JOUR
A1 - Bachmann, Jennifer
A1 - Heimbach, Tabea
A1 - Hassenrück, Christiane
A1 - Kopprio, German A.
A1 - Iversen, Morten Hvitfeldt
A1 - Grossart, Hans-Peter
A1 - Gärdes, Astrid
T1 - Environmental Drivers of Free-Living vs. Particle-Attached Bacterial Community Composition in the Mauritania Upwelling System
JF - Frontiers in microbiology
N2 - Saharan dust input and seasonal upwelling along North-West Africa provide a model system for studying microbial processes related to the export and recycling of nutrients. This study offers the first molecular characterization of prokaryotic particle-attached (PA; > 3.0 mu m) and free-living (FL; 0.2-3.0 mu m) players in this important ecosystem during August 2016. Environmental drivers for alpha-diversity, bacterial community composition, and differences between FL and PA fractions were identified. The ultra-oligotrophic waters off Senegal were dominated by Cyanobacteria while higher relative abundances of Alphaproteobacteria, Bacteroidetes, Verrucomicrobia, and Planctomycetes (known particle-degraders) occurred in the upwelling area. Temperature, proxy for different water masses, was the best predictor for changes in FL communities. PA community variation was best explained by temperature and ammonium. Bray Curtis dissimilarities between FL and PA were generally very high and correlated with temperature and salinity in surface waters. Greatest similarities between FL and PA occurred at the deep chlorophyll maximum, where bacterial substrate availability was likely highest. This indicates that environmental drivers do not only influence changes among FL and PA communities but also differences between them. This could provide an explanation for contradicting results obtained by different studies regarding the dissimilarity/similarity between FL and PA communities and their biogeochemical functions.
KW - prokaryotes
KW - biodiversity
KW - microbial ecology
KW - alpha diversity
KW - Bray Curtis dissimilarity
KW - temperature
KW - salinity
KW - 16S rRNA Illumina amplicon sequencing
Y1 - 2018
U6 - https://doi.org/10.3389/fmicb.2018.02836
SN - 1664-302X
VL - 9
PB - Frontiers Research Foundation
CY - Lausanne
ER -
TY - JOUR
A1 - Galbete, Cecilia
A1 - Schwingshackl, Lukas
A1 - Schwedhelm, Carolina
A1 - Boeing, Heiner
A1 - Schulze, Matthias Bernd
T1 - Evaluating Mediterranean diet and risk of chronic disease in cohort studies
BT - an umbrella review of meta-analyses
JF - European journal of epidemiology
N2 - Several meta-analyses have been published summarizing the associations of the Mediterranean diet (MedDiet) with chronic diseases. We evaluated the quality and credibility of evidence from these meta-analyses as well as characterized the different indices used to define MedDiet and re-calculated the associations with the different indices identified. We conducted an umbrella review of meta-analyses on cohort studies evaluating the association of the MedDiet with type 2 diabetes, cardiovascular disease, cancer and cognitive-related diseases. We used the AMSTAR (A MeaSurement Tool to Assess systematic Reviews) checklist to evaluate the methodological quality of the meta-analyses, and the NutriGrade scoring system to evaluate the credibility of evidence. We also identified different indices used to define MedDiet; tests for subgroup differences were performed to compare the associations with the different indices when at least 2 studies were available for different definitions. Fourteen publications were identified and within them 27 meta-analyses which were based on 70 primary studies. Almost all meta-analyses reported inverse associations between MedDiet and risk of chronic disease, but the credibility of evidence was rated low to moderate. Moreover, substantial heterogeneity was observed on the use of the indices assessing adherence to the MedDiet, but two indices were the most used ones [Trichopoulou MedDiet (tMedDiet) and alternative MedDiet (aMedDiet)]. Overall, we observed little difference in risk associations comparing different MedDiet indices in the subgroup meta-analyses. Future prospective cohort studies are advised to use more homogenous definitions of the MedDiet to improve the comparability across meta-analyses.
KW - Mediterranean diet
KW - Chronic diseases
KW - Umbrella review
KW - Meta-analyses
KW - Cohort studies
KW - Heterogeneity
Y1 - 2018
U6 - https://doi.org/10.1007/s10654-018-0427-3
SN - 0393-2990
SN - 1573-7284
VL - 33
IS - 10
SP - 909
EP - 931
PB - Springer
CY - Dordrecht
ER -
TY - JOUR
A1 - Wozniak, Natalia Joanna
A1 - Sicard, Adrien
T1 - Evolvability of flower geometry
BT - Convergence in pollinator-driven morphological evolution of flowers
JF - Seminars in cell & developmental biology
N2 - Flowers represent a key innovation during plant evolution. Driven by reproductive optimization, evolution of flower morphology has been central in boosting species diversification. In most cases, this has happened through specialized interactions with animal pollinators and subsequent reduction of gene flow between specialized morphs. While radiation has led to an enormous variability in flower forms and sizes, recurrent evolutionary patterns can be observed. Here, we discuss the targets of selection involved in major trends of pollinator-driven flower evolution. We review recent findings on their adaptive values, developmental grounds and genetic bases, in an attempt to better understand the repeated nature of pollinator-driven flower evolution. This analysis highlights how structural innovation can provide flexibility in phenotypic evolution, adaptation and speciation. (C) 2017 Elsevier Ltd. All rights reserved.
KW - Flower
KW - Developmental evolution
KW - Morphogenesis
KW - Angiosperms
KW - Co-evolution
KW - Plant-pollinator interactions
Y1 - 2018
U6 - https://doi.org/10.1016/j.semcdb.2017.09.028
SN - 1084-9521
VL - 79
SP - 3
EP - 15
PB - Elsevier
CY - London
ER -
TY - JOUR
A1 - Westbury, Michael V.
A1 - Hartmann, Stefanie
A1 - Barlow, Axel
A1 - Wiesel, Ingrid
A1 - Leo, Viyanna
A1 - Welch, Rebecca
A1 - Parker, Daniel M.
A1 - Sicks, Florian
A1 - Ludwig, Arne
A1 - Dalen, Love
A1 - Hofreiter, Michael
T1 - Extended and continuous decline in effective population size results in low genomic diversity in the world's rarest hyena species, the brown hyena
JF - Molecular biology and evolution
N2 - Hyenas (family Hyaenidae), as the sister group to cats (family Felidae), represent a deeply diverging branch within the cat-like carnivores (Feliformia). With an estimated population size of <10,000 individuals worldwide, the brown hyena (Parahyaena brunnea) represents the rarest of the four extant hyena species and has been listed as Near Threatened by the IUCN. Here, we report a high-coverage genome from a captive bred brown hyena and both mitochondrial and low-coverage nuclear genomes of 14 wild-caught brown hyena individuals from across southern Africa. We find that brown hyena harbor extremely low genetic diversity on both the mitochondrial and nuclear level, most likely resulting from a continuous and ongoing decline in effective population size that started similar to 1 Ma and dramatically accelerated towards the end of the Pleistocene. Despite the strikingly low genetic diversity, we find no evidence of inbreeding within the captive bred individual and reveal phylogeographic structure, suggesting the existence of several potential subpopulations within the species.
KW - evolution
KW - hyena
KW - genomics
KW - population genomics
KW - diversity
Y1 - 2018
U6 - https://doi.org/10.1093/molbev/msy037
SN - 0737-4038
SN - 1537-1719
VL - 35
IS - 5
SP - 1225
EP - 1237
PB - Oxford Univ. Press
CY - Oxford
ER -
TY - JOUR
A1 - Mumm, Rebekka
A1 - Godina, Elena
A1 - Koziel, Slawomir
A1 - Musalek, Martin
A1 - Sedlak, Petr
A1 - Wittwer-Backofen, Ursula
A1 - Hess, Volker
A1 - Dasgupta, Parasmani
A1 - Henneberg, Maciej
A1 - Scheffler, Christiane
T1 - External skeletal robusticity of children and adolescents
BT - European references from birth to adulthood and international comparisons
JF - Journal of biological and clinical anthropology
JF - Anthropologischer Anzeiger ; Mitteilungsorgan der Gesellschaft für Anthropologie
N2 - Background: In our modern world, the way of life in nutritional and activity behaviour has changed. As a consequence, parallel trends of an epidemic of overweight and a decline in external skeletal robusticity are observed in children and adolescents. Aim: We aim to develop reference centiles for external skeletal robusticity of European girls and boys aged 0 to 18 years using the Frame Index as an indicator and identify population specific age-related patterns. Methods: We analysed cross-sectional & longitudinal data on body height and elbow breadth of boys and girls from Europe (0-18 years, n = 41.679), India (7-18 years, n = 3.297) and South Africa (3-18 years, n = 4.346). As an indicator of external skeletal robusticity Frame Index after Frisancho (1990) was used. We developed centiles for boys and girls using the LMS-method and its extension. Results: Boys have greater external skeletal robusticity than girls. Whereas in girls Frame Index decreases continuously during growth, an increase of Frame Index from 12 to 16 years in European boys can be observed. Indian and South African boys are almost similar in Frame Index to European boys. In girls, the pattern is slightly different. Whereas South African girls are similar to European girls, Indian girls show a lesser external skeletal robusticity. Conclusion: Accurate references for external skeletal robusticity are needed to evaluate if skeletal development is adequate per age. They should be used to monitor effects of changes in way of life and physical activity levels in children and adolescents to avoid negative health outcomes like osteoporosis and arthrosis.
Y1 - 2018
U6 - https://doi.org/10.1127/anthranz/2018/0826
SN - 0003-5548
VL - 74
IS - 5
SP - 383
EP - 391
PB - Schweizerbart
CY - Stuttgart
ER -
TY - JOUR
A1 - Bayerl, Helmut
A1 - Kraus, Robert H. S.
A1 - Nowak, Carsten
A1 - Foerster, Daniel W.
A1 - Fickel, Jörns
A1 - Kühn, Ralph
T1 - Fast and cost-effective single nucleotide polymorphism (SNP) detection in the absence of a reference genome using semideep next-generation Random Amplicon Sequencing (RAMseq)
JF - Molecular ecology resources
N2 - Biodiversity has suffered a dramatic global decline during the past decades, and monitoring tools are urgently needed providing data for the development and evaluation of conservation efforts both on a species and on a genetic level. However, in wild species, the assessment of genetic diversity is often hampered by the lack of suitable genetic markers. In this article, we present Random Amplicon Sequencing (RAMseq), a novel approach for fast and cost-effective detection of single nucleotide polymorphisms (SNPs) in nonmodel species by semideep sequencing of random amplicons. By applying RAMseq to the Eurasian otter (Lutra lutra), we identified 238 putative SNPs after quality filtering of all candidate loci and were able to validate 32 of 77 loci tested. In a second step, we evaluated the genotyping performance of these SNP loci in noninvasive samples, one of the most challenging genotyping applications, by comparing it with genotyping results of the same faecal samples at microsatellite markers. We compared (i) polymerase chain reaction (PCR) success rate, (ii) genotyping errors and (iii) Mendelian inheritance (population parameters). SNPs produced a significantly higher PCR success rate (75.5% vs. 65.1%) and lower mean allelic error rate (8.8% vs. 13.3%) than microsatellites, but showed a higher allelic dropout rate (29.7% vs. 19.8%). Genotyping results showed no deviations from Mendelian inheritance in any of the SNP loci. Hence, RAMseq appears to be a valuable tool for the detection of genetic markers in nonmodel species, which is a common challenge in conservation genetic studies.
KW - high-throughput sequencing
KW - Lutra lutra
KW - nonmodel species
KW - RAMseq
KW - RAPD
KW - variant detection
Y1 - 2018
U6 - https://doi.org/10.1111/1755-0998.12717
SN - 1755-098X
SN - 1755-0998
VL - 18
IS - 1
SP - 107
EP - 117
PB - Wiley
CY - Hoboken
ER -
TY - JOUR
A1 - Lu, Yong-Ping
A1 - Reichetzeder, Christoph
A1 - Prehn, Cornelia
A1 - von Websky, Karoline
A1 - Slowinski, Torsten
A1 - Chen, You-Peng
A1 - Yin, Liang-Hong
A1 - Kleuser, Burkhard
A1 - Yang, Xue-Song
A1 - Adamski, Jerzy
A1 - Hocher, Berthold
T1 - Fetal serum metabolites are independently associated with Gestational diabetes mellitus
JF - Cellular physiology and biochemistry : international journal of experimental cellular physiology, biochemistry and pharmacology
N2 - Background/Aims: Gestational diabetes (GDM) might be associated with alterations in the metabolomic profile of affected mothers and their offspring. Until now, there is a paucity of studies that investigated both, the maternal and the fetal serum metabolome in the setting of GDM. Mounting evidence suggests that the fetus is not just passively affected by gestational disease but might play an active role in it. Metabolomic studies performed in maternal blood and fetal cord blood could help to better discern distinct fetal from maternal disease interactions. Methods: At the time of birth, serum samples from mothers and newborns (cord blood samples) were collected and screened for 163 metabolites utilizing tandem mass spectrometry. The cohort consisted of 412 mother/child pairs, including 31 cases of maternal GDM. Results: An initial non-adjusted analysis showed that eight metabolites in the maternal blood and 54 metabolites in the cord blood were associated with GDM. After Benjamini-Hochberg (BH) procedure and adjustment for confounding factors for GDM, fetal phosphatidylcholine acyl-alkyl C 32:1 and proline still showed an independent association with GDM. Conclusions: This study found metabolites in cord blood which were associated with GDM, even after adjustment for established risk factors of GDM. To the best of our knowledge, this is the first study demonstrating an independent association between fetal serum metabolites and maternal GDM. Our findings might suggest a potential effect of the fetal metabolome on maternal GDM. (c) 2018 The Author(s) Published by S. Karger AG, Basel
KW - Gestational diabetes
KW - Metabolomics
KW - Phosphatidylcholine acyl-alkyl C 32:1
KW - Proline
Y1 - 2018
U6 - https://doi.org/10.1159/000487119
SN - 1015-8987
SN - 1421-9778
VL - 45
IS - 2
SP - 625
EP - 638
PB - Karger
CY - Basel
ER -
TY - JOUR
A1 - Reckendorf, Anja
A1 - Ludes-Wehrmeister, Eva
A1 - Wohlsein, Peter
A1 - Tiedemann, Ralph
A1 - Siebert, U.
A1 - Lehnert, Kristina
T1 - First record of Halocercus sp (Pseudaliidae) lungworm infections in two stranded neonatal orcas (Orcinus orca)
JF - Parasitology
N2 - Orca (Orcinus orca) strandings are rare and post-mortem examinations on fresh individuals are scarce. Thus, little is known about their parasitological fauna, prevalence of infections, associated pathology and the impact on their health. During post-mortem examinations of two male neonatal orcas stranded in Germany and Norway, lungworm infections were found within the bronchi of both individuals. The nematodes were identified as Halocercus sp. (Pseudaliidae), which have been described in the respiratory tract of multiple odontocete species, but not yet in orcas. The life cycle and transmission pathways of some pseudaliid nematodes are incompletely understood. Lungworm infections in neonatal cetaceans are an unusual finding and thus seem to be an indicator for direct mother-to-calf transmission (transplacental or transmammary) of Halocercus sp. nematodes in orcas.
KW - Cetaceans
KW - endoparasites
KW - killer whale
KW - life cycle
KW - nematodes
KW - vertical transmission
Y1 - 2018
U6 - https://doi.org/10.1017/S0031182018000586
SN - 0031-1820
SN - 1469-8161
VL - 145
IS - 12
SP - 1553
EP - 1557
PB - Cambridge Univ. Press
CY - New York
ER -
TY - JOUR
A1 - Navarro-Retamal, Carlos
A1 - Bremer, Anne
A1 - Ingolfsson, Helgi I.
A1 - Alzate-Morales, Jans
A1 - Caballero, Julio
A1 - Thalhammer, Anja
A1 - Gonzalez, Wendy
A1 - Hincha, Dirk K.
T1 - Folding and Lipid Composition Determine Membrane Interaction of the Disordered Protein COR15A
JF - Biophysical journal
N2 - Plants from temperate climates, such as the model plant Arabidopsis thaliana, are challenged with seasonal low temperatures that lead to increased freezing tolerance in fall in a process termed cold acclimation. Among other adaptations, this involves the accumulation of cold-regulated (COR) proteins, such as the intrinsically disordered chloroplast-localized protein COR15A. Together with its close homolog COR15B, it stabilizes chloroplast membranes during freezing. COR15A folds into amphipathic alpha-helices in the presence of high concentrations of low-molecular-mass crowders or upon dehydration. Under these conditions, the (partially) folded protein binds peripherally to membranes. In our study, we have used coarse-grained molecular dynamics simulations to elucidate the details of COR15A-membrane binding and its effects on membrane structure and dynamics. Simulation results indicate that at least partial folding of COR15A and the presence of highly unsaturated galactolipids in the membranes are necessary for efficient membrane binding. The bound protein is stabilized on the membrane by interactions of charged and polar amino acids with galactolipid headgroups and by interactions of hydrophobic amino acids with the upper part of the fatty acyl chains. Experimentally, the presence of liposomes made from a mixture of lipids mimicking chloroplast membranes induces additional folding in COR15A under conditions of partial dehydration, in agreement with the simulation results.
Y1 - 2018
U6 - https://doi.org/10.1016/j.bpj.2018.08.014
SN - 0006-3495
SN - 1542-0086
VL - 115
IS - 6
SP - 968
EP - 980
PB - Cell Press
CY - Cambridge
ER -
TY - JOUR
A1 - Nitsch, Paula
A1 - Kaupenjohann, Martin
A1 - Wulf, Monika
T1 - Forest continuity, soil depth and tree species are important parameters for SOC stocks in an old forest (Templiner Buchheide, northeast Germany)
JF - Geoderma : an international journal of soil science
N2 - Forest mineral soils have the potential to accumulate large amounts of carbon (C). Numerous factors, which have often been insufficiently studied, affect soil organic C (SOC) stocks. Detailed knowledge of variation in SOC storage is important to assess the C accumulation potential of forest soils. To examine the impacts of forest continuity, soil depth and tree species on SOC stocks, 15 ancient ( > 230 years of forest continuity) and 15 old ( > 100 but < 200 years of forest continuity) forest soils, topsoil and subsoil in the Templiner Buchheide (Brandenburg, NE Germany) were compared. The old forest sites were afforested on former grassland or wasteland. On all sites grew one of three dominant tree species: European beech (Fagus sylvatica), Scots pine (Pinus sylvestris) or oak (Quercus spec.). Pine forest sites had been underplanted with beech and were mixed-species stands. Soil samples were taken down to a mean depth of 55 cm. Total contents of SOC, nitrogen (N), phosphorus (P), sulphur (S), calcium (Ca), potassium (K) and magnesium (Mg); soil pH; and bulk densities were determined. The soils of ancient forest sites stored significantly more total SOC, N, P, S, K and Mg than did the old ones. Mean total SOC stocks in ancient forests of all three tree species were 12-17% larger compared with those in old forests. Significant differences in SOC stocks between the two forest continuity groups appeared only in subsoil and not in topsoil. Pine forest stored larger SOC stocks than did beech and oak forests. Significant differences were found between ancient pine and oak forests and between ancient beech and oak forests. Soils in ancient beech and pine forests at depths of between 29 and 55 cm contained, on average, even 50% larger SOC stocks than did soils at the same depths in ancient oak forests and in all old forests. Forest continuity significantly affected SOC stocks. These results support previous studies that old forests are still able to enrich SOC. Although soil samples were carried out to a mean depth of only 55 cm, the results indicate that differences in SOC stocks between ancient and old forest could also be found in deeper soil layers. It was suggested that beech and mixed-species stands of beech and pine and total soil P stocks had a positive effect on SOC stocks in subsoil. To understand SOC accumulation in forests, especially in subsoil, with a forest continuity of > 100 years, the role of different tree species and of total P cycling in forests, deeper sampling depths and repeated sampling would be required.
KW - Ancient forest
KW - C sequestration
KW - Land-use history
KW - Forest age
KW - Total P
KW - Subsoil
Y1 - 2017
U6 - https://doi.org/10.1016/j.geoderma.2017.08.041
SN - 0016-7061
SN - 1872-6259
VL - 310
SP - 65
EP - 76
PB - Elsevier Science
CY - Amsterdam
ER -
TY - THES
A1 - Hilgers, Leon
T1 - From innovation to diversification
BT - the genetic basis of the molluscan radula and its adaptive diversification in Tylomelania
Y1 - 2018
ER -
TY - JOUR
A1 - Kaufmann, Paul
A1 - Duffus, Benjamin R.
A1 - Teutloff, Christian
A1 - Leimkühler, Silke
T1 - Functional Studies on Oligotropha carboxidovorans Molybdenum-Copper CO Dehydrogenase Produced in Escherichia coli
JF - Biochemistry
N2 - The Mo/Cu-dependent CO dehydrogenase (CODH) from Oligotropha carboxidovorans is an enzyme that is able to catalyze both the oxidation of CO to CO2 and the oxidation of H-2 to protons and electrons. Despite the close to atomic resolution structure (1.1 angstrom), significant uncertainties have remained with regard to the reaction mechanism of substrate oxidation at the unique Mo/Cu center, as well as the nature of intermediates formed during the catalytic cycle. So far, the investigation of the role of amino acids at the active site was hampered by the lack of a suitable expression system that allowed for detailed site-directed mutagenesis studies at the active site. Here, we report on the establishment of a functional heterologous expression system of O. carboxidovorans CODH in Escherichia coli. We characterize the purified enzyme in detail by a combination of kinetic and spectroscopic studies and show that it was purified in a form with characteristics comparable to those of the native enzyme purified from O. carboxidovorans. With this expression system in hand, we were for the first time able to generate active-site variants of this enzyme. Our work presents the basis for more detailed studies of the reaction mechanism for CO and H-2 oxidation of Mo/Cu-dependent CODHs in the future.
Y1 - 2018
U6 - https://doi.org/10.1021/acs.biochem.8b00128
SN - 0006-2960
VL - 57
IS - 19
SP - 2889
EP - 2901
PB - American Chemical Society
CY - Washington
ER -
TY - JOUR
A1 - Vanneste, Thomas
A1 - Valdes, Alicia
A1 - Verheyen, Kris
A1 - Perring, Michael P.
A1 - Bernhardt-Roemermann, Markus
A1 - Andrieu, Emilie
A1 - Brunet, Jorg
A1 - Cousins, Sara A. O.
A1 - Deconchat, Marc
A1 - De Smedt, Pallieter
A1 - Diekmann, Martin
A1 - Ehrmann, Steffen
A1 - Heinken, Thilo
A1 - Hermy, Martin
A1 - Kolb, Annette
A1 - Lenoir, Jonathan
A1 - Liira, Jaan
A1 - Naaf, Tobias
A1 - Paal, Taavi
A1 - Wulf, Monika
A1 - Decocq, Guillaume
A1 - De Frenne, Pieter
T1 - Functional trait variation of forest understorey plant communities across Europe
JF - Basic and applied ecology : Journal of the Gesellschaft für Ökologie
N2 - Global environmental changes are expected to alter the functional characteristics of understorey herb-layer communities, potentially affecting forest ecosystem functioning. However, little is known about what drives the variability of functional traits in forest understories. Here, we assessed the role of different environmental drivers in shaping the functional trait distribution of understorey herbs in fragmented forests across three spatial scales. We focused on 708 small, deciduous forest patches located in 16 agricultural landscape windows, spanning a 2500-km macroclimatic gradient across the temperate forest biome in Europe. We estimated the relative effect of patch-scale, landscape-scale and macroclimatic variables on the community mean and variation of plant height, specific leaf area and seed mass. Macroclimatic variables (monthly temperature and precipitation extremes) explained the largest proportion of variation in community trait means (on average 77% of the explained variation). In contrast, patch-scale factors dominated in explaining community trait variation (on average 68% of the explained variation). Notably, patch age, size and internal heterogeneity had a positive effect on the community-level variability. Landscape-scale variables explained only a minor part of the variation in both trait distribution properties. The variation explained by shared combinations of the variable groups was generally negligible. These findings highlight the importance of considering multiple spatial scales in predictions of environmental-change effects on the functionality of forest understories. We propose that forest management sustainability could benefit from conserving larger, historically continuous and internally heterogeneous forest patches to maximise ecosystem service diversity in rural landscapes. (C) 2018 Gesellschaft fur Okologie. Published by Elsevier GmbH. All rights reserved.
KW - Agricultural landscapes
KW - Biogeography
KW - Community ecology
KW - Forest understorey
KW - Functional trait diversity
KW - Fragmentation
KW - Global environmental change
KW - Landscape connectivity
KW - Macroclimatic gradient
KW - Multi-scale analysis
Y1 - 2018
U6 - https://doi.org/10.1016/j.baae.2018.09.004
SN - 1439-1791
SN - 1618-0089
VL - 34
SP - 1
EP - 14
PB - Elsevier GmbH
CY - München
ER -
TY - THES
A1 - Albers, Philip
T1 - Funktionelle Charakterisierung des bakteriellen Typ-III Effektorproteins HopZ1a in Nicotiana benthamiana
T1 - Functional characterization of the bacterial type-III effector protein HopZ1a in Nicotiana benthamiana
N2 - Um das Immunsystem der Pflanze zu manipulieren translozieren gram-negative pathogene Bakterien Typ-III Effektorproteine (T3E) über ein Typ-III Sekretionssystem (T3SS) in die pflanzliche Wirtszelle. Dort lokalisieren T3Es in verschiedenen subzellulären Kompartimenten, wo sie Zielproteine modifizieren und so die Infektion begünstigen. HopZ1a, ein T3E des Pflanzenpathogens Pseudomonas syringae pv. syringae, ist eine Acetyltransferase und lokalisiert über ein Myristolierungsmotiv an der Plasmamembran der Wirtszelle. Obwohl gezeigt wurde, dass HopZ1a die frühe Signalweiterleitung an der Plasmamembran stört, wurde bisher kein mit der Plasmamembran assoziiertes Zielprotein für diesen T3E identifiziert. Um bisher unbekannte HopZ1a-Zieleproteine zu identifizieren wurde im Vorfeld dieser Arbeit eine Hefe-Zwei-Hybrid-Durchmusterung mit einer cDNA-Bibliothek aus Tabak durchgeführt, wobei ein nicht näher charakterisiertes Remorin als Interaktor gefunden wurde.
Bei dem Remorin handelt es sich um einen Vertreter der Gruppe 4 der Remorin-Familie, weshalb es in NbREM4 umbenannt wurde. Durch den Einsatz verschiedener Interaktionsstudien konnte demonstriert werden, dass HopZ1a mit NbREM4 in Hefe, in vitro und in planta wechselwirkt. Es wurde ferner deutlich, dass HopZ1a auf spezifische Weise mit dem konservierten C-Terminus von NbREM4 interagiert, das Remorin jedoch in vitro nicht acetyliert. Analysen mittels BiFC haben zudem ergeben, dass NbREM4 in Homodimeren an der Plasmamembran lokalisiert, wo auch die Interaktion mit HopZ1a stattfindet.
Eine funktionelle Charakterisierung von NbREM4 ergab, dass das Remorin eine spezifische Rolle im Immunsystem der Pflanze einnimmt. Die transiente Expression in N. benthamiana induziert die Expression von Abwehrgenen sowie einen veränderten Blattphänotyp. In A. thaliana wird HopZ1a über das Decoy ZED1 und das R-Protein ZAR1 erkannt, was zur Auslösung einer starken Hypersensitiven Antwort (HR von hypersensitive response) führt. Es konnte im Rahmen dieser Arbeit gezeigt werden, dass ZAR1 in N. benthamiana konserviert ist, NbREM4 jedoch nicht in der ETI als Decoy fungiert. Mit Hilfe einer Hefe-Zwei-Hybrid-Durchmusterung mit NbZAR1 als Köder konnten zwei Proteine, die Catalase CAT1 und der Protonenpumpeninteraktor PPI1, als Interaktoren von NbZAR1 identifiziert werden, welche möglicherweise in der Regulation der HR eine Rolle spielen.
Aus Voruntersuchungen war bekannt, dass NbREM4 mit weiteren, nicht näher charakterisierten Proteinen aus Tabak interagieren könnte. Eine phylogenetische Einordnung hat gezeigt, dass es sich um die bekannte Immun-Kinase PBS1 sowie zwei E3-Ubiquitin-Ligasen, NbSINA1 und NbSINAL3, handelt. PBS1 interagiert mit NbREM4 an der Plasmamembran und phosphoryliert das Remorin innerhalb des intrinsisch ungeordneten N-Terminus. Mittels Massenspektrometrie konnten die Serine an Position 64 und 65 innerhalb der Aminosäuresequenz von NbREM4 als PBS1-abhängige Phosphorylierungsstellen identifiziert wurden.
NbSINA1 und NbSINAL3 besitzen in vitro Ubiquitinierungsaktivität, bilden Homo- und Heterodimere und interagieren ebenfalls mit dem N-terminalen Teil von NbREM4, wobei sie das Remorin in vitro nicht ubiquitinieren.
Aus den in dieser Arbeit gewonnenen Ergebnissen lässt sich ableiten, dass der bakterielle T3E HopZ1a gezielt mit dem Tabak-Remorin NbREM4 an der Plasmamembran interagiert und über einen noch unbekannten Mechanismus mit dem Immunsystem der Pflanze interferiert, wobei NbREM4 möglicherweise eine Rolle als Adapter- oder Ankerprotein zukommt, über welches HopZ1a mit weiteren Immunkomponenten interagiert. NbREM4 ist Teil eines größeren Immunnetzwerkes, zu welchem die bekannte Immun-Kinase PBS1 und zwei E3-Ubiquitin-Ligasen gehören. Mit NbREM4 konnte damit erstmalig ein membranständiges Protein mit einer Funktion im Immunsystem der Pflanze als Zielprotein von HopZ1a identifiziert werden.
N2 - In order to manipulate the plant's immune system, gram-negative pathogenic bacteria inject type-III effector proteins (T3E) via a type III secretion system (T3SS) into the plant host cell. Inside the cell, T3Es localize to different subcellular compartments, where they modify target proteins and thereby promote the infection. HopZ1a, a T3E of the plant pathogen Pseudomonas syringae pv. syringae is an acetyltransferase and localizes to the plasma membrane. Although it has been shown that HopZ1a interferes with early signal transduction at the plasma membrane, no dedicated plasma membrane-associated target protein has been identified so far.
To identify unknown HopZ1a target proteins, a yeast two-hybrid screening using a cDNA library from tobacco was performed in advance of this work. The screen identified a previously uncharacterized remorin-family protein as a putative interactor of HopZ1a.
Using phylogenetic analyses, the remorin could be classified as a group 4 remorin family member and therefore was renamed NbREM4. By using different interaction studies, it has could be demonstrated that HopZ1a interacts with NbREM4 in yeast, in vitro, and in planta. It also became evident that HopZ1a specifically interacts with the conserved C-terminus of NbREM4 but does not acetylate it. BiFC analyses showed that NbREM4 localizes in homodimers at the plasma membrane, and NbREM4 interacts with HopZ1a in this subcellular compartment.
From preliminary studies it was known that NbREM4 may interact with other uncharacterized proteins from tobacco. A phylogenetic analysis revealed the immune kinase NbPBS1 and two E3 ubiquitin ligases, NbSINA1 and NbSINAL3, as putative NbREM4 interacting proteins. Analysis showed that NbPBS1 interacts with NbREM4 at the plasma membrane and phosphorylates the Remorin within the intrinsically disordered N-terminus. By means of mass spectrometry, serines at position 64 and 65 within the amino acid sequence of NbREM4 were identified as PBS1-dependent phosphorylation sites.
NbSINA1 and NbSINAL3 have in vitro ubiquitination activity and also interact with the N-terminal part of NbREM4, but do not ubiquitinate it.
It has already been shown that, in Arabidopsis thaliana, HopZ1a is recognized by the R protein ZAR1. In the presence of the effector, ZAR1 induces a strong hypersensitive response (HR) of the cell. In this study it could be confirmed that ZAR1 is conserved in Nicotiana benthamiana and is also responsible for the recognition of HopZ1a. In addition, a yeast two-hybrid screen revealed the catalase CAT1 and the proton pump interactor PPI1 as putative NbZAR1-interacting proteins, possibly contributing to the downstream activation of HR.
From the results obtained in this work, it can be deduced that the bacterial T3E HopZ1a specifically interacts with the Remorin NbREM4 at the plasma membrane and interferes with the immune system via a yet unknown mechanism. NbREM4 is part of a larger immune network that includes NbPBS1 and two E3 ligases. With NbREM4, the first membrane-associated target protein of HopZ1a could have been identified.
KW - Pseudomonas syringae
KW - Remorin
KW - HopZ1a
KW - PBS1
KW - pflanzliches Immunsystem
KW - Pseudomonas syringae
KW - Remorin
KW - HopZ1a
KW - PBS1
KW - plant immune system
Y1 - 2018
ER -
TY - JOUR
A1 - Schlör, Anja
A1 - Holzlöhner, Pamela
A1 - Listek, Martin
A1 - Grieß, Cindy
A1 - Butze, Monique
A1 - Micheel, Burkhard
A1 - Hentschel, Christian
A1 - Sowa, Mandy
A1 - Roggenbuck, Dirk
A1 - Schierack, Peter
A1 - Füner, Jonas
A1 - Schliebs, Erik
A1 - Goihl, Alexander
A1 - Reinhold, Dirk
A1 - Hanack, Katja
T1 - Generation and validation of murine monoclonal and camelid recombinant single domain antibodies specific for human pancreatic glycoprotein 2
JF - New biotechnology
N2 - Pancreatic secretory zymogen-granule membrane glycoprotein 2 (GP2) has been identified as a major autoantigenic target in Crohn’s disease patients. It was reported recently that a long (GP2a) and a short (GP2b) isoform of GP2 exist and that in the outcome of inflammatory bowel diseases (IBD) GP2-specific autoantibodies probably appear as new serological markers for diagnosis and therapeutic monitoring. To investigate this further and in order to establish diagnostic tools for the discrimination of both GP2 isoforms, a set of different murine monoclonal and camelid recombinant single domain antibodies (camelid VHH) was generated and validated in various enzyme-linked immunosorbent assay (ELISA) formats, immunofluorescence on transgenic cell lines and immunohistochemistry on monkey pancreas tissue sections. Out of six binders identified, one was validated as highly specific for GP2a. This murine monoclonal antibody (mAb) was used as capture antibody in construction of a sandwich ELISA for the detection of GP2a. Camelid VHHs or a second murine mAb served as detection antibodies in this system. All antibodies were also able to stain GP2a or GP2b on transgenic cell lines as well as on pancreatic tissue in immunohistochemistry. The KD values measured for the camelid VHHs were between 7 nM and 23pM. This set of specific binders will enable the development of suitable diagnostic tools for GP2-related studies in IBD.
KW - glycoprotein GP2
KW - Monoclonal antibodies
KW - Camelid single domain antibodies
Y1 - 2018
U6 - https://doi.org/10.1016/j.nbt.2018.03.006
SN - 1871-6784
SN - 1876-4347
VL - 45
SP - 60
EP - 68
PB - Elsevier
CY - Amsterdam
ER -
TY - JOUR
A1 - Holzlöhner, Pamela
A1 - Butze, Monique
A1 - Maier, Natalia
A1 - Hebel, Nicole
A1 - Schliebs, Erik
A1 - Micheel, Burkhard
A1 - Fuener, Jonas
A1 - Heidicke, Gabriele
A1 - Hanack, Katja
T1 - Generation of murine monoclonal antibodies with specificity against conventional camelid IgG1 and heavy-chain only IgG2/3
JF - Veterinary Immunology and Immunopathology
N2 - Camelids possess antibodies with a conventional four-chain structure consisting of two heavy and two light chains (of subclass IgG1) but further they also generate heavy-chain only antibodies (of subclass IgG2 and 3) which are fully functional in antigen binding. In this study subclass-specific murine monoclonal antibodies specific to conventional camelid IgG1 and heavy-chain only IgG2/3 were generated and validated for the use as potent secondary detection reagents. The monoclonal antibodies are able to differentiate between all camelid IgGs, conventional four-chain camelid antibodies (of subclass IgG1) and exclusively heavy chain-only antibodies (of subclasses IgG2 and IgG3). Further these antibodies were used to detect specific immune responses after vaccination of Camelids against bovine corona- and rotavirus strains and different E.coli. and Clostridia - antigens and to identify Erysipelothrix rhusiopathiae infected animals within a herd. The described antibodies are suitable as new secondary agents for the detection of different camelid subclasses and the validation of camelid immune reactions.
KW - Camelid antibodies
KW - Heavy-chain only antibodies
KW - Monoclonal antibodies
KW - Secondary antibodies
KW - Vaccination
KW - Disease monitoring
Y1 - 2018
U6 - https://doi.org/10.1016/j.vetimm.2018.01.006
SN - 0165-2427
SN - 1873-2534
VL - 197
SP - 1
EP - 6
PB - Elsevier
CY - Amsterdam
ER -
TY - JOUR
A1 - Laitinen, Roosa A. E.
A1 - Nikoloski, Zoran
T1 - Genetic basis of plasticity in plants
JF - Journal of experimental botany
N2 - The ability of an organism to change its phenotype in response to different environments, termed plasticity, is a particularly important characteristic to enable sessile plants to adapt to rapid changes in their surroundings. Plasticity is a quantitative trait that can provide a fitness advantage and mitigate negative effects due to environmental perturbations. Yet, its genetic basis is not fully understood. Alongside technological limitations, the main challenge in studying plasticity has been the selection of suitable approaches for quantification of phenotypic plasticity. Here, we propose a categorization of the existing quantitative measures of phenotypic plasticity into nominal and relative approaches. Moreover, we highlight the recent advances in the understanding of the genetic architecture underlying phenotypic plasticity in plants. We identify four pillars for future research to uncover the genetic basis of phenotypic plasticity, with emphasis on development of computational approaches and theories. These developments will allow us to perform specific experiments to validate the causal genes for plasticity and to discover their role in plant fitness and evolution.
KW - Genetic architecture
KW - GWA
KW - GxE interaction
KW - hub genes
KW - plant adaptation
KW - plasticity
KW - variance
Y1 - 2018
U6 - https://doi.org/10.1093/jxb/ery404
SN - 0022-0957
SN - 1460-2431
VL - 70
IS - 3
SP - 739
EP - 745
PB - Oxford Univ. Press
CY - Oxford
ER -
TY - JOUR
A1 - Beaumont, Robin N.
A1 - Warrington, Nicole M.
A1 - Cavadino, Alana
A1 - Tyrrell, Jessica
A1 - Nodzenski, Michael
A1 - Horikoshi, Momoko
A1 - Geller, Frank
A1 - Myhre, Ronny
A1 - Richmond, Rebecca C.
A1 - Paternoster, Lavinia
A1 - Bradfield, Jonathan P.
A1 - Kreiner-Moller, Eskil
A1 - Huikari, Ville
A1 - Metrustry, Sarah
A1 - Lunetta, Kathryn L.
A1 - Painter, Jodie N.
A1 - Hottenga, Jouke-Jan
A1 - Allard, Catherine
A1 - Barton, Sheila J.
A1 - Espinosa, Ana
A1 - Marsh, Julie A.
A1 - Potter, Catherine
A1 - Zhang, Ge
A1 - Ang, Wei
A1 - Berry, Diane J.
A1 - Bouchard, Luigi
A1 - Das, Shikta
A1 - Hakonarson, Hakon
A1 - Heikkinen, Jani
A1 - Helgeland, Oyvind
A1 - Hocher, Berthold
A1 - Hofman, Albert
A1 - Inskip, Hazel M.
A1 - Jones, Samuel E.
A1 - Kogevinas, Manolis
A1 - Lind, Penelope A.
A1 - Marullo, Letizia
A1 - Medland, Sarah E.
A1 - Murray, Anna
A1 - Murray, Jeffrey C.
A1 - Njolstad, Pal R.
A1 - Nohr, Ellen A.
A1 - Reichetzeder, Christoph
A1 - Ring, Susan M.
A1 - Ruth, Katherine S.
A1 - Santa-Marina, Loreto
A1 - Scholtens, Denise M.
A1 - Sebert, Sylvain
A1 - Sengpiel, Verena
A1 - Tuke, Marcus A.
A1 - Vaudel, Marc
A1 - Weedon, Michael N.
A1 - Willemsen, Gonneke
A1 - Wood, Andrew R.
A1 - Yaghootkar, Hanieh
A1 - Muglia, Louis J.
A1 - Bartels, Meike
A1 - Relton, Caroline L.
A1 - Pennell, Craig E.
A1 - Chatzi, Leda
A1 - Estivill, Xavier
A1 - Holloway, John W.
A1 - Boomsma, Dorret I.
A1 - Montgomery, Grant W.
A1 - Murabito, Joanne M.
A1 - Spector, Tim D.
A1 - Power, Christine
A1 - Jarvelin, Marjo-Ritta
A1 - Bisgaard, Hans
A1 - Grant, Struan F. A.
A1 - Sorensen, Thorkild I. A.
A1 - Jaddoe, Vincent W.
A1 - Jacobsson, Bo
A1 - Melbye, Mads
A1 - McCarthy, Mark I.
A1 - Hattersley, Andrew T.
A1 - Hayes, M. Geoffrey
A1 - Frayling, Timothy M.
A1 - Hivert, Marie-France
A1 - Felix, Janine F.
A1 - Hypponen, Elina
A1 - Lowe, William L.
A1 - Evans, David M.
A1 - Lawlor, Debbie A.
A1 - Feenstra, Bjarke
A1 - Freathy, Rachel M.
T1 - Genome-wide association study of offspring birth weight in 86 577 women identifies five novel loci and highlights maternal genetic effects that are independent of fetal genetics
JF - Human molecular genetics
N2 - Genome-wide association studies of birth weight have focused on fetal genetics, whereas relatively little is known about the role of maternal genetic variation. We aimed to identify maternal genetic variants associated with birth weight that could highlight potentially relevant maternal determinants of fetal growth. We meta-analysed data on up to 8.7 million SNPs in up to 86 577 women of European descent from the Early Growth Genetics (EGG) Consortium and the UK Biobank. We used structural equation modelling (SEM) and analyses of mother-child pairs to quantify the separate maternal and fetal genetic effects. Maternal SNPs at 10 loci (MTNR1B, HMGA2, SH2B3, KCNAB1, L3MBTL3, GCK, EBF1, TCF7L2, ACTL9, CYP3A7) were associated with offspring birth weight at P< 5 x 10(-8). In SEM analyses, at least 7 of the 10 associations were consistent with effects of the maternal genotype acting via the intrauterine environment, rather than via effects of shared alleles with the fetus. Variants, or correlated proxies, at many of the loci had been previously associated with adult traits, including fasting glucose (MTNR1B, GCK and TCF7L2) and sex hormone levels (CYP3A7), and one (EBF1) with gestational duration. The identified associations indicate that genetic effects on maternal glucose, cytochrome P450 activity and gestational duration, and potentially on maternal blood pressure and immune function, are relevant for fetal growth. Further characterization of these associations in mechanistic and causal analyses will enhance understanding of the potentially modifiable maternal determinants of fetal growth, with the goal of reducing the morbidity and mortality associated with low and high birth weights.
Y1 - 2018
U6 - https://doi.org/10.1093/hmg/ddx429
SN - 0964-6906
SN - 1460-2083
VL - 27
IS - 4
SP - 742
EP - 756
PB - Oxford Univ. Press
CY - Oxford
ER -
TY - JOUR
A1 - Perring, Michael P.
A1 - Bernhardt-Roemermann, Markus
A1 - Baeten, Lander
A1 - Midolo, Gabriele
A1 - Blondeel, Haben
A1 - Depauw, Leen
A1 - Landuyt, Dries
A1 - Maes, Sybryn L.
A1 - De Lombaerde, Emiel
A1 - Caron, Maria Mercedes
A1 - Vellend, Mark
A1 - Brunet, Joerg
A1 - Chudomelova, Marketa
A1 - Decocq, Guillaume
A1 - Diekmann, Martin
A1 - Dirnboeck, Thomas
A1 - Doerfler, Inken
A1 - Durak, Tomasz
A1 - De Frenne, Pieter
A1 - Gilliam, Frank S.
A1 - Hedl, Radim
A1 - Heinken, Thilo
A1 - Hommel, Patrick
A1 - Jaroszewicz, Bogdan
A1 - Kirby, Keith J.
A1 - Kopecky, Martin
A1 - Lenoir, Jonathan
A1 - Li, Daijiang
A1 - Malis, Frantisek
A1 - Mitchell, Fraser J. G.
A1 - Naaf, Tobias
A1 - Newman, Miles
A1 - Petrik, Petr
A1 - Reczynska, Kamila
A1 - Schmidt, Wolfgang
A1 - Standovar, Tibor
A1 - Swierkosz, Krzysztof
A1 - Van Calster, Hans
A1 - Vild, Ondrej
A1 - Wagner, Eva Rosa
A1 - Wulf, Monika
A1 - Verheyen, Kris
T1 - Global environmental change effects on plant community composition trajectories depend upon management legacies
JF - Global change biology
N2 - The contemporary state of functional traits and species richness in plant communities depends on legacy effects of past disturbances. Whether temporal responses of community properties to current environmental changes are altered by such legacies is, however, unknown. We expect global environmental changes to interact with land-use legacies given different community trajectories initiated by prior management, and subsequent responses to altered resources and conditions. We tested this expectation for species richness and functional traits using 1814 survey-resurvey plot pairs of understorey communities from 40 European temperate forest datasets, syntheses of management transitions since the year 1800, and a trait database. We also examined how plant community indicators of resources and conditions changed in response to management legacies and environmental change. Community trajectories were clearly influenced by interactions between management legacies from over 200 years ago and environmental change. Importantly, higher rates of nitrogen deposition led to increased species richness and plant height in forests managed less intensively in 1800 (i.e., high forests), and to decreases in forests with a more intensive historical management in 1800 (i.e., coppiced forests). There was evidence that these declines in community variables in formerly coppiced forests were ameliorated by increased rates of temperature change between surveys. Responses were generally apparent regardless of sites’ contemporary management classifications, although sometimes the management transition itself, rather than historic or contemporary management types, better explained understorey responses. Main effects of environmental change were rare, although higher rates of precipitation change increased plant height, accompanied by increases in fertility indicator values. Analysis of indicator values suggested the importance of directly characterising resources and conditions to better understand legacy and environmental change effects. Accounting for legacies of past disturbance can reconcile contradictory literature results and appears crucial to anticipating future responses to global environmental change.
KW - biodiversity change
KW - climate change
KW - disturbance regime
KW - forestREplot
KW - herbaceous layer
KW - management intensity
KW - nitrogen deposition
KW - plant functional traits
KW - time lag
KW - vegetation resurvey
Y1 - 2017
U6 - https://doi.org/10.1111/gcb.14030
SN - 1354-1013
SN - 1365-2486
VL - 24
IS - 4
SP - 1722
EP - 1740
PB - Wiley
CY - Hoboken
ER -
TY - JOUR
A1 - Omidbakhshfard, Mohammad Amin
A1 - Fujikura, Ushio
A1 - Olas, Justyna Jadwiga
A1 - Xue, Gang-Ping
A1 - Balazadeh, Salma
A1 - Mueller-Roeber, Bernd
T1 - GROWTH-REGULATING FACTOR 9 negatively regulates arabidopsis leaf growth by controlling ORG3 and restricting cell proliferation in leaf primordia
JF - PLoS Genetics : a peer-reviewed, open-access journal
N2 - Leaf growth is a complex process that involves the action of diverse transcription factors (TFs) and their downstream gene regulatory networks. In this study, we focus on the functional characterization of the Arabidopsis thaliana TF GROWTH-REGULATING FACTOR9 (GRF9) and demonstrate that it exerts its negative effect on leaf growth by activating expression of the bZIP TF OBP3-RESPONSIVE GENE 3 (ORG3). While grf9 knockout mutants produce bigger incipient leaf primordia at the shoot apex, rosette leaves and petals than the wild type, the sizes of those organs are reduced in plants overexpressing GRF9 (GRF9ox). Cell measurements demonstrate that changes in leaf size result from alterations in cell numbers rather than cell sizes. Kinematic analysis and 5-ethynyl-2'-deoxyuridine (EdU) incorporation assay revealed that GRF9 restricts cell proliferation in the early developing leaf. Performing in vitro binding site selection, we identified the 6-base motif 5'-CTGACA-3' as the core binding site of GRF9. By global transcriptome profiling, electrophoretic mobility shift assay (EMSA) and chromatin immunoprecipitation (ChIP) we identified ORG3 as a direct downstream, and positively regulated target of GRF9. Genetic analysis of grf9 org3 and GRF9ox org3 double mutants reveals that both transcription factors act in a regulatory cascade to control the final leaf dimensions by restricting cell number in the developing leaf.
Y1 - 2018
U6 - https://doi.org/10.1371/journal.pgen.1007484
SN - 1553-7404
VL - 14
IS - 7
PB - PLoS
CY - San Fransisco
ER -
TY - JOUR
A1 - Mayer, Martin
A1 - Ullmann, Wiebke
A1 - Sunde, Peter
A1 - Fischer, Christina
A1 - Blaum, Niels
T1 - Habitat selection by the European hare in arable landscapes
BT - The importance of small-scale habitat structure for conservation
JF - Ecology and Evolution
N2 - Agricultural land-use practices have intensified over the last decades, leading to population declines of various farmland species, including the European hare (Lepus europaeus). In many European countries, arable fields dominate agricultural landscapes. Compared to pastures, arable land is highly variable, resulting in a large spatial variation of food and cover for wildlife over the course of the year, which potentially affects habitat selection by hares. Here, we investigated within-home-range habitat selection by hares in arable areas in Denmark and Germany to identify habitat requirements for their conservation. We hypothesized that hare habitat selection would depend on local habitat structure, that is, vegetation height, but also on agricultural field size, vegetation type, and proximity to field edges. Active hares generally selected for short vegetation (1-25 cm) and avoided higher vegetation and bare ground, especially when fields were comparatively larger. Vegetation >50 cm potentially restricts hares from entering parts of their home range and does not provide good forage, the latter also being the case on bare ground. The vegetation type was important for habitat selection by inactive hares, with fabaceae, fallow, and maize being selected for, potentially providing both cover and forage. Our results indicate that patches of shorter vegetation could improve the forage quality and habitat accessibility for hares, especially in areas with large monocultures. Thus, policymakers should aim to increase areas with short vegetation throughout the year. Further, permanent set-asides, like fallow and wildflower areas, would provide year-round cover for inactive hares. Finally, the reduction in field sizes would increase the density of field margins, and farming different crop types within small areas could improve the habitat for hares and other farmland species.
KW - agriculture
KW - arable land
KW - conservation
KW - GPS
KW - habitat selection
KW - Lepus europaeus
KW - vegetation height
Y1 - 2018
U6 - https://doi.org/10.1002/ece3.4613
SN - 2045-7758
VL - 8
IS - 23
SP - 11619
EP - 11633
PB - Wiley
CY - Hoboken
ER -
TY - JOUR
A1 - Reil, Daniela
A1 - Binder, Florian
A1 - Freise, Jona
A1 - Imholt, Christian
A1 - Beyrers, Konrad
A1 - Jacob, Jens
A1 - Krüger, Detlev H.
A1 - Hofmann, Jörg
A1 - Dreesman, Johannes
A1 - Ulrich, Rainer Günter
T1 - Hantaviren in Deutschland
BT - Aktuelle Erkenntnisse zu Erreger, Reservoir, Verbreitung und Prognosemodellen
JF - Berliner und Münchener tierärztliche Wochenschrift
N2 - Hantaviruses are small mammal-associated pathogens that are found in rodents but also in shrews, moles and bats. Aim of this manuscript is to give a current overview of the epidemiology and ecology of hantaviruses in Germany and to discuss respective models for the prediction of virus outbreaks. In Germany the majority of human disease cases are caused by the Puumala virus (PUUV), transmitted by the bank vole (Myodes glareolus). PUUV is associated with the Western evolutionary lineage of the bank vole and is not present in the eastern and northern parts of Germany. A second human pathogenic hantavirus is the Dobrava-Belgrade virus (DOBV), genotype Kurkino; its reservoir host, the striped field mouse (Apodemus agrarius), is mostly occurring in the eastern part of Germany. A PUUV-related hantavirus is the rarely pathogenic Tula virus (TULV), that is associated with the common vole (Microtus arvalis). In addition, Seewis virus, Asikkala virus, and Bruges virus are shrew- and mole-associated hantaviruses with still unknown pathogenicity in humans. Human disease cases are associated with the different hantaviruses according to their regional distribution. The viruses can cause mild to severe but also subclinical courses of the respective disease. The number of human PUUV disease cases in 2007, 2010, 2012, 2015 and 2017 correlates with the occurrence of high levels of seed production of beech trees ("beech mast") in the preceding year. Models based on weather parameters for the prediction of PUUV disease clusters as developed in recent years need further validation and optimisation. in addition to the abundance of infected reservoir rodents, the exposure behaviour of humans affects the risk of human infection. The application of robust forecast models can assist the public health service to develop and communicate spatially and temporally targeted information. Thus, further recommendations to mitigate infection risk for the public may be provided.
N2 - Hantaviren sind Kleinsäuger-assoziierte Krankheitserreger, die vor allem in Nagetieren, aber auch in Spitzmäusen, Maulwürfen und Fledermäusen vorkommen. Ziel dieser Arbeit ist es, einen aktuellen Überblick zur Epidemiologie und Ökologie der Hantaviren in Deutschland zu geben und Modelle zur Vorhersage von Virusausbrüchen zu diskutieren. In Deutschland werden die meisten humanen Erkrankungsfälle beim Menschen durch das von der Rötelmaus (Myodes glareolus) übertragene Puumalavirus (PUUV) verursacht. PUUV ist mit der westlichen evolutionären Linie der Rötelmaus assoziiert und fehlt im östlichen und nördlichen Teil Deutschlands. Ein zweites humanpathogenes Hantavirus ist das Dobrava-Belgrad-Virus (DOBV), Genotyp Kurkino, dessen Reservoir die vor allem im östlichen Teil Deutschlands vorkommende Brandmaus (Apodemus agrarius) ist. Ein PUUV-verwandtes Hantavirus ist das selten humanpathogene Tulavirus (TULV), das mit der Feldmaus (Microtus arvalis) assoziiert ist. Darüber hinaus wurden mit dem Seewis-, Asikkala- und Brugesvirus Spitzmaus- und Maulwurf-assoziierte Hantaviren mit noch unklarer Humanpathogenität gefunden.
Die humanen Erkrankungen sind jeweils mit den verschiedenen Hantaviren in deren regionaler Verteilung assoziiert und können mild bis schwer, aber auch subklinisch verlaufen. Das Auftreten von Häufungen humaner, durch PUUV verursachter Erkrankungen in den Jahren 2007, 2010, 2012, 2015 und 2017 korreliert mit dem Auftreten einer starken Fruktifikation der Buche („Buchenmast“) im jeweiligen Vorjahr. Auf der Basis von Wetterparametern sind Modelle zur Vorhersage von PUUV-Erkrankungshäufungen entwickelt worden, die zukünftig validiert und optimiert werden müssen. Neben dem Ausmaß des Virusvorkommens im Reservoir wird das Risiko humaner Infektionen durch das Expositionsverhalten des Menschen beeinflusst. Durch die Anwendung von Prognosemodellen soll der öffentliche Gesundheitsdienst in die Lage versetzt werden, räumlich und zeitlich gezielte und sachgerechte Präventionsempfehlungen für die Bevölkerung abzugeben.
T2 - Hantaviruses in Germany: current knowledge on pathogens, reservoirs, distribution and forecast models
KW - early warning system
KW - hantavirus
KW - hantavirus disease
KW - rodents
KW - population dynamics
KW - Frühwarn-System
KW - Hantavirus
KW - Hantavirus-Erkrankung
KW - Nagetiere
KW - Populationsdynamik
Y1 - 2018
U6 - https://doi.org/10.2376/0005-9366-18003
SN - 0005-9366
SN - 1439-0299
VL - 131
IS - 11-12
SP - 453
EP - 464
PB - Schlütersche Verlagsgesellschaft mbH & Co. KG.
CY - Hannover
ER -
TY - JOUR
A1 - Donat, Stefan
A1 - Lourenco, Marta Sofia Rocha
A1 - Paolini, Alessio
A1 - Otten, Cecile
A1 - Renz, Marc
A1 - Abdelilah-Seyfried, Salim
T1 - Heg1 and Ccm1/2 proteins control endocardial mechanosensitivity during zebrafish valvulogenesis
JF - eLife
N2 - Endothelial cells respond to different levels of fluid shear stress through adaptations of their mechanosensitivity. Currently, we lack a good understanding of how this contributes to sculpting of the cardiovascular system. Cerebral cavernous malformation (CCM) is an inherited vascular disease that occurs when a second somatic mutation causes a loss of CCM1/KRIT1, CCM2, or CCM3 proteins. Here, we demonstrate that zebrafish Krit1 regulates the formation of cardiac valves. Expression of heg1, which encodes a binding partner of Krit1, is positively regulated by blood-flow. In turn, Heg1 stabilizes levels of Krit1 protein, and both Heg1 and Krit1 dampen expression levels of klf2a, a major mechanosensitive gene. Conversely, loss of Krit1 results in increased expression of klf2a and notch1b throughout the endocardium and prevents cardiac valve leaflet formation. Hence, the correct balance of blood-flow-dependent induction and Krit1 protein mediated repression of klf2a and notch1b ultimately shapes cardiac valve leaflet morphology.
Y1 - 2018
U6 - https://doi.org/10.7554/eLife.28939
SN - 2050-084X
VL - 7
PB - eLife Sciences Publications
CY - Cambridge
ER -
TY - JOUR
A1 - Ryll, Rene
A1 - Eiden, Martin
A1 - Heuser, Elisa
A1 - Weinhardt, Markus
A1 - Ziege, Madlen
A1 - Hoeper, Dirk
A1 - Groschup, Martin H.
A1 - Heckel, Gerald
A1 - Johne, Reimar
A1 - Ulrich, Rainer G.
T1 - Hepatitis E virus in feral rabbits along a rural-urban transect in Central Germany
JF - Infection, genetics and evolution : journal of molecular epidemiology and evolutionary genetics and infectious diseases (MEEGID)
N2 - Rabbit associated genotype 3 hepatitis E virus (HEV) strains were detected in feral, pet and farm rabbits in different parts of the world since 2009 and recently also in human patients. Here, we report a serological and molecular survey on 72 feral rabbits, collected along a rural-urban transect in and next to Frankfurt am Main, Central Germany. ELISA investigations revealed in 25 of 72 (34.7%) animals HEV-specific antibodies. HEV derived RNA was detected in 18 of 72 (25%) animals by reverse transcription-polymerase chain reaction assay. The complete genomes from two rabbitHEV-strains, one from a rural site and the other from an inner-city area, were generated by a combination of high-throughput sequencing, a primer walking approach and 5′- and 3′- rapid amplification of cDNA ends. Phylogenetic analysis of open reading frame (ORF)1-derived partial and complete ORF1/ORF2 concatenated coding sequences indicated their similarity to rabbit-associated HEV strains. The partial sequences revealed one cluster of closely-related rabbitHEV sequences from the urban trapping sites that is well separated from several clusters representing rabbitHEV sequences from rural trapping sites. The complete genome sequences of the two novel strains indicated similarities of 75.6–86.4% to the other 17 rabbitHEV sequences; the amino acid sequence identity of the concatenated ORF1/ORF2-encoded proteins reached 89.0–93.1%. The detection of rabbitHEV in an inner-city area with a high human population density suggests a high risk of potential human infection with the zoonotic rabbitHEV, either by direct or indirect contact with infected animals. Therefore, future investigations on the occurrence and frequency of human infections with rabbitHEV are warranted in populations with different contact to rabbits.
KW - European rabbit (Oryctolagus cuniculus)
KW - Hepatitis E virus
KW - Germany
KW - Inner-city area
KW - Rural habitat
KW - Zoonosis
Y1 - 2018
U6 - https://doi.org/10.1016/j.meegid.2018.03.019
SN - 1567-1348
SN - 1567-7257
VL - 61
SP - 155
EP - 159
PB - Elsevier
CY - Amsterdam
ER -
TY - JOUR
A1 - Kruse, Stefan
A1 - Epp, Laura Saskia
A1 - Wieczorek, Mareike
A1 - Pestryakova, Luidmila Agafyevna
A1 - Stoof-Leichsenring, Kathleen Rosemarie
A1 - Herzschuh, Ulrike
T1 - High gene flow and complex treeline dynamics of Larix Mill. stands on the Taymyr Peninsula (north-central Siberia) revealed by nuclear microsatellites
JF - Tree Genetics & Genomes
N2 - Arctic treelines are facing a strong temperature increase as a result of recent global warming, causing possible changes in forest extent, which will alter vegetation-climate feedbacks. However, the mode and strength of the response is rather unclear, as potential changes are happening in areas that are very remote and difficult to access, and empirical data are still largely lacking. Here, we assessed the current population structure and genetic differentiation of Larix Mill. tree stands within the northernmost latitudinal treeline reaching ~ 72° N in the southern lowlands of the Taymyr Peninsula (~ 100° E). We sampled 743 individuals belonging to different height classes (seedlings, saplings, trees) at 11 locations along a gradient from ‘single tree’ tundra over ‘forest line’ to ‘dense forest’ stands and conducted investigations applying eight highly polymorphic nuclear microsatellites. Results suggest a high diversity within sub-populations (HE = 0.826–0.893), coupled, however, with heterozygote deficits in all sub-populations, but pronounced in ‘forest line’ stands. Overall, genetic differentiation of sub-populations is low (FST = 0.005), indicating a region-wide high gene flow, although ‘forest line’ stands harbour few rare and private alleles, likely indicating greater local reproduction. ‘Single tree’ stands, located beyond the northern forest line, are currently not involved in treeline expansion, but show signs of a long-term refuge, namely asexual reproduction and change of growth-form from erect to creeping growth, possibly having persisted for thousands of years. The lack of differentiation between the sub-populations points to a sufficiently high dispersal potential, and thus a rapid northward migration of the Siberian arctic treeline under recent global warming seems potentially unconstrained, but observations show it to be unexpectedly slow.
KW - Larch
KW - Population genetics
KW - Boreal forests
KW - Tundra-taiga transition
KW - Range expansion
Y1 - 2018
U6 - https://doi.org/10.1007/s11295-018-1235-3
SN - 1614-2942
SN - 1614-2950
VL - 14
IS - 2
PB - Springer
CY - Heidelberg
ER -
TY - JOUR
A1 - Fischer, Stefan
A1 - Spierling, Nastasja G.
A1 - Heuser, Elisa
A1 - Kling, Christopher
A1 - Schmidt, Sabrina
A1 - Rosenfeld, Ulrike
A1 - Reil, Daniela
A1 - Imholt, Christian
A1 - Jacob, Jens
A1 - Ulrich, Rainer G.
A1 - Essbauer, Sandra
T1 - High prevalence of Rickettsia helvetica in wild small mammal populations in Germany
JF - Ticks and Tick-borne Diseases
N2 - Since the beginning of the 21st century, spotted fever rickettsioses are known as emerging diseases worldwide. Rickettsiae are obligately intracellular bacteria transmitted by arthropod vectors. The ecology of Rickettsia species has not been investigated in detail, but small mammals are considered to play a role as reservoirs. Aim of this study was to monitor rickettsiae in wild small mammals over a period of five years in four federal states of Germany. Initial screening of ear pinna tissues of 3939 animals by Pan-Rick real-time PCR targeting the citrate synthase (gltA) gene revealed 296 rodents of seven species and 19 shrews of two species positive for rickettsial DNA. Outer membrane protein gene (ompB, ompAIV) PCRs based typing resulted in the identification of three species: Rickettsia helvetica (90.9%) was found as the dominantly occurring species in the four investigated federal states, but Rickettsia felis (7.8%) and Rickettsia raoultii (1.3%) were also detected. The prevalence of Rickettsia spp. in rodents of the genus Apodemus was found to be higher (approximately 14%) than in all other rodent and shrew species at all investigated sites. General linear mixed model analyses indicated that heavier (older) individuals of yellow-necked mice and male common voles seem to contain more often rickettsial DNA than younger ones. Furthermore, rodents generally collected in forests in summer and autumn more often carried rickettsial DNA. In conclusion, this study indicated a high prevalence of R. helvetica in small mammal populations and suggests an age-dependent increase of the DNA prevalence in some of the species and in animals originating from forest habitats. The finding of R. helvetica and R. felis DNA in multiple small mammal species may indicate frequent trans-species transmission by feeding of vectors on different species. Further investigations should target the reason for the discrepancy between the high rickettsial DNA prevalence in rodents and the so far almost absence of clinical apparent human infections.
KW - Rickettsia helvetica
KW - Rodent
KW - Germany
KW - Age
KW - Reproduction
KW - Season
Y1 - 2018
U6 - https://doi.org/10.1016/j.ttbdis.2018.01.009
SN - 1877-959X
SN - 1877-9603
VL - 9
IS - 3
SP - 500
EP - 505
PB - Elsevier GMBH
CY - München
ER -
TY - JOUR
A1 - Autenrieth, Marijke
A1 - Hartmann, Stefanie
A1 - Lah, Ljerka
A1 - Roos, Anna
A1 - Dennis, Alice B.
A1 - Tiedemann, Ralph
T1 - High-quality whole-genome sequence of an abundant Holarctic odontocete, the harbour porpoise (Phocoena phocoena)
JF - Molecular ecology resources
N2 - The harbour porpoise (Phocoena phocoena) is a highly mobile cetacean found across the Northern hemisphere. It occurs in coastal waters and inhabits basins that vary broadly in salinity, temperature and food availability. These diverse habitats could drive subtle differentiation among populations, but examination of this would be best conducted with a robust reference genome. Here, we report the first harbour porpoise genome, assembled de novo from an individual originating in the Kattegat Sea (Sweden). The genome is one of the most complete cetacean genomes currently available, with a total size of 2.39 Gb and 50% of the total length found in just 34 scaffolds. Using 122 of the longest scaffolds, we were able to show high levels of synteny with the genome of the domestic cattle (Bos taurus). Our draft annotation comprises 22,154 predicted genes, which we further annotated through matches to the NCBI nucleotide database, GO categorization and motif prediction. Within the predicted genes, we have confirmed the presence of >20 genes or gene families that have been associated with adaptive evolution in other cetaceans. Overall, this genome assembly and draft annotation represent a crucial addition to the genomic resources currently available for the study of porpoises and Phocoenidae evolution, phylogeny and conservation.
KW - cetaceans
KW - genomics/proteomics
KW - mammals
KW - molecular evolution
Y1 - 2018
U6 - https://doi.org/10.1111/1755-0998.12932
SN - 1755-098X
SN - 1755-0998
VL - 18
IS - 6
SP - 1469
EP - 1481
PB - Wiley
CY - Hoboken
ER -
TY - JOUR
A1 - Martins, Renata F.
A1 - Schmidt, Anke
A1 - Lenz, Dorina
A1 - Wilting, Andreas
A1 - Fickel, Jörns
T1 - Historical biogeography of Rusa unicolor and R-timorensis
BT - Historical biogeography of Rusa unicolor and R. timorensis
JF - Ecology and evolution
N2 - In this study we compared the phylogeographic patterns of two Rusa species, Rusa unicolor and Rusa timorensis, in order to understand what drove and maintained differentiation between these two geographically and genetically close species and investigated the route of introduction of individuals to the islands outside of the Sunda Shelf. We analyzed full mitogenomes from 56 archival samples from the distribution areas of the two species and 18 microsatellite loci in a subset of 16 individuals to generate the phylogeographic patterns of both species. Bayesian inference with fossil calibration was used to estimate the age of each species and major divergence events. Our results indicated that the split between the two species took place during the Pleistocene, similar to 1.8Mya, possibly driven by adaptations of R. timorensis to the drier climate found on Java compared to the other islands of Sundaland. Although both markers identified two well-differentiated clades, there was a largely discrepant pattern between mitochondrial and nuclear markers. While nDNA separated the individuals into the two species, largely in agreement with their museum label, mtDNA revealed that all R. timorensis sampled to the east of the Sunda shelf carried haplotypes from R. unicolor and one Rusa unicolor from South Sumatra carried a R. timorensis haplotype. Our results show that hybridization occurred between these two sister species in Sundaland during the Late Pleistocene and resulted in human-mediated introduction of hybrid descendants in all islands outside Sundaland.
KW - Cervidae
KW - human introduction
KW - hybridization
KW - Phylogeography
KW - Sundaland
Y1 - 2017
U6 - https://doi.org/10.1002/ece3.3754
SN - 2045-7758
VL - 8
IS - 3
SP - 1465
EP - 1479
PB - Wiley
CY - Hoboken
ER -
TY - JOUR
A1 - Paijmans, Johanna L. A.
A1 - Barlow, Axel
A1 - Förster, Daniel W.
A1 - Henneberger, Kirstin
A1 - Meyer, Matthias
A1 - Nickel, Birgit
A1 - Nagel, Doris
A1 - Worsøe Havmøller, Rasmus
A1 - Baryshnikov, Gennady F.
A1 - Joger, Ulrich
A1 - Rosendahl, Wilfried
A1 - Hofreiter, Michael
T1 - Historical biogeography of the leopard (Panthera pardus) and its extinct Eurasian populations
JF - BMC Evolutionary Biology
N2 - Background
Resolving the historical biogeography of the leopard (Panthera pardus) is a complex issue, because patterns inferred from fossils and from molecular data lack congruence. Fossil evidence supports an African origin, and suggests that leopards were already present in Eurasia during the Early Pleistocene. Analysis of DNA sequences however, suggests a more recent, Middle Pleistocene shared ancestry of Asian and African leopards. These contrasting patterns led researchers to propose a two-stage hypothesis of leopard dispersal out of Africa: an initial Early Pleistocene colonisation of Asia and a subsequent replacement by a second colonisation wave during the Middle Pleistocene. The status of Late Pleistocene European leopards within this scenario is unclear: were these populations remnants of the first dispersal, or do the last surviving European leopards share more recent ancestry with their African counterparts?
Results
In this study, we generate and analyse mitogenome sequences from historical samples that span the entire modern leopard distribution, as well as from Late Pleistocene remains. We find a deep bifurcation between African and Eurasian mitochondrial lineages (~ 710 Ka), with the European ancient samples as sister to all Asian lineages (~ 483 Ka). The modern and historical mainland Asian lineages share a relatively recent common ancestor (~ 122 Ka), and we find one Javan sample nested within these.
Conclusions
The phylogenetic placement of the ancient European leopard as sister group to Asian leopards suggests that these populations originate from the same out-of-Africa dispersal which founded the Asian lineages. The coalescence time found for the mitochondrial lineages aligns well with the earliest undisputed fossils in Eurasia, and thus encourages a re-evaluation of the identification of the much older putative leopard fossils from the region. The relatively recent ancestry of all mainland Asian leopard lineages suggests that these populations underwent a severe population bottleneck during the Pleistocene. Finally, although only based on a single sample, the unexpected phylogenetic placement of the Javan leopard could be interpreted as evidence for exchange of mitochondrial lineages between Java and mainland Asia, calling for further investigation into the evolutionary history of this subspecies.
KW - Ancient DNA
KW - Hybridisation capture
KW - Leopards
KW - Mitochondrial genomes
KW - Mitogenomes
KW - mtDNA
KW - Palaeogenetics
KW - Panthera pardus
Y1 - 2018
U6 - https://doi.org/10.1186/s12862-018-1268-0
SN - 1471-2148
VL - 18
IS - 156
PB - BioMed Central und Springer
CY - London, Berlin und Heidelberg
ER -
TY - JOUR
A1 - Ambarli, Hüseyin
A1 - Mengüllüoğlu, Deniz
A1 - Fickel, Jörns
A1 - Förster, Daniel W.
T1 - Hotel AMANO Grand Central of brown bears in southwest Asia
JF - PeerJ
N2 - Genetic studies of the Eurasian brown bear (Ursus arctos) have so far focused on populations from Europe and North America, although the largest distribution area of brown bears is in Asia. In this study, we reveal population genetic parameters for the brown bear population inhabiting the Grand Kackar Mountains (GKM) in the north east of Turkey, western Lesser Caucasus. Using both hair (N = 147) and tissue samples (N = 7) collected between 2008 and 2014, we found substantial levels of genetic variation (10 microsatellite loci). Bear samples (hair) taken from rubbing trees worked better for genotyping than those from power poles, regardless of the year collected. Genotyping also revealed that bears moved between habitat patches, despite ongoing massive habitat alterations and the creation of large water reservoirs. This population has the potential to serve as a genetic reserve for future reintroduction in the Middle East. Due to the importance of the GKM population for on-going and future conservation actions, the impacts of habitat alterations in the region ought to be minimized; e.g., by establishing green bridges or corridors over reservoirs and major roads to maintain habitat connectivity and gene flow among populations in the Lesser Caucasus.
KW - Ursus arctos
KW - Microsatellite
KW - Conservation
KW - Anatolia
KW - Isolation
KW - Source population
KW - Noninvasive sampling
KW - Rubbing tree
KW - Turkey
Y1 - 2018
U6 - https://doi.org/10.7717/peerj.5660
SN - 2167-8359
VL - 6
PB - PeerJ Inc.
CY - London
ER -
TY - JOUR
A1 - Bogin, Barry
A1 - Varea, Carlos
A1 - Hermanussen, Michael
A1 - Scheffler, Christiane
T1 - Human life course biology
BT - a centennial perspective of scholarship on the human pattern of physical growth and its place in human biocultural evolution
JF - American journal of physical anthropology
KW - adolescence
KW - childhood
KW - life history
KW - menopause
KW - senescence
Y1 - 2018
U6 - https://doi.org/10.1002/ajpa.23357
SN - 0002-9483
SN - 1096-8644
VL - 165
IS - 4
SP - 834
EP - 854
PB - Wiley
CY - Hoboken
ER -
TY - JOUR
A1 - Brügger, Sandra Olivia
A1 - Gobet, Erika
A1 - Sigl, Michael
A1 - Osmont, Dimitri
A1 - Papina, Tatyana
A1 - Rudaya, Natalia
A1 - Schwikowski-Gigar, Margit
A1 - Tinner, Willy
T1 - Ice records provide new insights into climatic vulnerability of Central Asian forest and steppe communities
JF - Global and planetary change
N2 - Forest and steppe communities in the Altai region of Central Asia are threatened by changing climate and anthropogenic pressure. Specifically, increasing drought and grazing pressure may cause collapses of moisture-demanding plant communities, particularly forests. Knowledge about past vegetation and fire responses to climate and land use changes may help anticipating future ecosystem risks, given that it has the potential to disclose mechanisms and processes that govern ecosystem vulnerability. We present a unique paleoecological record from the high-alpine Tsambagarav glacier in the Mongolian Altai that provides novel large-scale information on vegetation, fire and pollution with an exceptional temporal resolution and precision. Our palynological record identifies several late-Holocene boreal forest expansions, contractions and subsequent recoveries. Maximum forest expansions occurred at 3000-2800 BC, 2400-2100 BC, and 1900-1800 BC. After 1800 BC mixed boreal forest communities irrecoverably declined. Fires reached a maximum at 1600 BC, 200 years after the final forest collapse. Our multiproxy data suggest that burning peaked in response to dead biomass accumulation resulting from forest diebacks. Vegetation and fire regimes partly decoupled from climate after 1700 AD, when atmospheric industrial pollution began, and land use intensified. We conclude that moisture availability was more important than temperature for past vegetation dynamics, in particular for forest loss and steppe expansion. The past Mongolian Altai evidence implies that in the future forests of the Russian Altai may collapse in response to reduced moisture availability.
KW - Boreal forest diebacks
KW - Climatic tipping points
KW - Diversity
KW - Ice core
KW - Moisture change
KW - Pollen
KW - Microscopic charcoal
KW - SCP
Y1 - 2018
U6 - https://doi.org/10.1016/j.gloplacha.2018.07.010
SN - 0921-8181
SN - 1872-6364
VL - 169
SP - 188
EP - 201
PB - Elsevier
CY - Amsterdam
ER -
TY - GEN
A1 - Albers, Philip
A1 - Uestuen, Suayib
A1 - Witzel, Katja
A1 - Bornke, Frederik
T1 - Identification of a novel target of the bacterial effector HopZ1a
T2 - Phytopathology
N2 - The plant pathogen Pseudomonas syringae is a gram-negative bacterium which infects a wide range of plant species including important crops plants. To suppress plant immunity and cause disease P.syringae injects type-III effector proteins (T3Es) into the plant cell cytosol. In this study, we identified a novel target of the well characterized bacterial T3E HopZ1a. HopZ1a is an acetyltransferase that was shown to disrupt vesicle transport during innate immunity by acetylating tubulin. Using a yeast-two-hybrid screen approach, we identified a REMORIN (REM) protein from tobacco as a novel HopZ1a target. HopZ1a interacts with REM at the plasma membrane (PM) as shown by split-YFP experiments. Interestingly, we found that PBS1, a well-known kinase involved in plant immunity also interacts with REM in pull-down assays, and at the PM as shown by BiFC. Furthermore, we confirmed that REM is phosphorylated by PBS1 in vitro. Overexpression of REM provokes the upregulation of defense genes and leads to disease-like phenotypes pointing to a role of REM in plant immune signaling. Further protein-protein interaction studies reveal novel REM binding partners with a possible role in plant immune signaling. Thus, REM might act as an assembly hub for an immune signaling complex targeted by HopZ1a. Taken together, this is the first report describing that a REM protein is targeted by a bacterial effector. How HopZ1a might mechanistically manipulate the plant immune system through interfering with REM function will be discussed.
Y1 - 2018
SN - 0031-949X
SN - 1943-7684
VL - 108
IS - 10
PB - American Phytopathological Society
CY - Saint Paul
ER -
TY - THES
A1 - Kammel, Anne
T1 - Identifizierung früher epigenetischer Veränderungen, die zur Ausbildung einer Fettleber beitragen
Y1 - 2018
ER -
TY - JOUR
A1 - Grau, José Horacio
A1 - Hackl, Thomas
A1 - Koepfli, Klaus-Peter
A1 - Hofreiter, Michael
T1 - Improving draft genome contiguity with reference-derived in silico mate-pair libraries
JF - GigaScience
N2 - Background
Contiguous genome assemblies are a highly valued biological resource because of the higher number of completely annotated genes and genomic elements that are usable compared to fragmented draft genomes. Nonetheless, contiguity is difficult to obtain if only low coverage data and/or only distantly related reference genome assemblies are available.
Findings
In order to improve genome contiguity, we have developed Cross-Species Scaffolding—a new pipeline that imports long-range distance information directly into the de novo assembly process by constructing mate-pair libraries in silico.
Conclusions
We show how genome assembly metrics and gene prediction dramatically improve with our pipeline by assembling two primate genomes solely based on ∼30x coverage of shotgun sequencing data.
KW - genome assembly
KW - mate-pairs
KW - in silico
KW - scaffolding
KW - shotgun sequencing
Y1 - 2018
U6 - https://doi.org/10.1093/gigascience/giy029
SN - 2047-217X
VL - 7
IS - 5
SP - 1
EP - 6
PB - Oxford University Press
CY - Oxford
ER -
TY - JOUR
A1 - Maares, Maria
A1 - Keil, Claudia
A1 - Koza, Jenny
A1 - Straubing, Sophia
A1 - Schwerdtle, Tanja
A1 - Haase, Hajo
T1 - In Vitro Studies on Zinc Binding and Buffering by Intestinal Mucins
JF - International Journal of Molecular Sciences
N2 - The investigation of luminal factors influencing zinc availability and accessibility in the intestine is of great interest when analyzing parameters regulating intestinal zinc resorption. Of note, intestinal mucins were suggested to play a beneficial role in the luminal availability of zinc. Their exact zinc binding properties, however, remain unknown and the impact of these glycoproteins on human intestinal zinc resorption has not been investigated in detail. Thus, the aim of this study is to elucidate the impact of intestinal mucins on luminal uptake of zinc into enterocytes and its transfer into the blood. In the present study, in vitro zinc binding properties of mucins were analyzed using commercially available porcine mucins and secreted mucins of the goblet cell line HT-29-MTX. The molecular zinc binding capacity and average zinc binding affinity of these glycoproteins demonstrates that mucins contain multiple zinc-binding sites with biologically relevant affinity within one mucin molecule. Zinc uptake into the enterocyte cell line Caco-2 was impaired by zinc-depleted mucins. Yet this does not represent their form in the intestinal lumen in vivo under zinc adequate conditions. In fact, zinc-uptake studies into enterocytes in the presence of mucins with differing degree of zinc saturation revealed zinc buffering by these glycoproteins, indicating that mucin-bound zinc is still available for the cells. Finally, the impact of mucins on zinc resorption using three-dimensional cultures was studied comparing the zinc transfer of a Caco-2/HT-29-MTX co-culture and conventional Caco-2 monoculture. Here, the mucin secreting co-cultures yielded higher fractional zinc resorption and elevated zinc transport rates, suggesting that intestinal mucins facilitate the zinc uptake into enterocytes and act as a zinc delivery system for the intestinal epithelium.
KW - intestinal zinc resorption
KW - zinc binding
KW - mucus layer
KW - intestinal mucins
KW - in vitro intestinal model
KW - goblet cells
KW - Caco-2/HT-29-MTX-model
Y1 - 2018
U6 - https://doi.org/10.3390/ijms19092662
SN - 1422-0067
VL - 19
IS - 9
ER -
TY - JOUR
A1 - Uribe, Veronica
A1 - Ramadass, Radhan
A1 - Dogra, Deepika
A1 - Rasouli, S. Javad
A1 - Gunawan, Felix
A1 - Nakajima, Hiroyuki
A1 - Chiba, Ayano
A1 - Reischauer, Sven
A1 - Mochizuki, Naoki
A1 - Stainier, Didier Y. R.
T1 - In vivo analysis of cardiomyocyte proliferation during trabeculation
JF - Development : Company of Biologists
N2 - Cardiomyocyte proliferation is crucial for cardiac growth, patterning and regeneration; however, few studies have investigated the behavior of dividing cardiomyocytes in vivo. Here, we use time-lapse imaging of beating hearts in combination with the FUCCI system to monitor the behavior of proliferating cardiomyocytes in developing zebrafish. Confirming in vitro observations, sarcomere disassembly, as well as changes in cell shape and volume, precede cardiomyocyte cytokinesis. Notably, cardiomyocytes in zebrafish embryos and young larvae mostly divide parallel to the myocardial wall in both the compact and trabecular layers, and cardiomyocyte proliferation is more frequent in the trabecular layer. While analyzing known regulators of cardiomyocyte proliferation, we observed that the Nrg/ErbB2 and TGF beta signaling pathways differentially affect compact and trabecular layer cardiomyocytes, indicating that distinct mechanisms drive proliferation in these two layers. In summary, our data indicate that, in zebrafish, cardiomyocyte proliferation is essential for trabecular growth, but not initiation, and set the stage to further investigate the cellular and molecular mechanisms driving cardiomyocyte proliferation in vivo.
KW - Heart development
KW - Cardiomyocyte proliferation
KW - Trabeculation
KW - Sarcomere
Y1 - 2018
U6 - https://doi.org/10.1242/dev.164194
SN - 0950-1991
SN - 1477-9129
VL - 145
IS - 14
PB - Company biologists LTD
CY - Cambridge
ER -
TY - JOUR
A1 - Romero-Mujalli, Daniel
A1 - Jeltsch, Florian
A1 - Tiedemann, Ralph
T1 - Individual-based modeling of eco-evolutionary dynamics
BT - state of the art and future directions
JF - Regional environmental change
N2 - A challenge for eco-evolutionary research is to better understand the effect of climate and landscape changes on species and their distribution. Populations of species can respond to changes in their environment through local genetic adaptation or plasticity, dispersal, or local extinction. The individual-based modeling (IBM) approach has been repeatedly applied to assess organismic responses to environmental changes. IBMs simulate emerging adaptive behaviors from the basic entities upon which both ecological and evolutionary mechanisms act. The objective of this review is to summarize the state of the art of eco-evolutionary IBMs and to explore to what degree they already address the key responses of organisms to environmental change. In this, we identify promising approaches and potential knowledge gaps in the implementation of eco-evolutionary mechanisms to motivate future research. Using mainly the ISI Web of Science, we reveal that most of the progress in eco-evolutionary IBMs in the last decades was achieved for genetic adaptation to novel local environmental conditions. There is, however, not a single eco-evolutionary IBM addressing the three potential adaptive responses simultaneously. Additionally, IBMs implementing adaptive phenotypic plasticity are rare. Most commonly, plasticity was implemented as random noise or reaction norms. Our review further identifies a current lack of models where plasticity is an evolving trait. Future eco-evolutionary models should consider dispersal and plasticity as evolving traits with their associated costs and benefits. Such an integrated approach could help to identify conditions promoting population persistence depending on the life history strategy of organisms and the environment they experience.
KW - Modeling
KW - Individual-based models
KW - Ecology
KW - Evolution
KW - Eco-evolutionary dynamics
Y1 - 2018
U6 - https://doi.org/10.1007/s10113-018-1406-7
SN - 1436-3798
SN - 1436-378X
VL - 19
IS - 1
SP - 1
EP - 12
PB - Springer
CY - Heidelberg
ER -
TY - JOUR
A1 - van Velzen, Ellen
A1 - Thieser, Tamara
A1 - Berendonk, Thomas U.
A1 - Weitere, Markus
A1 - Gaedke, Ursula
T1 - Inducible defense destabilizes predator–prey dynamics
BT - the importance of multiple predators
JF - Oikos
N2 - Phenotypic plasticity in prey can have a dramatic impact on predator-prey dynamics, e.g. by inducible defense against temporally varying levels of predation. Previous work has overwhelmingly shown that this effect is stabilizing: inducible defenses dampen the amplitudes of population oscillations or eliminate them altogether. However, such studies have neglected scenarios where being protected against one predator increases vulnerability to another (incompatible defense). Here we develop a model for such a scenario, using two distinct prey phenotypes and two predator species. Each prey phenotype is defended against one of the predators, and vulnerable to the other. In strong contrast with previous studies on the dynamic effects of plasticity involving a single predator, we find that increasing the level of plasticity consistently destabilizes the system, as measured by the amplitude of oscillations and the coefficients of variation of both total prey and total predator biomasses. We explain this unexpected and seemingly counterintuitive result by showing that plasticity causes synchronization between the two prey phenotypes (and, through this, between the predators), thus increasing the temporal variability in biomass dynamics. These results challenge the common view that plasticity should always have a stabilizing effect on biomass dynamics: adding a single predator-prey interaction to an established model structure gives rise to a system where different mechanisms may be at play, leading to dramatically different outcomes.
KW - phenotypic plasticity
KW - inducible defense
KW - stability
KW - synchronization
KW - predator-prey dynamics
Y1 - 2018
U6 - https://doi.org/10.1111/oik.04868
SN - 0030-1299
SN - 1600-0706
VL - 127
IS - 11
SP - 1551
EP - 1562
PB - Wiley
CY - Hoboken
ER -
TY - JOUR
A1 - Oprzeska-Zingrebe, Ewa Anna
A1 - Meyer, Susann
A1 - Roloff, Alexander
A1 - Kunte, Hans-Jörg
A1 - Smiatek, Jens
T1 - Influence of compatible solute ectoine on distinct DNA structures
BT - thermodynamic insights into molecular binding mechanisms and destabilization effects
JF - Physical chemistry, chemical physics : a journal of European Chemical Societies
N2 - In nature, the cellular environment of DNA includes not only water and ions, but also other components and co-solutes, which can exert both stabilizing and destabilizing effects on particular oligonucleotide conformations. Among them, ectoine, known as an important osmoprotectant organic co-solute in a broad range of pharmaceutical products, turns out to be of particular relevance. In this article, we study the influence of ectoine on a short single-stranded DNA fragment and on double-stranded helical B-DNA in aqueous solution by means of atomistic molecular dynamics (MD) simulations in combination with molecular theories of solution. Our results demonstrate a conformation-dependent binding behavior of ectoine, which favors the unfolded state of DNA by a combination of electrostatic and dispersion interactions. In conjunction with the Kirkwood-Buff theory, we introduce a simple framework to compute the influence of ectoine on the DNA melting temperature. Our findings reveal a significant linear decrease of the melting temperature with increasing ectoine concentration, which is found to be in qualitative agreement with results from denaturation experiments. The outcomes of our computer simulations provide a detailed mechanistic rationale for the surprising destabilizing influence of ectoine on distinct DNA structures.
Y1 - 2018
U6 - https://doi.org/10.1039/c8cp03543a
SN - 1463-9076
SN - 1463-9084
VL - 20
IS - 40
SP - 25861
EP - 25874
PB - Royal Society of Chemistry
CY - Cambridge
ER -
TY - THES
A1 - Al Fadel, Frdoos
T1 - Influence of sphingosine 1-phosphate and its receptor modulators on the development of liver fibrosis
Y1 - 2018
ER -
TY - JOUR
A1 - Rodriguez Cubillos, Andres Eduardo
A1 - Tong, Hao
A1 - Alseekh, Saleh
A1 - de Abreu e Lima, Francisco Anastacio
A1 - Yu, Jing
A1 - Fernie, Alisdair
A1 - Nikoloski, Zoran
A1 - Laitinen, Roosa A. E.
T1 - Inheritance patterns in metabolism and growth in diallel crosses of Arabidopsis thaliana from a single growth habitat
JF - Heredity
N2 - Metabolism is a key determinant of plant growth and modulates plant adaptive responses. Increased metabolic variation due to heterozygosity may be beneficial for highly homozygous plants if their progeny is to respond to sudden changes in the habitat. Here, we investigate the extent to which heterozygosity contributes to the variation in metabolism and size of hybrids of Arabidopsis thaliana whose parents are from a single growth habitat. We created full diallel crosses among seven parents, originating from Southern Germany, and analysed the inheritance patterns in primary and secondary metabolism as well as in rosette size in situ. In comparison to primary metabolites, compounds from secondary metabolism were more variable and showed more pronounced non-additive inheritance patterns which could be attributed to epistasis. In addition, we showed that glucosinolates, among other secondary metabolites, were positively correlated with a proxy for plant size. Therefore, our study demonstrates that heterozygosity in local A. thaliana population generates metabolic variation and may impact several tasks directly linked to metabolism.
Y1 - 2018
U6 - https://doi.org/10.1038/s41437-017-0030-5
SN - 0018-067X
SN - 1365-2540
VL - 120
IS - 5
SP - 463
EP - 473
PB - Nature Publ. Group
CY - London
ER -
TY - JOUR
A1 - Scheunemann, Michael
A1 - Brady, Siobhan M.
A1 - Nikoloski, Zoran
T1 - Integration of large-scale data for extraction of integrated Arabidopsis root cell-type specific models
JF - Scientific reports
N2 - Plant organs consist of multiple cell types that do not operate in isolation, but communicate with each other to maintain proper functions. Here, we extract models specific to three developmental stages of eight root cell types or tissue layers in Arabidopsis thaliana based on a state-of-the-art constraint-based modeling approach with all publicly available transcriptomics and metabolomics data from this system to date. We integrate these models into a multi-cell root model which we investigate with respect to network structure, distribution of fluxes, and concordance to transcriptomics and proteomics data. From a methodological point, we show that the coupling of tissue-specific models in a multi-tissue model yields a higher specificity of the interconnected models with respect to network structure and flux distributions. We use the extracted models to predict and investigate the flux of the growth hormone indole-3-actetate and its antagonist, trans-Zeatin, through the root. While some of predictions are in line with experimental evidence, constraints other than those coming from the metabolic level may be necessary to replicate the flow of indole-3-actetate from other simulation studies. Therefore, our work provides the means for data-driven multi-tissue metabolic model extraction of other Arabidopsis organs in the constraint-based modeling framework.
Y1 - 2018
U6 - https://doi.org/10.1038/s41598-018-26232-8
SN - 2045-2322
VL - 8
PB - Nature Publ. Group
CY - London
ER -
TY - JOUR
A1 - Wuster, Wolfgang
A1 - Chirio, Laurent
A1 - Trape, Jean-Francois
A1 - Ineich, Ivan
A1 - Jackson, Kate
A1 - Greenbaum, Eli
A1 - Barron, Cesar
A1 - Kusamba, Chifundera
A1 - Nagy, Zoltan T.
A1 - Storey, Richard
A1 - Hall, Cara
A1 - Wuster, Catharine E.
A1 - Barlow, Axel
A1 - Broadley, Donald G.
T1 - Integration of nuclear and mitochondrial gene sequences and morphology reveals unexpected diversity in the forest cobra (Naja melanoleuca) species complex in Central and West Africa (Serpentes: Elapidae)
JF - Zootaxa : an international journal of zootaxonomy ; a rapid international journal for animal taxonomists
N2 - Cobras are among the most widely known venomous snakes, and yet their taxonomy remains incompletely understood, particularly in Africa. Here, we use a combination of mitochondrial and nuclear gene sequences and morphological data to diagnose species limits within the African forest cobra, Naja (Boulengerina) melanoleuca. Mitochondrial DNA sequences reveal deep divergences within this taxon. Congruent patterns of variation in mtDNA, nuclear genes and morphology support the recognition of five separate species, confirming the species status of N. subfulva and N. peroescobari, and revealing two previously unnamed West African species, which are described as new: Naja (Boulengerina) guineensis sp. nov. Broadley, Trape, Chirio, Ineich & Wuster, from the Upper Guinea forest of West Africa, and Naja (Boulengerina) savannula sp. nov. Broadley, Trape, Chirio & Wuster, a banded form from the savanna-forest mosaic of the Guinea and Sudanian savannas of West Africa. The discovery of cryptic diversity in this iconic group highlights our limited understanding of tropical African biodiversity, hindering our ability to conserve it effectively.
KW - Integrative taxonomy
KW - Africa
KW - Naja melanoleuca
KW - Naja guineensis sp nov.
KW - Naja savannula sp nov.
KW - Elapidae
KW - systematics
Y1 - 2018
U6 - https://doi.org/10.11646/zootaxa.4455.1.3
SN - 1175-5326
SN - 1175-5334
VL - 4455
IS - 1
SP - 68
EP - 98
PB - Magnolia Press
CY - Auckland
ER -
TY - JOUR
A1 - Crawford, Michael
A1 - Jeltsch, Florian
A1 - May, Felix
A1 - Grimm, Volker
A1 - Schlägel, Ulrike E.
T1 - Intraspecific trait variation increases species diversity in a trait-based grassland model
JF - Oikos
N2 - Intraspecific trait variation (ITV) is thought to play a significant role in community assembly, but the magnitude and direction of its influence are not well understood. Although it may be critical to better explain population persistence, species interactions, and therefore biodiversity patterns, manipulating ITV in experiments is challenging. We therefore incorporated ITV into a trait‐ and individual‐based model of grassland community assembly by adding variation to the plants’ functional traits, which then drive life‐history tradeoffs. Varying the amount of ITV in the simulation, we examine its influence on pairwise‐coexistence and then on the species diversity in communities of different initial sizes. We find that ITV increases the ability of the weakest species to invade most, but that this effect does not scale to the community level, where the primary effect of ITV is to increase the persistence and abundance of the competitively‐average species. Diversity of the initial community is also of critical importance in determining ITV's efficacy; above a threshold of interspecific diversity, ITV does not increase diversity further. For communities below this threshold, ITV mainly helps to increase diversity in those communities that would otherwise be low‐diversity. These findings suggest that ITV actively maintains diversity by helping the species on the margins of persistence, but mostly in habitats of relatively low alpha and beta diversity.
KW - community assembly
KW - individual-based model
KW - intraspecific trait variation
Y1 - 2018
U6 - https://doi.org/10.1111/oik.05567
SN - 0030-1299
SN - 1600-0706
VL - 128
IS - 3
SP - 441
EP - 455
PB - Wiley
CY - Hoboken
ER -
TY - JOUR
A1 - Yan, Wan
A1 - Fang, Liang
A1 - Nöchel, Ulrich
A1 - Gould, Oliver E. C.
A1 - Behl, Marc
A1 - Kratz, Karl
A1 - Lendlein, Andreas
T1 - Investigating the roles of crystallizable and glassy switching segments within multiblock copolymer shape-memory materials
JF - MRS Advances
N2 - The variation of the molecular architecture of multiblock copolymers has enabled the introduction of functional behaviour and the control of key mechanical properties. In the current study, we explore the synergistic relationship of two structural components in a shape-memory material formed of a multiblock copolymer with crystallizable poly(epsilon-caprolactone) and crystallizable polyfoligo(3S-iso-butylmorpholine-2,5-dione) segments (PCL-PIBMD). The thermal and structural properties of PCL-PIBMD films were compared with PCI.-PU and PMMD-PU investigated by means of DSC, SAXS and WARS measurements. The shape-memory properties were quantified by cyclic, thermomechanical tensile tests, where deformation strains up to 900% were applied for programming PCL-PIBMD films at 50 degrees C. Toluene vapor treatment experiments demonstrated that the temporary shape was fixed mainly by glassy PIBMD domains at strains lower than 600% with the PCL contribution to fixation increasing to 42 +/- 2% at programming strains of 900% This study into the shape-memory mechanism of PCL-PIBMD provides insight into the structure function relation in multiblock copolymers with both crystallizable and glassy switching segments.
Y1 - 2018
U6 - https://doi.org/10.1557/adv.2018.590
SN - 2059-8521
VL - 3
IS - 63
SP - 3741
EP - 3749
PB - Cambridge Univ. Press
CY - New York
ER -
TY - JOUR
A1 - Abbas, Ioana M.
A1 - Vranic, Marija
A1 - Hoffmann, Holger
A1 - El-Khatib, Ahmed H.
A1 - Montes-Bayón, María
A1 - Möller, Heiko Michael
A1 - Weller, Michael G.
T1 - Investigations of the Copper Peptide Hepcidin-25 by
LC-MS/MS and NMR⁺
JF - International Journal of Molecular Sciences
N2 - Hepcidin-25 was identified as themain iron regulator in the human body, and it by binds to the sole iron-exporter ferroportin. Studies showed that the N-terminus of hepcidin is responsible for this interaction, the same N-terminus that encompasses a small copper(II) binding site known as the ATCUN (amino-terminal Cu(II)- and Ni(II)-binding) motif. Interestingly, this copper-binding property is largely ignored in most papers dealing with hepcidin-25. In this context, detailed investigations of the complex formed between hepcidin-25 and copper could reveal insight into its biological role. The present work focuses on metal-bound hepcidin-25 that can be considered the biologically active form. The first part is devoted to the reversed-phase chromatographic separation of copper-bound and copper-free hepcidin-25 achieved by applying basic mobile phases containing 0.1% ammonia. Further, mass spectrometry (tandemmass spectrometry (MS/MS), high-resolutionmass spectrometry (HRMS)) and nuclear magnetic resonance (NMR) spectroscopy were employed to characterize the copper-peptide. Lastly, a three-dimensional (3D)model of hepcidin-25with bound copper(II) is presented. The identification of metal complexes and potential isoforms and isomers, from which the latter usually are left undetected by mass spectrometry, led to the conclusion that complementary analytical methods are needed to characterize a peptide calibrant or referencematerial comprehensively. Quantitative nuclear magnetic resonance (qNMR), inductively-coupled plasma mass spectrometry (ICP-MS), ion-mobility spectrometry (IMS) and chiral amino acid analysis (AAA) should be considered among others.
KW - hepcidin-25
KW - copper
KW - nickel
KW - copper complex
KW - ATCUN motif
KW - metal complex
KW - MS
KW - NMR structure
KW - metal peptide
KW - metalloprotein
KW - metallopeptide
KW - isomerization
KW - racemization
KW - purity
KW - reference material
Y1 - 2018
U6 - https://doi.org/10.3390/ijms19082271
SN - 1422-0067
SN - 1661-6596
VL - 19
IS - 8
PB - Molecular Diversity Preservation International
CY - Basel
ER -
TY - JOUR
A1 - Burschel, Sabrina
A1 - Decovic, Doris Kreuzer
A1 - Nuber, Franziska
A1 - Stiller, Marie
A1 - Hofmann, Maud
A1 - Zupok, Arkadiusz
A1 - Siemiatkowska, Beata
A1 - Gorka, Michal Jakub
A1 - Leimkühler, Silke
A1 - Friedrich, Thorsten
T1 - Iron-sulfur cluster carrier proteins involved in the assembly of Escherichia coli NADH
BT - ubiquinone oxidoreductase (complex I)
JF - Molecular microbiology
N2 - The NADH:ubiquinone oxidoreductase (respiratory complex I) is the main entry point for electrons into the Escherichia coli aerobic respiratory chain. With its sophisticated setup of 13 different subunits and 10 cofactors, it is anticipated that various chaperones are needed for its proper maturation. However, very little is known about the assembly of E. coli complex I, especially concerning the incorporation of the iron-sulfur clusters. To identify iron-sulfur cluster carrier proteins possibly involved in the process, we generated knockout strains of NfuA, BolA, YajL, Mrp, GrxD and IbaG that have been reported either to be involved in the maturation of mitochondrial complex I or to exert influence on the clusters of bacterial complex. We determined the NADH and succinate oxidase activities of membranes from the mutant strains to monitor the specificity of the individual mutations for complex I. The deletion of NfuA, BolA and Mrp led to a decreased stability and partially disturbed assembly of the complex as determined by sucrose gradient centrifugation and native PAGE. EPR spectroscopy of cytoplasmic membranes revealed that the BolA deletion results in the loss of the binuclear Fe/S cluster N1b.
Y1 - 2018
U6 - https://doi.org/10.1111/mmi.14137
SN - 0950-382X
SN - 1365-2958
VL - 111
IS - 1
SP - 31
EP - 45
PB - Wiley
CY - Hoboken
ER -
TY - GEN
A1 - Higgs, Eric S.
A1 - Harris, Jim A.
A1 - Heger, Tina
A1 - Hobbs, Richard J.
A1 - Murphy, Stephen D.
A1 - Suding, Katharine N.
T1 - Keep ecological restoration open and flexible
T2 - Nature Ecology & Evolution
Y1 - 2018
U6 - https://doi.org/10.1038/s41559-018-0483-9
SN - 2397-334X
VL - 2
IS - 4
SP - 580
EP - 580
PB - Nature Publ. Group
CY - London
ER -
TY - JOUR
A1 - Hochrein, Lena
A1 - Mitchell, Leslie A.
A1 - Schulz, Karina
A1 - Messerschmidt, Katrin
A1 - Müller-Röber, Bernd
T1 - L-SCRaMbLE as a tool for light-controlled Cre-mediated recombination in yeast
JF - Nature Communications
N2 - The synthetic yeast genome constructed by the International Synthetic Yeast Sc2.0 consortium adds thousands of loxPsym recombination sites to all 16 redesigned chromosomes, allowing the shuffling of Sc2.0 chromosome parts by the Cre-loxP recombination system thereby enabling genome evolution experiments. Here, we present L-SCRaMbLE, a lightcontrolled Cre recombinase for use in the yeast Saccharomyces cerevisiae. L-SCRaMbLE allows tight regulation of recombinase activity with up to 179-fold induction upon exposure to red light. The extent of recombination depends on induction time and concentration of the chromophore phycocyanobilin (PCB), which can be easily adjusted. The tool presented here provides improved recombination control over the previously reported estradiol-dependent SCRaMbLE induction system, mediating a larger variety of possible recombination events in SCRaMbLE-ing a reporter plasmid. Thereby, L-SCRaMbLE boosts the potential for further customization and provides a facile application for use in the S. cerevisiae genome reengineering project Sc2.0 or in other recombination-based systems.
Y1 - 2018
U6 - https://doi.org/10.1038/s41467-017-02208-6
SN - 2041-1723
VL - 9
PB - Nature Publ. Group
CY - London
ER -
TY - JOUR
A1 - Schirrmeister, Lutz
A1 - Bobrov, Anatoly
A1 - Raschke, Elena
A1 - Herzschuh, Ulrike
A1 - Strauss, Jens
A1 - Pestryakova, Luidmila Agafyevna
A1 - Wetterich, Sebastian
T1 - Late Holocene ice-wedge polygon dynamics in northeastern Siberian coastal lowlands
JF - Arctic, antarctic, and alpine research : an interdisciplinary journal
N2 - Ice-wedge polygons are common features of northeastern Siberian lowland periglacial tundra landscapes. To deduce the formation and alternation of ice-wedge polygons in the Kolyma Delta and in the Indigirka Lowland, we studied shallow cores, up to 1.3 m deep, from polygon center and rim locations. The formation of well-developed low-center polygons with elevated rims and wet centers is shown by the beginning of peat accumulation, increased organic matter contents, and changes in vegetation cover from Poaceae-, Alnus-, and Betula-dominated pollen spectra to dominating Cyperaceae and Botryoccocus presence, and Carex and Drepanocladus revolvens macro-fossils. Tecamoebae data support such a change from wetland to open-water conditions in polygon centers by changes from dominating eurybiontic and sphagnobiontic to hydrobiontic species assemblages. The peat accumulation indicates low-center polygon formation and started between 2380 +/- 30 and 1676 +/- 32 years before present (BP) in the Kolyma Delta. We recorded an opposite change from open-water to wetland conditions because of rim degradation and consecutive high-center polygon formation in the Indigirka Lowland between 2144 +/- 33 and 1632 +/- 32 years BP. The late Holocene records of polygon landscape development reveal changes in local hydrology and soil moisture.
KW - Permafrost
KW - cryolithology
KW - radiocarbon dating
KW - paleoecology
KW - rhizopods
KW - pollen
KW - plant macro-fossils
Y1 - 2018
U6 - https://doi.org/10.1080/15230430.2018.1462595
SN - 1523-0430
SN - 1938-4246
VL - 50
IS - 1
PB - Institute of Arctic and Alpine Research, University of Colorado
CY - Boulder
ER -
TY - JOUR
A1 - Mittler, Udo
A1 - Blasius, Bernd
A1 - Gaedke, Ursula
A1 - Ryabov, Alexey B.
T1 - Length-volume relationship of lake phytoplankton
JF - Limnology and Oceanography: Methods
N2 - The shapes of phytoplankton units (unicellular organisms and colonies) are extremely diverse, and no unique relationship exists between their volume, V, and longest linear dimension, L. However, an approximate scaling between these parameters can be found because the shape variations within each size class are constrained by cell physiology, grazing pressure, and optimality of resource acquisition. To determine this scaling and to test for its seasonal and interannual variation under changing environmental conditions, we performed weighted regression analysis of time-dependent length-volume relations of the phytoplankton community in large deep Lake Constance from 1979 to 1999. We show that despite a large variability in species composition, the V(L) relationship can be approximated as a power law, V similar to L-alpha, with a scaling exponent alpha = 3 for small cells (L < 25 mu m) and alpha = 1.7 if the fitting is performed over the entire length range, including individual cells and colonies. The best description is provided by a transitional power function describing a regime change from a scaling exponent of 3 for small cells to an exponent of 0.4 in the range of large phytoplankton. Testing different weighted fitting approaches we show that remarkably the best prediction of the total community biovolume from measurements of L and cell density is obtained when the regression is weighted with the squares of species abundances. Our approach should also be applicable to other systems and allows converting phytoplankton length distributions (e.g., obtained with automatic monitoring such as flow cytometry) into distributions of biovolume and biovolume-related phytoplankton traits.
Y1 - 2018
U6 - https://doi.org/10.1002/lom3.10296
SN - 1541-5856
VL - 17
IS - 1
SP - 58
EP - 68
PB - Wiley
CY - Hoboken
ER -
TY - JOUR
A1 - Fischer, Stefan
A1 - Mayer-Scholl, Anne
A1 - Imholt, Christian
A1 - Spierling, Nastasja G.
A1 - Heuser, Elisa
A1 - Schmidt, Sabrina
A1 - Reil, Daniela
A1 - Rosenfeld, Ulrike
A1 - Jacob, Jens
A1 - Nöckler, Karsten
A1 - Ulrich, Rainer G.
T1 - Leptospira genomospecies and sequence type prevalence in small mammal populations in Germany
JF - Vector-Borne and Zoonotic Diseases
N2 - Leptospirosis is a worldwide emerging infectious disease caused by zoonotic bacteria of the genus Leptospira. Numerous mammals, including domestic and companion animals, can be infected by Leptospira spp., but rodents and other small mammals are considered the main reservoir. The annual number of recorded human leptospirosis cases in Germany (2001-2016) was 25-166. Field fever outbreaks in strawberry pickers, due to infection with Leptospira kirschneri serovar Grippotyphosa, were reported in 2007 and 2014. To identify the most commonly occurring Leptospira genomospecies, sequence types (STs), and their small mammal host specificity, a monitoring study was performed during 2010-2014 in four federal states of Germany. Initial screening of kidney tissues of 3,950 animals by PCR targeting the lipl32 gene revealed 435 rodents of 6 species and 89 shrews of three species positive for leptospiral DNA. PCR-based analyses resulted in the identification of the genomospecies L. kirschneri (62.7%), Leptospira interrogans (28.3%), and Leptospira borgpetersenii (9.0%), which are represented by four, one, and two STs, respectively. The average Leptospira prevalence was highest (approximate to 30%) in common voles (Microtus arvalis) and field voles (Microtus agrestis). Both species were exclusively infected with L. kirschneri. In contrast, in bank voles (Myodes glareolus) and yellow-necked mice (Apodemus flavicollis), DNA of all three genomospecies was detected, and in common shrews (Sorex araneus) DNA of L. kirschneri and L. borgpetersenii was identified. The association between individual infection status and demographic factors varied between species; infection status was always positively correlated to body weight. In conclusion, the study confirmed a broad geographical distribution of Leptospira in small mammals and suggested an important public health relevance of common and field voles as reservoirs of L. kirschneri. Furthermore, the investigations identified seasonal, habitat-related, as well as individual influences on Leptospira prevalence in small mammals that might impact public health.
KW - demography
KW - Germany
KW - habitat
KW - Leptospira spp
KW - leptospirosis
KW - MLST
KW - rodent
KW - shrew
KW - SLST
Y1 - 2018
U6 - https://doi.org/10.1089/vbz.2017.2140
SN - 1530-3667
SN - 1557-7759
VL - 18
IS - 4
SP - 188
EP - 199
PB - Liebert
CY - New Rochelle
ER -
TY - JOUR
A1 - Hoffmann, Julia
A1 - Palme, Rupert
A1 - Eccard, Jana
T1 - Long-term dim light during nighttime changes activity patterns and space use in experimental small mammal populations
JF - Environmental pollution
N2 - Artificial light at night (ALAN) is spreading worldwide and thereby is increasingly interfering with natural dark-light cycles. Meanwhile, effects of very low intensities of light pollution on animals have rarely been investigated. We explored the effects of low intensity ALAN over seven months in eight experimental bank vole (Myodes glareolus) populations in large grassland enclosures over winter and early breeding season, using LED garden lamps. initial populations consisted of eight individuals (32 animals per hectare) in enclosures with or without ALAN. We found that bank voles under ALAN experienced changes in daily activity patterns and space use behavior, measured by automated radio telemetry. There were no differences in survival and body mass, measured with live trapping, and none in levels of fecal glucocorticoid metabolites. Voles in the ALAN treatment showed higher activity at night during half moon, and had larger day ranges during new moon. Thus, even low levels of light pollution as experienced in remote areas or by sky glow can lead to changes in animal behavior and could have consequences for species interactions. (C) 2018 Elsevier Ltd. All rights reserved.
KW - Myodes glareolus
KW - Light pollution
KW - Chronic stress
KW - Survival success
KW - Artificial light
KW - LED
Y1 - 2018
U6 - https://doi.org/10.1016/j.envpol.2018.03.107
SN - 0269-7491
SN - 1873-6424
VL - 238
SP - 844
EP - 851
PB - Elsevier
CY - Oxford
ER -
TY - JOUR
A1 - Scherer, Ulrike
A1 - Tiedemann, Ralph
A1 - Schlupp, Ingo
T1 - Male size, not female preferences influence female reproductive success in a poeciliid fish (Poecilia latipinna)
BT - a combined behavioural/genetic approach
JF - BMC Research Notes
N2 - Objective
We investigated the potential role of indirect benefits for female mate preferences in a highly promiscuous species of live-bearing fishes, the sailfin molly Poecilia latipinna using an integrative approach that combines methods from animal behavior, life-history evolution, and genetics. Males of this species solely contribute sperm for reproduction, and consequently females do not receive any direct benefits. Despite this, females typically show clear mate preferences. It has been suggested that females can increase their reproductive success through indirect benefits from choosing males of higher quality.
Results
Although preferences for large body size have been recorded as an honest signal for genetic quality, this particular study resulted in female preference being unaffected by male body size. Nonetheless, larger males did sire more offspring, but with no effect on offspring quality. This study presents a methodical innovation by combining preference testing with life history measurements—such as the determination of the dry weight of fish embryos—and paternity analyses on single fish embryos.
KW - Fitness
KW - Life history
KW - Mate choice
KW - Microsatellite analysis
KW - Offspring weight
KW - Paternity analysis
KW - Sailfin molly
KW - Sexual selection
Y1 - 2018
U6 - https://doi.org/10.1186/s13104-018-3487-2
SN - 1756-0500
VL - 11
IS - 364
SP - 1
EP - 5
PB - Biomed Central
CY - London
ER -
TY - JOUR
A1 - Chen, Pan
A1 - Bornhorst, Julia
A1 - Aschner, Michael
T1 - Manganese metabolism in humans
JF - Frontiers in Bioscience-Landmark
N2 - Manganese (Mn) is an essential nutrient for intracellular activities; it functions as a cofactor for a variety of enzymes, including arginase, glutamine synthetase (GS), pyruvate carboxylase and Mn superoxide dismutase (Mn-SOD). Through these metalloproteins, Mn plays critically important roles in development, digestion, reproduction, antioxidant defense, energy production, immune response and regulation of neuronal activities. Mn deficiency is rare. In contrast Mn poisoning may be encountered upon overexposure to this metal. Excessive Mn tends to accumulate in the liver, pancreas, bone, kidney and brain, with the latter being the major target of Mn intoxication. Hepatic cirrhosis, polycythemia, hypermanganesemia, dystonia and Parkinsonism-like symptoms have been reported in patients with Mn poisoning. In recent years, Mn has come to the forefront of environmental concerns due to its neurotoxicity. Molecular mechanisms of Mn toxicity include oxidative stress, mitochondrial dysfunction, protein misfolding, endoplasmic reticulum (ER) stress, autophagy dysregulation, apoptosis, and disruption of other metal homeostasis. The mechanisms of Mn homeostasis are not fully understood. Here, we will address recent progress in Mn absorption, distribution and elimination across different tissues, as well as the intracellular regulation of Mn homeostasis in cells. We will conclude with recommendations for future research areas on Mn metabolism.
KW - Manganese
KW - Metal Metabolism
KW - Homeostasis
KW - Blood-Brain Barrier
KW - Neurotoxicity
KW - Transporters
KW - Review
Y1 - 2018
U6 - https://doi.org/10.2741/4665
SN - 1093-9946
SN - 1093-4715
VL - 23
IS - 9
SP - 1655
EP - 1679
PB - Frontiers in Bioscience INC
CY - Irvine
ER -
TY - JOUR
A1 - Fritz, Michael Andre
A1 - Rosa, Stefanie
A1 - Sicard, Adrien
T1 - Mechanisms Underlying the Environmentally Induced Plasticity of Leaf Morphology
JF - Frontiers in genetics
N2 - The primary function of leaves is to provide an interface between plants and their environment for gas exchange, light exposure and thermoregulation. Leaves have, therefore a central contribution to plant fitness by allowing an efficient absorption of sunlight energy through photosynthesis to ensure an optimal growth. Their final geometry will result from a balance between the need to maximize energy uptake while minimizing the damage caused by environmental stresses. This intimate relationship between leaf and its surroundings has led to an enormous diversification in leaf forms. Leaf shape varies between species, populations, individuals or even within identical genotypes when those are subjected to different environmental conditions. For instance, the extent of leaf margin dissection has, for long, been found to inversely correlate with the mean annual temperature, such that Paleobotanists have used models based on leaf shape to predict the paleoclimate from fossil flora. Leaf growth is not only dependent on temperature but is also regulated by many other environmental factors such as light quality and intensity or ambient humidity. This raises the question of how the different signals can be integrated at the molecular level and converted into clear developmental decisions. Several recent studies have started to shed the light on the molecular mechanisms that connect the environmental sensing with organ-growth and patterning. In this review, we discuss the current knowledge on the influence of different environmental signals on leaf size and shape, their integration as well as their importance for plant adaptation.
KW - plants
KW - leaf morphology
KW - environment
KW - developmental plasticity
KW - gene regulatory networks
KW - sensory system
KW - gene responsiveness
Y1 - 2018
U6 - https://doi.org/10.3389/fgene.2018.00478
SN - 1664-8021
VL - 9
PB - Frontiers Research Foundation
CY - Lausanne
ER -
TY - JOUR
A1 - Koziel, Slawomir
A1 - Scheffler, Christiane
A1 - Tutkuviene, Janina
A1 - Jakimaviciene, Egle Marija
A1 - Mumm, Rebekka
A1 - Barbieri, Davide
A1 - Godina, Elena
A1 - El-Shabrawi, Mortada
A1 - Elhusseini, Mona
A1 - Musalek, Martin
A1 - Pruszkowska-Przybylska, Paulina
A1 - El Dash, Hanaa H.
A1 - Safar, Hebatalla Hassan
A1 - Lehmann, Andreas
A1 - Swanson, James
A1 - Bogin, Barry
A1 - Liu, Yuk-Chien
A1 - Groth, Detlef
A1 - Kirchengast, Sylvia
A1 - Siniarska, Anna
A1 - Nieczuja-Dwojacka, Joanna
A1 - Kralik, Miroslav
A1 - Satake, Takashi
A1 - Harc, Tomasz
A1 - Roelants, Mathieu
A1 - Hermanussen, Michael
T1 - Meeting Report: Growth and social environment
BT - Proceedings of the 25th Aschauer Soiree, held at Krobielowice, Poland, November 18th 2017
JF - Pediatric Endocrinology Reviews
N2 - Twenty-two scientists met at Krobielowice, Poland, to discuss the impact of the social environment, spatial proximity, migration, poverty, but also psychological factors such as body perception and satisfaction, and social stressors such as elite sports, and teenage pregnancies, on child and adolescent growth. The data analysis included linear mixed effects models with different random effects, Monte Carlo analyses, and network simulations. The work stressed the importance of the peer group, but also included historic material, some considerations about body proportions, and growth in chronic liver, and congenital heart disease.
KW - Body height
KW - Social environment
KW - Strategic growth adjustment
KW - Competitive growth
KW - Community effects on growth
Y1 - 2018
U6 - https://doi.org/10.17458/per.vol15.2018.ksh.mr.GrowthSocialEnvironment
SN - 1565-4753
VL - 15
IS - 4
SP - 319
EP - 329
PB - Medical Media
CY - Netanya
ER -
TY - JOUR
A1 - Knoblauch, Christian
A1 - Beer, Christian
A1 - Liebner, Susanne
A1 - Grigoriev, Mikhail N.
A1 - Pfeiffer, Eva-Maria
T1 - Methane production as key to the greenhouse gas budget of thawing permafrost
JF - Nature climate change
N2 - Permafrost thaw liberates frozen organic carbon, which is decomposed into carbon dioxide (CO2) and methane (CH4). The release of these greenhouse gases (GHGs) forms a positive feedback to atmospheric CO2 and CH4 concentrations and accelerates climate change(1,2). Current studies report a minor importance of CH4 production in water-saturated (anoxic) permafrost soils(3-6) and a stronger permafrost carbon-climate feedback from drained (oxic) soils(1,7). Here we show through seven-year laboratory incubations that equal amounts of CO2 and CH4 are formed in thawing permafrost under anoxic conditions after stable CH4-producing microbial communities have established. Less permafrost carbon was mineralized under anoxic conditions but more CO2-carbon equivalents (CO2Ce) were formed than under oxic conditions when the higher global warming potential (GWP) of CH4 is taken into account(8). A model of organic carbon decomposition, calibrated with the observed decomposition data, predicts a higher loss of permafrost carbon under oxic conditions (113 +/- 58 g CO2-C kgC(-1) (kgC, kilograms of carbon)) by 2100, but a twice as high production of CO2-Ce (241 +/- 138 g CO2-Ce kgC(-1)) under anoxic conditions. These findings challenge the view of a stronger permafrost carbon-climate feedback from drained soils1,7 and emphasize the importance of CH4 production in thawing permafrost on climate-relevant timescales.
Y1 - 2018
U6 - https://doi.org/10.1038/s41558-018-0095-z
SN - 1758-678X
SN - 1758-6798
VL - 8
IS - 4
SP - 309
EP - 312
PB - Nature Publ. Group
CY - London
ER -
TY - JOUR
A1 - Batista, A. M. M.
A1 - Woodhouse, Jason Nicholas
A1 - Grossart, Hans-Peter
A1 - Giani, A.
T1 - Methanogenic archaea associated to Microcystis sp. in field samples and in culture
JF - Hydrobiologia : acta hydrobiologica, hydrographica, limnologica et protistologica
N2 - Cyanobacterial mass developments impact the community composition of heterotrophic microorganisms with far-reaching consequences for biogeochemical and energy cycles of freshwater ecosystems including reservoirs. Here we sought to evaluate the temporal stability of methanogenic archaea in the water column and further scrutinize their associations with cyanobacteria. Monthly samples were collected from October 2009 to December 2010 in hypereutrophic Pampulha reservoir with permanently blooming cyanobacteria, and from January to December 2011 in oligotrophic Volta Grande reservoir with only sporadic cyanobacteria incidence. The presence of archaea in cyanobacterial cultures was investigated by screening numerous strains of Microcystis spp. from these reservoirs as well as from lakes in Europe, Asia, and North-America. We consistently determined the occurrence of archaea, in particular methanogenic archaea, in both reservoirs throughout the year. However, archaea were only associated with two strains (Microcystis sp. UFMG 165 and UFMG 175) recently isolated from these reservoirs. These findings do not implicate archaea in the occurrence of methane in the epilimnion of inland waters, but rather serve to highlight the potential of microhabitats associated with particles, including phytoplankton, to shelter unique microbial communities.
KW - Cyanobacteria
KW - Methanogenic archaea
KW - Bacterial community composition
KW - Microcystis sp
KW - Tropical reservoir
Y1 - 2018
U6 - https://doi.org/10.1007/s10750-018-3655-3
SN - 0018-8158
SN - 1573-5117
VL - 831
IS - 1
SP - 163
EP - 172
PB - Springer
CY - Dordrecht
ER -
TY - THES
A1 - Bolius, Sarah
T1 - Microbial invasions in aquatic systems – strain identity, genetic diversity and timing
N2 - Biological invasions are the dispersal and following establishment of species outside their native habitat. Due to globalisation, connectivity of regions and climate changes the number of invasive species and their successful establishment is rising. The impact of these species is mostly negative, can induce community and habitat alterations, and is one main cause for biodiversity loss. This impact is particularly high and less researched in aquatic systems and microbial organisms and despite the high impact, the knowledge about overall mechanisms and specific factors affecting invasions are not fully understood. In general, the characteristics of the habitat, native community and invader determine the invasiveness.
In this thesis, I aimed to provide a better understanding of aquatic invasions focusing on the invader and its traits and identity. This thesis used a set of 12 strains of the invasive cyanobacterium Cylindrospermopsis raciborskii to examine the effect and impact of the invaders’ identity and genetic diversity. Further, the effect of timing on the invasion potential and success was determined, because aquatic systems in particular undergo seasonal fluctuations.
Most studies revealed a higher invasion success with increasing genetic diversity. Here, the increase of the genetic diversity, by either strain richness or phylogenetic dissimilarity, is not firstly driving the invasion, but the strain-identity. The high variability among the strains in traits important for invasions led to the highly varying strain-specific invasion success. This success was most dependent on nitrogen uptake and efficient resource use. The lower invasion success into communities comprising further N-fixing species indicates C. raciborskii can use this advantage only without the presence of competitive species. The relief of grazing pressure, which is suggested to be more important in aquatic invasions, was only promoting the invasion when unselective and larger consumers were present. High abundances of unselective consumers hampered the invasion success.
This indicates a more complex and temporal interplay of competitive and consumptive resistance mechanisms during the invasion process. Further, the fluctuation abundance and presence of competitors (= primary producers) and consumers (= zooplankton) in lakes can open certain ‘invasion windows’.
Remarkably, the composition of the resident community was also strain-specific affected and altered, independent of a high or low invasion success. Prior, this was only documented on the species level. Further, investigations on the population of invasive strains can reveal more about the invasion patterns and how multiple strain invasions change resident communities.
The present dissertation emphasises the importance of invader-addition experiments with a community context and the importance of the strain-level for microbial invasions and in general, e.g. for community assemblies and the outcome of experiments. The strain-specific community changes, also after days, may explain some sudden changes in communities, which have not been explained yet. This and further knowledge may also facilitate earlier and less cost-intensive management to step in, because these species are rarely tracked until they reach a high abundance or bloom, because of their small size.
Concluded for C. raciborskii, it shows that this species is no ‘generalistic’ invader and its invasion success depends more on the competitor presence than grazing pressure. This may explain its, still unknown, invasion pattern, as C. raciborskii is not found in all lakes of a region.
N2 - Biologische Invasionen beschreiben die Ausbreitung und Etablierung von Arten außerhalb ihres natürlichen Verbreitungsgebiets. Das Eindringen dieser invasiven Arten in ein neues Ökosystem hat meist negative Auswirkungen. Beispiele sind unter anderem veränderte Ökosystemprozesse, Lebensräume und Zusammensetzungen der einheimischen Arten, die zu einem Verlust der biologischen Vielfalt führen. Durch die fortschreitende Globalisierung und den Klimawandel steigt die Anzahl invasiver Arten weltweit. Um dies möglichst zu verhindern, müssen die zugrundeliegenden Mechanismen und Faktoren verstanden sein. Besonders bei aquatischen Mikroorganismen ist die Wissenslücke dabei groß und umso drängender, da diese Arten ein hohes Invasionspotential und potentiell stärkere negative Auswirkungen haben.
Die vorliegende Dissertation untersuchte anhand der invasiven Cyanobakterie Cylindrospermopsis raciborskii, den anfänglichen Invasionsprozess, unter besonderer Berücksichtigung der Stamm-Identität, der genetischen Diversität und des Zeitpunkts der Invasion.
Die meisten Studien zu Invasionen zeigen einen positiven Effekt der genetischen Diversität auf Invasionen. Diese Arbeit konnte zeigen, dass der Invasionserfolg auf bestimmte Stamm-spezifische Eigenschaften zurückzuführen ist. Für C. raciborskii war dies eine erhöhte Aufnahme von Stickstoff und eine effizientere Nutzung von Ressourcen. Wie einige andere aquatischen Arten hat C. raciborskii die Fähigkeit über differenzierte Zellen Stickstoff aus der Luft zu fixieren. Des Weiteren fördern bestimmte Umweltbedingungen, wie eine niedrige Nährstoffkonzentration, das Wachstum von C. raciborskii.
Fraßdruck wirkte sich nur negativ aus, wenn unselektive Prädatoren anwesend waren. Zudem zeigten weitere Versuche, dass ihr Konkurrenzvorteil nur in Gemeinschaften ohne weitere Stickstoff-Fixierer und in Stickstoff-reduzierten Habitaten die Etablierung positiv beeinflusst.
Diese Erkenntnisse lassen darauf schließen, dass diverse Eigenschaften und eine zeitliche Abfolge dieser, den Invasionserfolg beeinflussen. Dieser kann einerseits durch den Widerstand der heimischen Arten-Gemeinschaft und zum anderem durch die herrschenden abiotischen Bedingungen verhindert werden. Gerade aquatische Systeme unterlaufen saisonalen Schwankungen und diese erlauben somit bestimmte, temporäre Invasionsmöglichkeiten. Zusätzlich führte die Stamm-Identität zu Änderungen in der einheimischen Artenzusammensetzung, unabhängig vom Erfolg der Invasion - dies wurde bis jetzt nur Art-spezifisch gezeigt.
Damit betont die vorliegende Arbeit die Bedeutung von Stamm-Identitäten auf Invasionen und deren Auswirkungen auf ökologische Prozesse und den Ausgang von Experimenten. Zusammengefasst für C. raciborskii zeigt die Arbeit, dass diese Art keine ‚generell‘ erfolgreiche invasive Art ist und dass der Invasionserfolg eher von den vorhanden konkurrierenden Arten abhängt. Dies könnte das noch unklare Ausbreitungs-Muster erklären.
KW - invasion
KW - cyanobacteria
KW - population
KW - Cylindrospermopsis raciborskii
Y1 - 2018
ER -