TY - JOUR A1 - Braga, Raul Renno A1 - Gomez-Aparicio, Lorena A1 - Heger, Tina A1 - Simoes Vitule, Jean Ricardo A1 - Jeschke, Jonathan M. T1 - Structuring evidence for invasional meltdown BT - broad support but with biases and gaps JF - Biological invasions : unique international journal uniting scientists in the broad field of biological invasions N2 - Negative interactions have been suggested as a major barrier for species arriving in a new habitat. More recently, positive interactions drew attention from community assembly theory and invasion science. The invasional meltdown hypothesis (IMH) introduced the idea that positive interactions among non-native species could facilitate one another’s invasion, even increasing their impact upon the native community. Many studies have addressed IMH, but with contrasting results, reflecting various types of evidence on a multitude of scales. Here we use the hierarchy-of-hypotheses (HoH) approach to differentiate key aspects of IMH, organizing and linking empirical studies to sub-hypotheses of IMH. We also assess the level of empirical support for each sub-hypothesis based on the evidence reported in the studies. We identified 150 studies addressing IMH. The majority of studies support IMH, but the evidence comes from studies with different aims and questions. Supporting studies at the community or ecosystem level are currently rare. Evidence is scarce for marine habitats and vertebrates. Few sub-hypotheses are questioned by more than 50% of the evaluated studies, indicating that non-native species do not affect each other’s survival, growth, reproduction, abundance, density or biomass in reciprocal A ↔ B interactions. With the HoH for IMH presented here, we can monitor progress in empirical tests and evidences of IMH. For instance, more tests at the community and ecosystem level are needed, as these are necessary to address the core of this hypothesis. KW - Facilitation KW - Mutualism KW - Review KW - Nonindigenous KW - Exotic Y1 - 2018 U6 - https://doi.org/10.1007/s10530-017-1582-2 SN - 1387-3547 SN - 1573-1464 VL - 20 IS - 4 SP - 923 EP - 936 PB - Springer CY - Dordrecht ER - TY - THES A1 - Ting, Michael Kien Yin T1 - Circadian-regulated dynamics of translation in Arabidopsis thaliana Y1 - 2021 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 - 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 - Bhat, Javaid Y. A1 - Milicic, Goran A1 - Thieulin-Pardo, Gabriel A1 - Bracher, Andreas A1 - Maxwell, Andrew A1 - Ciniawsky, Susanne A1 - Müller-Cajar, Oliver A1 - Engen, John R. A1 - Hartl, F. Ulrich A1 - Wendler, Petra A1 - Hayer-Hartl, Manajit T1 - Mechanism of Enzyme Repair by the AAA(+) Chaperone Rubisco Activase JF - Molecular cell N2 - How AAA(+) chaperones conformationally remodel specific target proteins in an ATP-dependent manner is not well understood. Here, we investigated the mechanism of the AAA(+) protein Rubisco activase (Rca) in metabolic repair of the photosynthetic enzyme Rubisco, a complex of eight large (RbcL) and eight small (RbcS) subunits containing eight catalytic sites. Rubisco is prone to inhibition by tight-binding sugar phosphates, whose removal is catalyzed by Rca. We engineered a stable Rca hexamer ring and analyzed its functional interaction with Rubisco. Hydrogen/deuterium exchange and chemical crosslinking showed that Rca structurally destabilizes elements of the Rubisco active site with remarkable selectivity. Cryo-electron microscopy revealed that Rca docks onto Rubisco over one active site at a time, positioning the C-terminal strand of RbcL, which stabilizes the catalytic center, for access to the Rca hexamer pore. The pulling force of Rca is fine-tuned to avoid global destabilization and allow for precise enzyme repair. Y1 - 2017 U6 - https://doi.org/10.1016/j.molcel.2017.07.004 SN - 1097-2765 SN - 1097-4164 VL - 67 SP - 744 EP - 756 PB - Cell Press CY - Cambridge ER - TY - JOUR A1 - Park, Misoon A1 - Krause, Cornelia A1 - Karnahl, Matthias A1 - Reichardt, Ilka A1 - El Kasmi, Farid A1 - Mayer, Ulrike A1 - Stierhof, York-Dieter A1 - Hiller, Ulrike A1 - Strompen, Georg A1 - Bayer, Martin A1 - Kientz, Marika A1 - Sato, Masa H. A1 - Nishimura, Marc T. A1 - Dangl, Jeffery L. A1 - Sanderfoot, Anton A. A1 - Jürgens, Gerd T1 - Concerted Action of Evolutionarily Ancient and Novel SNARE Complexes in Flowering-Plant Cytokinesis JF - Developmental cell N2 - Membrane vesicles delivered to the cell-division plane fuse with one another to form the partitioning membrane during plant cytokinesis, starting in the cell center. In Arabidopsis, this requires SNARE complexes involving the cytokinesis-specific Qa-SNARE KNOLLE. However, cytokinesis still occurs in knolle mutant embryos, suggesting contributions from KNOLLE-independent SNARE complexes. Here we show that Qa-SNARE SYP132, having counterparts in lower plants, functionally overlaps with the flowering plant-specific KNOLLE. SYP132 mutation causes cytokinesis defects, knolle syp132 double mutants consist of only one or a few multi-nucleate cells, and SYP132 has the same SNARE partners as KNOLLE. SYP132 and KNOLLE also have non-overlapping functions in secretion and in cellularization of the embryo-nourishing endosperm resulting from double fertilization unique to flowering plants. Evolutionarily ancient non-specialized SNARE complexes originating in algae were thus amended by the appearance of cytokinesis-specific SNARE complexes, meeting the high demand for membrane-fusion capacity during endosperm cellularization in angiosperms. Y1 - 2018 U6 - https://doi.org/10.1016/j.devcel.2017.12.027 SN - 1534-5807 SN - 1878-1551 VL - 44 IS - 4 SP - 500 EP - + PB - Cell Press CY - Cambridge ER - TY - JOUR A1 - Weithoff, Guntram A1 - Taube, Anne A1 - Bolius, Sarah T1 - The invasion success of the cyanobacterium Cylindrospermopsis raciborskii in experimental mesocosms BT - genetic identity, grazing loss, competition and biotic resistance JF - Aquatic Invasions N2 - The potentially toxic, invasive cyanobacterium Cylindrospermopsis raciborskii, originating from sub-tropical regions, has spread into temperate climate zones in almost all continents. Potential factors in its success are temperature, light and nutrient levels. Grazing losses through zooplankton have been measured in the laboratory but are typically not regarded as a factor in (failed) invasion success. In some potentially suitable lakes, C. raciborskii has never been found, although it is present in water bodies close by. Therefore, we tested the invasive potential of three different isolates introduced into natural plankton communities using laboratory mesocosm experiments under three grazing levels: ambient zooplankton densities, removal of large species using 100 mu m mesh and a ca. doubling of large species. Three C. raciborskii isolates originating from the same geographic region (North-East Germany) were added separately to the four replicates of each treatment and kept in semi-continuous cultures for 21 days. Two isolates disappeared from the mesocosms and were also not viable in filtered lake water indicating that the lake water itself or the switch from culture medium to lake water led to the decay of the inoculated C. raciborskii. Only one out of the three isolates persisted in the plankton communities at a rather low level and only in the treatment without larger zooplankton. This result demonstrates that under potentially suitable environmental conditions, top-down control from zooplankton might hamper the establishment of C. raciborskii. Non-metric multidimensional scaling showed distinct variation in resident phytoplankton communities between the different grazing levels, thus differential grazing impact shaped the resident community in different ways allowing C. raciborskii only to invade under competitive (= low grazing pressure) conditions. Furthermore, even after invasion failure, the temporary presence of C. raciborskii influenced the phytoplankton community. KW - alien species KW - Cyanobacteria KW - competitive resistance KW - consumptive resistance KW - herbivory KW - harmful algae KW - microbial invasion Y1 - 2017 U6 - https://doi.org/10.3391/ai.2017.12.3.07 SN - 1798-6540 SN - 1818-5487 VL - 12 SP - 333 EP - 341 PB - Regional Euro-Asian Biological Invasions centre-reabic CY - Helsinki ER - TY - JOUR A1 - Kaufmann, Hans Paul A1 - Duffus, Benjamin R. A1 - Mitrova, Biljana A1 - Iobbi-Nivol, Chantal A1 - Teutloff, Christian A1 - Nimtz, Manfred A1 - Jaensch, Lothar A1 - Wollenberger, Ulla A1 - Leimkühler, Silke T1 - Modulating the Molybdenum Coordination Sphere of Escherichia coli Trimethylamie N-Oxide Reductase JF - Biochemistry N2 - The well-studied enterobacterium Escherichia coli present in the human gut can reduce trimethylamine N-oxide (TMAO) to trimethylamine during anaerobic respiration. The TMAO reductase TorA is a monomeric, bis-molybdopterin guanine dinucleotide (bis-MGD) cofactor-containing enzyme that belongs to the dimethyl sulfoxide reductase family of molybdoenzymes. We report on a system for the in vitro reconstitution of TorA with molybdenum cofactors (Moco) from different sources. Higher TMAO reductase activities for TorA were obtained when using Moco sources containing a sulfido ligand at the molybdenum atom. For the first time, we were able to isolate functional bis-MGD from Rhodobacter capsulatus formate dehydrogenase (FDH), which remained intact in its isolated state and after insertion into apo-TorA yielded a highly active enzyme. Combined characterizations of the reconstituted TorA enzymes by electron paramagnetic resonance spectroscopy and direct electrochemistry emphasize that TorA activity can be modified by changes in the Mo coordination sphere. The combination of these results together with studies of amino acid exchanges at the active site led us to propose a novel model for binding of the substrate to the molybdenum atom of TorA. Y1 - 2018 U6 - https://doi.org/10.1021/acs.biochem.7b01108 SN - 0006-2960 VL - 57 IS - 7 SP - 1130 EP - 1143 PB - American Chemical Society CY - Washington ER - TY - JOUR A1 - Sustr, David A1 - Hlaváček, Antonín A1 - Duschl, Claus A1 - Volodkin, Dmitry T1 - Multi-fractional analysis of molecular diffusion in polymer multilayers by FRAP BT - a new simulation-based approach JF - The journal of physical chemistry : B, Condensed matter, materials, surfaces, interfaces & biophysical N2 - Comprehensive analysis of the multifractional molecular diffusion provides a deeper understanding of the diffusion phenomenon in the fields of material science, molecular and cell biology, advanced biomaterials, etc. Fluorescence recovery after photobleaching (FRAP) is commonly employed to probe the molecular diffusion. Despite FRAP being a very popular method, it is not easy to assess multifractional molecular diffusion due to limited possibilities of approaches for analysis. Here we present a novel simulation-optimization-based approach (S-approach) that significantly broadens possibilities of the analysis. In the S-approach, possible fluorescence recovery scenarios are primarily simulated and afterward compared with a real measurement while optimizing parameters of a model until a sufficient match is achieved. This makes it possible to reveal multifractional molecular diffusion. Fluorescent latex particles of different size and fluorescein isothiocyanate in an aqueous medium were utilized as test systems. Finally, the S-approach has been used to evaluate diffusion of cytochrome c loaded into multilayers made of hyaluronan and polylysine. Software for evaluation of multifractional molecular diffusion by S-approach has been developed aiming to offer maximal versatility and user-friendly way for analysis. Y1 - 2017 U6 - https://doi.org/10.1021/acs.jpcb.7b11051 SN - 1520-6106 VL - 122 IS - 3 SP - 1323 EP - 1333 PB - American Chemical Society CY - Washington ER - TY - JOUR A1 - Bukowski, Alexandra R. A1 - Schittko, Conrad A1 - Petermann, Jana S. T1 - The strength of negative plant-soil feedback increases from the intraspecific to the interspecific and the functional group level JF - Ecology and evolution N2 - One of the processes that may play a key role in plant species coexistence and ecosystem functioning is plant-soil feedback, the effect of plants on associated soil communities and the resulting feedback on plant performance. Plant-soil feedback at the interspecific level (comparing growth on own soil with growth on soil from different species) has been studied extensively, while plant-soil feedback at the intraspecific level (comparing growth on own soil with growth on soil from different accessions within a species) has only recently gained attention. Very few studies have investigated the direction and strength of feedback among different taxonomic levels, and initial results have been inconclusive, discussing phylogeny, and morphology as possible determinants. To test our hypotheses that the strength of negative feedback on plant performance increases with increasing taxonomic level and that this relationship is explained by morphological similarities, we conducted a greenhouse experiment using species assigned to three taxonomic levels (intraspecific, interspecific, and functional group level). We measured certain fitness-related aboveground traits and used them along literature-derived traits to determine the influence of morphological similarities on the strength and direction of the feedback. We found that the average strength of negative feedback increased from the intraspecific over the interspecific to the functional group level. However, individual accessions and species differed in the direction and strength of the feedback. None of our results could be explained by morphological dissimilarities or individual traits. Synthesis. Our results indicate that negative plant-soil feedback is stronger if the involved plants belong to more distantly related species. We conclude that the taxonomic level is an important factor in the maintenance of plant coexistence with plant-soil feedback as a potential stabilizing mechanism and should be addressed explicitly in coexistence research, while the traits considered here seem to play a minor role. KW - Arabidopsis thaliana Col-0 KW - home-away effect KW - intraspecific diversity KW - morphological similarities KW - dissimilarities of plants KW - plant-soil (belowground) interactions KW - species coexistence KW - taxonomic levels KW - trait measurements Y1 - 2018 U6 - https://doi.org/10.1002/ece3.3755 SN - 2045-7758 VL - 8 IS - 4 SP - 2280 EP - 2289 PB - Wiley CY - Hoboken 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 - Luckner, Madlen A1 - Dunsing, Valentin A1 - Chiantia, Salvatore A1 - Hermann, Andreas T1 - Oligomerization and nuclear shuttling dynamics of viral proteins studied by quantitative molecular brightness analysis using fluorescence correlation spectroscopy T2 - Biophysical journal Y1 - 2018 U6 - https://doi.org/10.1016/j.bpj.2017.11.1951 SN - 0006-3495 SN - 1542-0086 VL - 114 IS - 3 SP - 350A EP - 350A PB - Cell Press CY - Cambridge 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 - Stoessel, Daniel A1 - Schulte, Claudia A1 - dos Santos, Marcia C. Teixeira A1 - Scheller, Dieter A1 - Rebollo-Mesa, Irene A1 - Deuschle, Christian A1 - Walther, Dirk A1 - Schauer, Nicolas A1 - Berg, Daniela A1 - da Costa, Andre Nogueira A1 - Maetzler, Walter T1 - Promising Metabolite Profiles in the Plasma and CSF of Early Clinical JF - Frontiers in Aging Neuroscience N2 - Parkinson's disease (PD) shows high heterogeneity with regard to the underlying molecular pathogenesis involving multiple pathways and mechanisms. Diagnosis is still challenging and rests entirely on clinical features. Thus, there is an urgent need for robust diagnostic biofluid markers. Untargeted metabolomics allows establishing low-molecular compound biomarkers in a wide range of complex diseases by the measurement of various molecular classes in biofluids such as blood plasma, serum, and cerebrospinal fluid (CSF). Here, we applied untargeted high-resolution mass spectrometry to determine plasma and CSF metabolite profiles. We semiquantitatively determined small-molecule levels (<= 1.5 kDa) in the plasma and CSF from early PD patients (disease duration 0-4 years; n = 80 and 40, respectively), and sex-and age-matched controls (n = 76 and 38, respectively). We performed statistical analyses utilizing partial least square and random forest analysis with a 70/30 training and testing split approach, leading to the identification of 20 promising plasma and 14 CSF metabolites. The semetabolites differentiated the test set with an AUC of 0.8 (plasma) and 0.9 (CSF). Characteristics of the metabolites indicate perturbations in the glycerophospholipid, sphingolipid, and amino acid metabolism in PD, which underscores the high power of metabolomic approaches. Further studies will enable to develop a potential metabolite-based biomarker panel specific for PD KW - biomarker KW - untargeted metabolomics KW - neurodegeneration KW - plasma KW - CSF KW - machinelearning Y1 - 2018 U6 - https://doi.org/10.3389/fnagi.2018.00051 SN - 1663-4365 VL - 10 PB - Frontiers Research Foundation CY - Lausanne ER - TY - THES A1 - Brunacci, Nadia T1 - Oligodepsipeptides as matrix for drug delivery systems and submicron particulate carriers Y1 - 2021 ER - TY - JOUR A1 - Palkopoulou, Eleftheria A1 - Lipson, Mark A1 - Mallick, Swapan A1 - Nielsen, Svend A1 - Rohland, Nadin A1 - Baleka, Sina Isabelle A1 - Karpinski, Emil A1 - Ivancevici, Atma M. A1 - Thu-Hien To, A1 - Kortschak, Daniel A1 - Raison, Joy M. A1 - Qu, Zhipeng A1 - Chin, Tat-Jun A1 - Alt, Kurt W. A1 - Claesson, Stefan A1 - Dalen, Love A1 - MacPhee, Ross D. E. A1 - Meller, Harald A1 - Rocar, Alfred L. A1 - Ryder, Oliver A. A1 - Heiman, David A1 - Young, Sarah A1 - Breen, Matthew A1 - Williams, Christina A1 - Aken, Bronwen L. A1 - Ruffier, Magali A1 - Karlsson, Elinor A1 - Johnson, Jeremy A1 - Di Palma, Federica A1 - Alfoldi, Jessica A1 - Adelsoni, David L. A1 - Mailund, Thomas A1 - Munch, Kasper A1 - Lindblad-Toh, Kerstin A1 - Hofreiter, Michael A1 - Poinar, Hendrik A1 - Reich, David T1 - A comprehensive genomic history of extinct and living elephants JF - Proceedings of the National Academy of Sciences of the United States of America KW - paleogenomics KW - elephantid evolution KW - mammoth KW - admixture KW - species divergence Y1 - 2018 U6 - https://doi.org/10.1073/pnas.1720554115 SN - 0027-8424 VL - 115 IS - 11 SP - E2566 EP - E2574 PB - National Acad. of Sciences CY - Washington 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 - GEN A1 - Dammhahn, Melanie A1 - Dingemanse, Niels J. A1 - Niemelae, Petri T. A1 - Reale, Denis T1 - Pace-of-life syndromes BT - a framework for the adaptive integration of behaviour, physiology and life history T2 - Behavioral ecology and sociobiology N2 - This introduction to the topical collection on Pace-of-life syndromes: a framework for the adaptive integration of behaviour, physiology, and life history provides an overview of conceptual, theoretical, methodological, and empirical progress in research on pace-of-life syndromes (POLSs) over the last decade. The topical collection has two main goals. First, we briefly describe the history of POLS research and provide a refined definition of POLS that is applicable to various key levels of variation (genetic, individual, population, species). Second, we summarise the main lessons learned from current POLS research included in this topical collection. Based on an assessment of the current state of the theoretical foundations and the empirical support of the POLS hypothesis, we propose (i) conceptual refinements of theory, particularly with respect to the role of ecology in the evolution of (sexual dimorphism in) POLS, and (ii) methodological and statistical approaches to the study of POLS at all major levels of variation. This topical collection further holds (iii) key empirical examples demonstrating how POLS structures may be studied in wild populations of (non) human animals, and (iv) a modelling paper predicting POLS under various ecological conditions. Future POLS research will profit from the development of more explicit theoretical models and stringent empirical tests of model assumptions and predictions, increased focus on how ecology shapes (sex-specific) POLS structures at multiple hierarchical levels, and the usage of appropriate statistical tests and study designs. Significance statement As an introduction to the topical collection, we summarise current conceptual, theoretical, methodological and empirical progress in research on pace-of-life syndromes (POLSs), a framework for the adaptive integration of behaviour, physiology and life history at multiple hierarchical levels of variation (genetic, individual, population, species). Mixed empirical support of POLSs, particularly at the within-species level, calls for an evaluation and refinement of the hypothesis. We provide a refined definition of POLSs facilitating testable predictions. Future research on POLSs will profit from the development of more explicit theoretical models and stringent empirical tests of model assumptions and predictions, increased focus on how ecology shapes (sex-specific) POLSs structures at multiple hierarchical levels and the usage of appropriate statistical tests and study designs. Y1 - 2018 U6 - https://doi.org/10.1007/s00265-018-2473-y SN - 0340-5443 SN - 1432-0762 VL - 72 IS - 3 PB - Springer CY - New York ER - TY - GEN A1 - Dahmani, Ismail A1 - Ludwig, Kai A1 - Chiantia, Salvatore T1 - Influenza A matrix protein M1 induces lipid membrane deformation via protein multimerization T2 - Postprints der Universität Potsdam Mathematisch-Naturwissenschaftliche Reihe N2 - The matrix protein M1 of the Influenza A virus (IAV) is supposed to mediate viral assembly and budding at the plasma membrane (PM) of infected cells. In order for a new viral particle to form, the PM lipid bilayer has to bend into a vesicle toward the extracellular side. Studies in cellular models have proposed that different viral proteins might be responsible for inducing membrane curvature in this context (including M1), but a clear consensus has not been reached. In the present study, we use a combination of fluorescence microscopy, cryogenic transmission electron microscopy (cryo-TEM), cryo-electron tomography (cryo-ET) and scanning fluorescence correlation spectroscopy (sFCS) to investigate M1-induced membrane deformation in biophysical models of the PM. Our results indicate that M1 is indeed able to cause membrane curvature in lipid bilayers containing negatively charged lipids, in the absence of other viral components. Furthermore, we prove that protein binding is not sufficient to induce membrane restructuring. Rather, it appears that stable M1–M1 interactions and multimer formation are required in order to alter the bilayer three-dimensional structure, through the formation of a protein scaffold. Finally, our results suggest that, in a physiological context,M1-induced membrane deformation might be modulated by the initial bilayer curvature and the lateral organization of membrane components (i.e. the presence of lipid domains). T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 768 KW - confocal microscopy KW - influenza KW - lipid membranes KW - membranes KW - protein-protein interactions KW - viral matrix proteins Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-438689 SN - 1866-8372 IS - 768 ER - TY - JOUR A1 - Schmidt, Marco F. T1 - miRNA Targeting Drugs BT - the next blockbusters? JF - Drug Target miRNA: Methods and Protocols N2 - Only 20 years after the discovery of small non-coding, single-stranded ribonucleic acids, so-called microRNAs (miRNAs), as post-transcriptional gene regulators, the first miRNA-targeting drug Miravirsen for the treatment of hepatitis C has been successfully tested in clinical Phase II trials. Addressing miRNAs as drug targets may enable the cure, or at least the treatment of diseases, which presently seems impossible. However, due to miRNAs’ chemical structure, generation of potential drug molecules with necessary pharmacokinetic properties is still challenging and requires a re-thinking of the drug discovery process. Therefore, this chapter highlights the potential of miRNAs as drug targets, discusses the challenges, and tries to give a complete overview of recent strategies in miRNA drug discovery. KW - miRNA KW - Drug discovery KW - microRNA-induced silencing complex KW - Antisense agents KW - Small-molecule miRNA modulators KW - Argonaute 2 protein Y1 - 2016 SN - 978-1-4939-6563-2 SN - 978-1-4939-6561-8 U6 - https://doi.org/10.1007/978-1-4939-6563-2_1 SN - 1064-3745 SN - 1940-6029 VL - 1517 SP - 3 EP - 22 PB - Springer CY - New York ER - TY - BOOK ED - Schmidt, Marco F. T1 - Drug target miRNA BT - methods and protocols T3 - Methods in Molecular Biology N2 - This volume provides a concise and technical discussion of recently developed approaches to overcome challenges in miRNA drug discovery. Drug Target miRNA: Methods and Protocols explores strategies to overcome pharmacodynamics and pharmacokinetics challenges. These strategies cover anti-sense agents targeting miRNA that are applied in advanced formulations or are chemically optimized to increase delivery; small molecule miRNA modulators to overcome anti-sense agents’ limitations; general enhancers of miRNA maturation; and Argonaute 2 protein and its pharmacokinetic parameters. Written in the highly successful Methods in Molecular Biology series format, chapters include introductions to their respective topics, lists of the necessary materials and reagents, step-by-step, readily reproducible laboratory protocols, and tips on troubleshooting and avoiding known pitfalls.Cutting-edge and thorough, Drug Target miRNA: Methods and Protocols is a valuable resource for anyone interested in the ever-evolving field of miRNA drug discovery. Y1 - 2017 SN - 978-1-4939-6561-8 SN - 978-1-4939-6563-2 U6 - https://doi.org/10.1007/978-1-4939-6563-2 SN - 1064-3745 SN - 1940-6029 PB - Springer CY - New York ER - TY - CHAP A1 - Schmidt, Marco F. ED - Schmidt, Marco F. T1 - Preface T2 - Drug target miRNA Y1 - 2016 SN - 978-1-4939-6563-2 SN - 978-1-4939-6561-8 U6 - https://doi.org/10.1007/978-1-4939-6563-2 SN - 1064-3745 SN - 1940-6029 VL - 1517 SP - V EP - V PB - Springer CY - New York ER - TY - JOUR A1 - Trindade, Ines T1 - A shelter for the future BT - how WUSCHEL protects the shoot apical meristem from viral infection JF - Molecular plant N2 - Plant development in its majority occurs post-embryonically through the activity of local meristems that provide daughter cells for the development of new organs. It has long been acknowledged that the shoot apical meristem (SAM), which holds the stem cells that will form above-ground organs, is recalcitrant to infection by multiple pathogens, a crucial strategy to safeguard normal devel- opment and subsequent generations. However, the molecular mechanisms underlying SAM immunity remain largely unknown. Y1 - 2020 U6 - https://doi.org/10.1016/j.molp.2020.11.009 SN - 1674-2052 SN - 1752-9867 VL - 13 IS - 12 SP - 1675 EP - 1675 PB - Cell Press CY - Cambridge ER - TY - JOUR A1 - Weingart, C. A1 - Raila, Jens A1 - Lübke-Becker, A. A1 - Kershaw, O. A1 - Brunnberg, M. A1 - Kohn, B. T1 - Calcitriol induced hypercalcemia in a hunting dog with a disseminated Paecilomyces variotii infection T1 - Calcitriol-bedingte Hyperkalzämie bei einem Jagdhund mit disseminierter Paecilomyces variotii-Infektion JF - Schweizer Archiv für Tierheilkunde N2 - A 5-year old hunting dog was presented with reduced appetite, weight loss and polyuria/polydipsia. Hematology and clinical chemistry revealed anemia, leukocytosis, increased liver enzymes, hypoalbuminemia and hypercalcemia. The cytological, pathohistological and microbiological examination identified a disseminated infection with the saprophytic mould fungus Paecilomyces variotii in the biopsies of the spleen and a lymph node. Determination of vitamin D metabolites confirmed a calcitriol induced hypercalcemia. N2 - Ein 5-jähriger Jagdhund wurde wegen verminderter Futteraufnahme, Gewichtsverlust und Polyurie/Polydipsie vorgestellt. In der hämatologischen und klinisch-chemischen Blutuntersuchung wurde neben einer Anämie und Leukozytose eine Erhöhung der Leberenzyme, Hypoalbuminämie und Hyperkalzämie festgestellt. Durch zytologische, pathohistologische und mikrobiologische Untersuchungen von Biopsien aus Milz und Lymphknoten konnte eine systemische Schimmelpilzinfektion mit Paecilomyces variotii nachgewiesen werden. Die Bestimmung der Vitamin-D-Metabolite bestätigte das Vorliegen einer Hyperkalzämie infolge einer Erhöhung der Calcitriolkonzentration. KW - mould fungus KW - calcium KW - polyuria/polydipsia KW - dog KW - Schimmelpilzinfektion KW - Kalzium KW - Polyurie/ Polydipsie KW - Hund Y1 - 2018 U6 - https://doi.org/10.17236/sat00161 SN - 0036-7281 SN - 1664-2848 IS - 5 SP - 313 EP - 319 PB - Gesellschaft Schweizer Tierärztinnen und Tierärzte CY - Bern ET - 160 ER - TY - GEN A1 - Ceulemans, Ruben A1 - Gaedke, Ursula A1 - Klauschies, Toni A1 - Guill, Christian T1 - The effects of functional diversity on biomass production, variability, and resilience of ecosystem functions in a tritrophic system T2 - Postprints der Universität Potsdam Mathematisch-Naturwissenschaftliche Reihe N2 - Diverse communities can adjust their trait composition to altered environmental conditions, which may strongly influence their dynamics. Previous studies of trait-based models mainly considered only one or two trophic levels, whereas most natural system are at least tritrophic. Therefore, we investigated how the addition of trait variation to each trophic level influences population and community dynamics in a tritrophic model. Examining the phase relationships between species of adjacent trophic levels informs about the strength of top-down or bottom-up control in non-steadystate situations. Phase relationships within a trophic level highlight compensatory dynamical patterns between functionally different species, which are responsible for dampening the community temporal variability. Furthermore, even without trait variation, our tritrophic model always exhibits regions with two alternative states with either weak or strong nutrient exploitation, and correspondingly low or high biomass production at the top level. However, adding trait variation increased the basin of attraction of the high-production state, and decreased the likelihood of a critical transition from the high- to the lowproduction state with no apparent early warning signals. Hence, our study shows that trait variation enhances resource use efficiency, production, stability, and resilience of entire food webs. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 744 KW - early-warning signals KW - top-down control KW - community ecology KW - regime shifts KW - food webs KW - compensatory dynamics KW - consumer diversity KW - metabolic theory KW - rapid evolution KW - stable states Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-435439 SN - 1866-8372 IS - 744 ER - TY - GEN A1 - Porada, Philipp A1 - Tamm, Alexandra A1 - Raggio, Jose A1 - Yafang, Cheng A1 - Kleidon, Axel A1 - Pöschl, Ulrich A1 - Weber, Bettina T1 - Global NO and HONO emissions of biological soil crusts estimated by a process-based non-vascular vegetation model T2 - Postprints der Universität Potsdam Mathematisch-Naturwissenschaftliche Reihe N2 - The reactive trace gases nitric oxide (NO) and nitrous acid (HONO) are crucial for chemical processes in the atmosphere, including the formation of ozone and OH radicals, oxidation of pollutants, and atmospheric self-cleaning. Recently, empirical studies have shown that biological soil crusts are able to emit large amounts of NO and HONO, and they may therefore play an important role in the global budget of these trace gases. However, the upscaling of local estimates to the global scale is subject to large uncertainties, due to unknown spatial distribution of crust types and their dynamic metabolic activity. Here, we perform an alternative estimate of global NO and HONO emissions by biological soil crusts, using a process-based modelling approach to these organisms, combined with global data sets of climate and land cover. We thereby consider that NO and HONO are emitted in strongly different proportions, depending on the type of crust and their dynamic activity, and we provide a first estimate of the global distribution of four different crust types. Based on this, we estimate global total values of 1.04 Tg yr⁻¹ NO–N and 0.69 Tg yr⁻¹ HONO–N released by biological soil crusts. This corresponds to around 20% of global emissions of these trace gases from natural ecosystems. Due to the low number of observations on NO and HONO emissions suitable to validate the model, our estimates are still relatively uncertain. However, they are consistent with the amount estimated by the empirical approach, which confirms that biological soil crusts are likely to have a strong impact on global atmospheric chemistry via emissions of NO and HONO. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 746 KW - net primary productivity KW - hilly loes plateau KW - mojave desert KW - spatial-distribution KW - nitrous-oxide KW - succulent karoo KW - inner-mongolia KW - carbon KW - lichens KW - bryophytes Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-435682 SN - 1866-8372 IS - 746 SP - 2003 EP - 2031 ER - TY - GEN A1 - Bierbach, David A1 - Schulte, Matthias A1 - Herrmann, Nina A1 - Tobler, Michael A1 - Stadler, Stefan A1 - Jung, Christian T. A1 - Kunkel, Benjamin A1 - Riesch, Rüdiger A1 - Klaus, Sebastian A1 - Ziege, Madlen A1 - Indy, Jeane Rimber A1 - Arias-Rodriguez, Lenin A1 - Plath, Martin T1 - Predator-induced changes of female mating preferences BT - innate and experiential effects T2 - Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - Background In many species males face a higher predation risk than females because males display elaborate traits that evolved under sexual selection, which may attract not only females but also predators. Females are, therefore, predicted to avoid such conspicuous males under predation risk. The present study was designed to investigate predator-induced changes of female mating preferences in Atlantic mollies (Poecilia mexicana). Males of this species show a pronounced polymorphism in body size and coloration, and females prefer large, colorful males in the absence of predators. Results In dichotomous choice tests predator-naïve (lab-reared) females altered their initial preference for larger males in the presence of the cichlid Cichlasoma salvini, a natural predator of P. mexicana, and preferred small males instead. This effect was considerably weaker when females were confronted visually with the non-piscivorous cichlid Vieja bifasciata or the introduced non-piscivorous Nile tilapia (Oreochromis niloticus). In contrast, predator experienced (wild-caught) females did not respond to the same extent to the presence of a predator, most likely due to a learned ability to evaluate their predators' motivation to prey. Conclusions Our study highlights that (a) predatory fish can have a profound influence on the expression of mating preferences of their prey (thus potentially affecting the strength of sexual selection), and females may alter their mate choice behavior strategically to reduce their own exposure to predators. (b) Prey species can evolve visual predator recognition mechanisms and alter their mate choice only when a natural predator is present. (c) Finally, experiential effects can play an important role, and prey species may learn to evaluate the motivational state of their predators. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 984 KW - sexual selection KW - female choice KW - non-independent mate choice KW - predator recognition KW - Poecilia mexicana Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-431099 SN - 1866-8372 IS - 984 ER - TY - GEN A1 - Baumann, Tobias A1 - Arndt, Katja Maren A1 - Müller, Kristian M. T1 - Directional cloning of DNA fragments using deoxyinosine-containing oligonucleotides and endonuclease V T2 - Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - Background: DNA fragments carrying internal recognition sites for the restriction endonucleases intended for cloning into a target plasmid pose a challenge for conventional cloning. Results: A method for directional insertion of DNA fragments into plasmid vectors has been developed. The target sequence is amplified from a template DNA sample by PCR using two oligonucleotides each containing a single deoxyinosine base at the third position from the 5' end. Treatment of such PCR products with endonuclease V generates 3' protruding ends suitable for ligation with vector fragments created by conventional restriction endonuclease reactions. Conclusions: The developed approach generates terminal cohesive ends without the use of Type II restriction endonucleases, and is thus independent from the DNA sequence. Due to PCR amplification, minimal amounts of template DNA are required. Using the robust Taq enzyme or a proofreading Pfu DNA polymerase mutant, the method is applicable to a broad range of insert sequences. Appropriate primer design enables direct incorporation of terminal DNA sequence modifications such as tag addition, insertions, deletions and mutations into the cloning strategy. Further, the restriction sites of the target plasmid can be either retained or removed. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 983 KW - cohesive ends KW - DNA cleavage KW - genetic vectors KW - modified primers KW - molecular methods KW - polymerase chain reaction KW - recombinant Escherichia coli KW - restriction enzymes Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-431085 SN - 1866-8372 IS - 983 ER - TY - GEN A1 - Riedel, Simona A1 - Siemiatkowska, Beata A1 - Watanabe, Mutsumi A1 - Müller, Christina S. A1 - Schünemann, Volker A1 - Hoefgen, Rainer A1 - Leimkühler, Silke T1 - The ABCB7-Like Transporter PexA in Rhodobacter capsulatus Is Involved in the Translocation of Reactive Sulfur Species T2 - Postprints der Universität Potsdam Mathematisch-Naturwissenschaftliche Reihe N2 - The mitochondrial ATP-binding cassette (ABC) transporters ABCB7 in humans, Atm1 in yeast and ATM3 in plants, are highly conserved in their overall architecture and particularly in their glutathione binding pocket located within the transmembrane spanning domains. These transporters have attracted interest in the last two decades based on their proposed role in connecting the mitochondrial iron sulfur (Fe–S) cluster assembly with its cytosolic Fe–S cluster assembly (CIA) counterpart. So far, the specific compound that is transported across the membrane remains unknown. In this report we characterized the ABCB7-like transporter Rcc02305 in Rhodobacter capsulatus, which shares 47% amino acid sequence identity with its mitochondrial counterpart. The constructed interposon mutant strain in R. capsulatus displayed increased levels of intracellular reactive oxygen species without a simultaneous accumulation of the cellular iron levels. The inhibition of endogenous glutathione biosynthesis resulted in an increase of total glutathione levels in the mutant strain. Bioinformatic analysis of the amino acid sequence motifs revealed a potential aminotransferase class-V pyridoxal-50-phosphate (PLP) binding site that overlaps with the Walker A motif within the nucleotide binding domains of the transporter. PLP is a well characterized cofactor of L-cysteine desulfurases like IscS and NFS1 which has a role in the formation of a protein-bound persulfide group within these proteins. We therefore suggest renaming the ABCB7-like transporter Rcc02305 in R. capsulatus to PexA for PLP binding exporter. We further suggest that this ABC-transporter in R. capsulatus is involved in the formation and export of polysulfide species to the periplasm. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 740 KW - ABCB7 KW - persulfide KW - polysulfide KW - glutathione KW - ABC transporter KW - Walker A motif KW - pyridoxal-50-phosphate Y1 - 1019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-434975 SN - 1866-8372 IS - 740 ER - TY - JOUR A1 - Tiedemann, Kim A1 - Iobbi-Nivol, Chantal A1 - Leimkühler, Silke T1 - The Role of the Nucleotides in the Insertion of the bis-Molybdopterin Guanine Dinucleotide Cofactor into apo-Molybdoenzymes JF - Molecules N2 - The role of the GMP nucleotides of the bis-molybdopterin guanine dinucleotide (bis-MGD) cofactor of the DMSO reductase family has long been a subject of discussion. The recent characterization of the bis-molybdopterin (bis-Mo-MPT) cofactor present in the E. coli YdhV protein, which differs from bis-MGD solely by the absence of the nucleotides, now enables studying the role of the nucleotides of bis-MGD and bis-MPT cofactors in Moco insertion and the activity of molybdoenzymes in direct comparison. Using the well-known E. coli TMAO reductase TorA as a model enzyme for cofactor insertion, we were able to show that the GMP nucleotides of bis-MGD are crucial for the insertion of the bis-MGD cofactor into apo-TorA. KW - bis-MGD KW - chaperone KW - molybdenum cofactor KW - TMAO reductase Y1 - 2022 U6 - https://doi.org/10.3390/molecules27092993 SN - 1420-3049 VL - 27 SP - 1 EP - 15 PB - MDPI CY - Basel, Schweiz ET - 9 ER - TY - JOUR A1 - Pospisil, Christina A1 - Czernitzki, Anna-Franziska A1 - Scheffler, Christiane T1 - No association between nutrition and body height in German kindergarten children BT - a pilot study JF - Journal of biological and clinical anthropology : Anthropologischer Anzeiger; Mitteilungsorgan der Gesellschaft für Anthropologie N2 - Anthropologists all over the world are discussing influences on individual height including quantity and quality of nutrition. To examine whether a relationship between nutritional components and height can be found this pilot study has been developed. The research samples consisted of 44 children (age 3–6 years) attending two different kindergartens in Germany. Height measurements were taken for each child. Furthermore the parents had to fill out a 24-hour questionnaire to document their children’s eating habits during the weekend. In order to standardize the measured height values z-scores were calculated with reference to the average height of the overall cohort. The results of correlation analysis indicate that height is not significantly related to any of the main nutritional components as protein (r = –0.148), carbohydrates (r = 0.126), fat (r = 0.107), fibre (r = –0.289), vitamin (r = 0.050), calcium (r = 0.110), potassium (r = 0.189) and overall calorie intake (r = 0.302). In conclusion, it can be stated that the quality of nutrition may not have a strong influence on individual height. However, due to the small sample size further research should be provided with a larger cohort of children to verify the present results. KW - nutritional components KW - individual body height KW - children KW - Germany Y1 - 2017 U6 - https://doi.org/10.1127/anthranz/2017/0704 SN - 0003-5548 SN - 2363-7099 VL - 74 IS - 3 SP - 199 EP - 202 PB - Schweizerbart CY - Stuttgart ER - TY - JOUR A1 - Czernitzki, Anna-Franziska A1 - Pospisil, Christina A1 - Musalek, Martin A1 - Mumm, Rebekka A1 - Scheffler, Christiane T1 - Analysis of longitudinal data of height z-scores in kindergarten children BT - a pilot study JF - Journal of biological and clinical anthropology : Anthropologischer Anzeiger ; Mitteilungsorgan der Gesellschaft für Anthropologie N2 - Changes in body height throughout extended historic periods are very complex and dynamic processes. Thispilot study aimed to investigate the pattern of longitudinal height z-scores changes in children before and after entering kindergarten. In summer 2016, we measured height and weight of 32 children from 4 groups of two kindergartens aged 3–6 years. All ages were centered according to the age of entry into the kindergarten. For each child we determined mean z-scores for height before and after entering the kindergarten, and assessed the variances for each kindergarten group. Twenty-two children targeted in height z-scores towards average height of their respective kindergarten group, 10 children did not. Due to the small numbers, the convergence in height variance however, remained insignificant (chi-squared independence test, p = 0.127). Additional studies with larger sample sizes are needed to confirm this pilot study. KW - Height z-score KW - kindergarten children KW - secular trend KW - strategic growth adjustment KW - social signal Y1 - 2017 U6 - https://doi.org/10.1127/anthranz/2017/0708 SN - 0003-5548 VL - 74 IS - 2 SP - 109 EP - 112 PB - Schweizerbart science publishers CY - Stuttgart ER - TY - JOUR A1 - Yarman, Aysu A1 - Scheller, Frieder W. T1 - How reliable is the electrochemical readout of MIP sensors? JF - Sensors N2 - Electrochemical methods offer the simple characterization of the synthesis of molecularly imprinted polymers (MIPs) and the readouts of target binding. The binding of electroinactive analytes can be detected indirectly by their modulating effect on the diffusional permeability of a redox marker through thin MIP films. However, this process generates an overall signal, which may include nonspecific interactions with the nonimprinted surface and adsorption at the electrode surface in addition to (specific) binding to the cavities. Redox-active low-molecular-weight targets and metalloproteins enable a more specific direct quantification of their binding to MIPs by measuring the faradaic current. The in situ characterization of enzymes, MIP-based mimics of redox enzymes or enzyme-labeled targets, is based on the indication of an electroactive product. This approach allows the determination of both the activity of the bio(mimetic) catalyst and of the substrate concentration. KW - molecularly imprinted polymers KW - electropolymerization KW - direct electron KW - transfer KW - catalysis KW - redox marker KW - gate effect Y1 - 2020 U6 - https://doi.org/10.3390/s20092677 SN - 1424-8220 VL - 20 IS - 9 PB - MDPI CY - Basel ER - TY - JOUR A1 - Groth, Detlef T1 - Modeling a secular trend by Monte Carlo simulation of height biased migration in a spatial network JF - Anthropologischer Anzeiger : journal of biological and clinical anthropology ; Mitteilungsorgan der Gesellschaft für Anthropologie N2 - Background: In a recent Monte Carlo simulation, the clustering of body height of Swiss military conscripts within a spatial network with characteristic features of the natural Swiss geography was investigated. In this study I examined the effect of migration of tall individuals into network hubs on the dynamics of body height within the whole spatial network. The aim of this study was to simulate height trends. Material and methods: Three networks were used for modeling, a regular rectangular fishing net like network, a real world example based on the geographic map of Switzerland, and a random network. All networks contained between 144 and 148 districts and between 265-307 road connections. Around 100,000 agents were initially released with average height of 170 cm, and height standard deviation of 6.5 cm. The simulation was started with the a priori assumption that height variation within a district is limited and also depends on height of neighboring districts (community effect on height). In addition to a neighborhood influence factor, which simulates a community effect, body height dependent migration of conscripts between adjacent districts in each Monte Carlo simulation was used to re-calculate next generation body heights. In order to determine the direction of migration for taller individuals, various centrality measures for the evaluation of district importance within the spatial network were applied. Taller individuals were favored to migrate more into network hubs, backward migration using the same number of individuals was random, not biased towards body height. Network hubs were defined by the importance of a district within the spatial network. The importance of a district was evaluated by various centrality measures. In the null model there were no road connections, height information could not be delivered between the districts. Results: Due to the favored migration of tall individuals into network hubs, average body height of the hubs, and later, of the whole network increased by up to 0.1 cm per iteration depending on the network model. The general increase in height within the network depended on connectedness and on the amount of height information that was exchanged between neighboring districts. If higher amounts of neighborhood height information were exchanged, the general increase in height within the network was large (strong secular trend). The trend in the homogeneous fishnet like network was lowest, the trend in the random network was highest. Yet, some network properties, such as the heteroscedasticity and autocorrelations of the migration simulation models differed greatly from the natural features observed in Swiss military conscript networks. Autocorrelations of district heights for instance, were much higher in the migration models. Conclusion: This study confirmed that secular height trends can be modeled by preferred migration of tall individuals into network hubs. However, basic network properties of the migration simulation models differed greatly from the natural features observed in Swiss military conscripts. Similar network-based data from other countries should be explored to better investigate height trends with Monte Carlo migration approach. KW - secular trend KW - body height KW - simulation KW - community effect KW - Monte Carlo method KW - network Y1 - 2017 U6 - https://doi.org/10.1127/anthranz/2017/0703 SN - 0003-5548 SN - 2363-7099 VL - 74 IS - 1 SP - 81 EP - 88 PB - Schweizerbart CY - Stuttgart ER - TY - JOUR A1 - Bents, Dominik A1 - Rybak, Alexander A1 - Groth, Detlef T1 - Spatial conscript body height correlation of Norwegian districts in the 19th century JF - Anthropologischer Anzeiger : journal of biological and clinical anthropology ; Mitteilungsorgan der Gesellschaft für Anthropologie N2 - Background: We investigated height of Norwegian conscripts in view of the hypothesis of a "community effect on height" using autocorrelation analysis of district heights within a time-span of 20 years at the end of the 19th century and correlations between neighboring districts at this time. Material and methods: After digitalizing available body height data of Norwegian draftees in 1877-1878, 1880 (averaged as 1878), and 1895-1897 (averaged as 1896) we calculated the magnitude of autocorrelation of body height within the same municipality at different time points. Furthermore, we generated three different neighborhood networks, (1) based on Euclidean distances, (2) a minimum spanning tree build on those distances, (3) a network founded on real world road connections. The networks were used to determine the correlation between body height of neighboring districts depending on the number of edges required to connect two municipalities. Results: The autocorrelation value for body heights was around r = 0.5 (for all p < 0.001) in the years 1878 and 1896. The correlation between neighboring districts varied in the Euclidean distance based network between 0.47 and 0.27 approximately for both years in a sorted order, descending from nearest (0-50 km) to farthest (150-200 km, for all p < 0.001). First order neighbors in the minimum spanning tree network correlation was 0.36 in 1878 and 0.42 in 1896 (for all p < 0.001). The values of neighbor correlation in the road connection based network ranged in 1878 from 0.42 (first order neighbors) to 0.17 (forth order neighbors, for all p < 0.01) and in 1896 from 0.46 (first order neighbors) to 0.12 (forth order neighbors, for all p < 0.05). Conclusion: This initial study of Norwegian conscript height data from the 19th century showed significant medium sized effects for the within district autocorrelation between 1878 and 1896 as well as medium neighborhood correlation, slightly lower in comparison to a recent study regarding Swiss conscripts. Digitalizing more data from other years in this and later time spans as well as using older road and ship connections instead of the actual road data might stabilize and improve those findings. KW - body height KW - correlation KW - Norway KW - conscripts KW - community effect on height Y1 - 2017 U6 - https://doi.org/10.1127/anthranz/2017/0700 SN - 0003-5548 SN - 2363-7099 VL - 74 IS - 1 SP - 65 EP - 69 PB - Schweizerbart CY - Stuttgart ER - TY - JOUR A1 - Weithoff, Guntram A1 - Bell, Elanor Margaret T1 - Complex Trophic Interactions in an Acidophilic Microbial Community JF - Microorganisms N2 - Extreme habitats often harbor specific communities that differ substantially from non-extreme habitats. In many cases, these communities are characterized by archaea, bacteria and protists, whereas the number of species of metazoa and higher plants is relatively low. In extremely acidic habitats, mostly prokaryotes and protists thrive, and only very few metazoa thrive, for example, rotifers. Since many studies have investigated the physiology and ecology of individual species, there is still a gap in research on direct, trophic interactions among extremophiles. To fill this gap, we experimentally studied the trophic interactions between a predatory protist (Actinophrys sol, Heliozoa) and its prey, the rotifers Elosa woralli and Cephalodella sp., the ciliate Urosomoida sp. and the mixotrophic protist Chlamydomonas acidophila (a green phytoflagellate, Chlorophyta). We found substantial predation pressure on all animal prey. High densities of Chlamydomonas acidophila reduced the predation impact on the rotifers by interfering with the feeding behaviour of A. sol. These trophic relations represent a natural case of intraguild predation, with Chlamydomonas acidophila being the common prey and the rotifers/ciliate and A. sol being the intraguild prey and predator, respectively. We further studied this intraguild predation along a resource gradient using Cephalodella sp. as the intraguild prey. The interactions among the three species led to an increase in relative rotifer abundance with increasing resource (Chlamydomonas) densities. By applying a series of laboratory experiments, we revealed the complexity of trophic interactions within a natural extremophilic community. KW - acid mine drainage KW - extremophiles KW - food web KW - heliozoa KW - intraguild predation KW - mining lakes KW - Rotifera Y1 - 2022 U6 - https://doi.org/10.3390/microorganisms10071340 SN - 2076-2607 VL - 10 SP - 1 EP - 10 PB - MDPI CY - Basel, Schweiz ET - 7 ER - TY - JOUR A1 - Garrido, Claudia A1 - Leimkühler, Silke T1 - The inactivation of human aldehyde oxidase 1 by hydrogen peroxide and superoxide JF - Drug metabolism and disposition / American Society for Pharmacology and Experimental Therapeutics N2 - Mammalian aldehyde oxidases (AOX) are molybdo-flavoenzymes of pharmacological and pathophysiologic relevance that are involved in phase I drug metabolism and, as a product of their enzymatic activity, are also involved in the generation of reactive oxygen species. So far, the physiologic role of aldehyde oxidase 1 in the human body remains unknown. The human enzyme hAOX1 is characterized by a broad substrate specificity, oxidizing aromatic/aliphatic aldehydes into their corresponding carboxylic acids, and hydroxylating various heteroaromatic rings. The enzyme uses oxygen as terminal electron acceptor to produce hydrogen peroxide and superoxide during turnover. Since hAOX1 and, in particular, some natural variants produce not only H2O2 but also high amounts of superoxide, we investigated the effect of both ROS molecules on the enzymatic activity of hAOX1 in more detail. We compared hAOX1 to the high-O-2(.-)-producing natural variant L438V for their time-dependent inactivation with H2O2/O-2(.-) during substrate turnover. We show that the inactivation of the hAOX1 wild-type enzyme is mainly based on the production of hydrogen peroxide, whereas for the variant L438V, both hydrogen peroxide and superoxide contribute to the time-dependent inactivation of the enzyme during turnover. Further, the level of inactivation was revealed to be substrate-dependent: using substrates with higher turnover numbers resulted in a faster inactivation of the enzymes. Analysis of the inactivation site of the enzyme identified a loss of the terminal sulfido ligand at the molybdenum active site by the produced ROS during turnover. Y1 - 2021 U6 - https://doi.org/10.1124/dmd.121.000549 SN - 1521-009X SN - 0090-9556 VL - 49 IS - 9 SP - 729 EP - 735 PB - American Society for Pharmacology and Experimental Therapeutics CY - Bethesda ER - TY - JOUR A1 - Dolotovskaya, Sofya A1 - Bordallo, Juan Torroba A1 - Haus, Tanja A1 - Noll, Angela A1 - Hofreiter, Michael A1 - Zinner, Dietmar A1 - Roos, Christian T1 - Comparing mitogenomic timetrees for two African savannah primate genera (Chlorocebus and Papio) BT - Corrigenda JF - Zoological journal of the Linnean Society Y1 - 2020 U6 - https://doi.org/10.1093/zoolinnean/zlaa026 SN - 0024-4082 SN - 1096-3642 N1 - This is a correction to: Zoological Journal of the Linnean Society. - 181 (2017) 2. - S. 471 – 483, https://doi.org/10.1093/zoolinnean/zlx001 VL - 190 IS - 3 SP - 1071 EP - 1073 PB - Oxford Univ. Press CY - Oxford ER - TY - JOUR A1 - Nickerson, David A1 - Atalag, Koray A1 - de Bono, Bernard A1 - Geiger, Joerg A1 - Goble, Carole A1 - Hollmann, Susanne A1 - Lonien, Joachim A1 - Mueller, Wolfgang A1 - Regierer, Babette A1 - Stanford, Natalie J. A1 - Golebiewski, Martin A1 - Hunter, Peter T1 - The Human Physiome: how standards, software and innovative service infrastructures are providing the building blocks to make it achievable JF - Interface focus N2 - Reconstructing and understanding the Human Physiome virtually is a complex mathematical problem, and a highly demanding computational challenge. Mathematical models spanning from the molecular level through to whole populations of individuals must be integrated, then personalized. This requires interoperability with multiple disparate and geographically separated data sources, and myriad computational software tools. Extracting and producing knowledge from such sources, even when the databases and software are readily available, is a challenging task. Despite the difficulties, researchers must frequently perform these tasks so that available knowledge can be continually integrated into the common framework required to realize the Human Physiome. Software and infrastructures that support the communities that generate these, together with their underlying standards to format, describe and interlink the corresponding data and computer models, are pivotal to the Human Physiome being realized. They provide the foundations for integrating, exchanging and re-using data and models efficiently, and correctly, while also supporting the dissemination of growing knowledge in these forms. In this paper, we explore the standards, software tooling, repositories and infrastructures that support this work, and detail what makes them vital to realizing the Human Physiome. KW - Human Physiome KW - standards KW - repositories KW - service infrastructure KW - reproducible science KW - managing big data Y1 - 2016 U6 - https://doi.org/10.1098/rsfs.2015.0103 SN - 2042-8898 SN - 2042-8901 VL - 6 SP - 57 EP - 61 PB - Royal Society CY - London ER - TY - JOUR A1 - Zimmermann, P. A1 - Regierer, Babette A1 - Kossmann, Jens A1 - Frossard, Emmanuel A1 - Amrhein, Nikolaus A1 - Bucher, Matthias T1 - Differential expression of three purple acid phosphatases from potato N2 - Three cDNAs encoding purple acid phosphatase (PAP) were cloned from potato (Solanum tuberosum L. cv. Desiree) and expression of the corresponding genes was characterised. StPAP1 encodes a low-molecular weight PAP clustering with mammalian, cyanobacterial, and other plant PAPs. It was highly expressed in stem and root and its expression did not change in response to phosphorus (P) deprivation. StIPAP2 and StPAP3 code for high-molecular weight PAPs typical for plants. Corresponding gene expression was shown to be responsive to the level of P supply, with transcripts of StPAP2 and StPAP3 being most abundant in P-deprived roots or both stem and roots, respectively. Root colonisation by arbuscular mycorrhizal fungi had no effect on the expression of any of the three PAP genes. StIPAP1 mRNA is easily detectable along the root axis, including root hairs, but is barely detectable in root tips. In contrast, both StPAP2 and StPAP3 transcripts are abundant along the root axis, but absent in root hairs, and are most abundant in the root tip. All three PAPs described contain a predicted N-terminal secretion signal and could play a role in extracellular P scavenging, P mobilisation from the rhizosphere, or cell wall regeneration Y1 - 2004 SN - 1435-8603 ER - TY - JOUR A1 - Badalyan, Artavazd A1 - Dierich, Marlen A1 - Stiba, Konstanze A1 - Schwuchow, Viola A1 - Leimkühler, Silke A1 - Wollenberger, Ulla T1 - Electrical wiring of the aldehyde oxidoreductase PaoABC with a polymer containing osmium redox centers BT - biosensors for benzaldehyde and GABA JF - Biosensors N2 - Biosensors for the detection of benzaldehyde and g-aminobutyric acid (GABA) are reported using aldehyde oxidoreductase PaoABC from Escherichia coli immobilized in a polymer containing bound low potential osmium redox complexes. The electrically connected enzyme already electrooxidizes benzaldehyde at potentials below −0.15 V (vs. Ag|AgCl, 1 M KCl). The pH-dependence of benzaldehyde oxidation can be strongly influenced by the ionic strength. The effect is similar with the soluble osmium redox complex and therefore indicates a clear electrostatic effect on the bioelectrocatalytic efficiency of PaoABC in the osmium containing redox polymer. At lower ionic strength, the pH-optimum is high and can be switched to low pH-values at high ionic strength. This offers biosensing at high and low pH-values. A “reagentless” biosensor has been formed with enzyme wired onto a screen-printed electrode in a flow cell device. The response time to addition of benzaldehyde is 30 s, and the measuring range is between 10–150 µM and the detection limit of 5 µM (signal to noise ratio 3:1) of benzaldehyde. The relative standard deviation in a series (n = 13) for 200 µM benzaldehyde is 1.9%. For the biosensor, a response to succinic semialdehyde was also identified. Based on this response and the ability to work at high pH a biosensor for GABA is proposed by coimmobilizing GABA-aminotransferase (GABA-T) and PaoABC in the osmium containing redox polymer. KW - redox polymer KW - aldehyde oxidoreductase KW - ionic strength KW - benzaldehyde KW - GABA KW - biosensor Y1 - 2014 U6 - https://doi.org/10.3390/bios4040403 VL - 4 IS - 4 SP - 403 EP - 421 PB - MDPI CY - Basel ER - TY - JOUR A1 - Sperfeld, Erik A1 - Schmidtke, Andrea A1 - Gaedke, Ursula A1 - Weithoff, Guntram T1 - Productivity, herbivory, and species traits rather than diversity influence invasibility of experimental phytoplankton communities N2 - Biological invasions are a major threat to natural biodiversity; hence, understanding the mechanisms underlying invasibility (i.e., the susceptibility of a community to invasions by new species) is crucial. Invasibility of a resident community may be affected by a complex but hitherto hardly understood interplay of (1) productivity of the habitat, (2) diversity, (3) herbivory, and (4) the characteristics of both invasive and resident species. Using experimental phytoplankton microcosms, we investigated the effect of nutrient supply and species diversity on the invasibility of resident communities for two functionally different invaders in the presence or absence of an herbivore. With increasing nutrient supply, increased herbivore abundance indicated enhanced phytoplankton biomass production, and the invasion success of both invaders showed a unimodal pattern. At low nutrient supply (i.e., low influence of herbivory), the invasibility depended mainly on the competitive abilities of the invaders, whereas at high nutrient supply, the susceptibility to herbivory dominated. This resulted in different optimum nutrient levels for invasion success of the two species due to their individual functional traits. To test the effect of diversity on invasibility, a species richness gradient was generated by random selection from a resident species pool at an intermediate nutrient level. Invasibility was not affected by species richness; instead, it was driven by the functional traits of the resident and/or invasive species mediated by herbivore density. Overall, herbivory was the driving factor for invasibility of phytoplankton communities, which implies that other factors affecting the intensity of herbivory (e.g., productivity or edibility of primary producers) indirectly influence invasions. Y1 - 2010 UR - http://springerlink.metapress.com/content/100458/ U6 - https://doi.org/10.1007/s00442-010-1594-4 SN - 0029-8549 ER - TY - THES A1 - Sperfeld, Erik T1 - Effects of temperature and co-limiting nutritional components on life history traits of Daphnia magna and its biochemical composition Y1 - 2011 CY - Potsdam ER - TY - JOUR A1 - Ceulemans, Ruben A1 - Guill, Christian A1 - Gaedke, Ursula T1 - Top predators govern multitrophic diversity effects in tritrophic food webs JF - Ecology : a publication of the Ecological Society of America N2 - It is well known that functional diversity strongly affects ecosystem functioning. However, even in rather simple model communities consisting of only two or, at best, three trophic levels, the relationship between multitrophic functional diversity and ecosystem functioning appears difficult to generalize, because of its high contextuality. In this study, we considered several differently structured tritrophic food webs, in which the amount of functional diversity was varied independently on each trophic level. To achieve generalizable results, largely independent of parametrization, we examined the outcomes of 128,000 parameter combinations sampled from ecologically plausible intervals, with each tested for 200 randomly sampled initial conditions. Analysis of our data was done by training a random forest model. This method enables the identification of complex patterns in the data through partial dependence graphs, and the comparison of the relative influence of model parameters, including the degree of diversity, on food-web properties. We found that bottom-up and top-down effects cascade simultaneously throughout the food web, intimately linking the effects of functional diversity of any trophic level to the amount of diversity of other trophic levels, which may explain the difficulty in unifying results from previous studies. Strikingly, only with high diversity throughout the whole food web, different interactions synergize to ensure efficient exploitation of the available nutrients and efficient biomass transfer to higher trophic levels, ultimately leading to a high biomass and production on the top level. The temporal variation of biomass showed a more complex pattern with increasing multitrophic diversity: while the system initially became less variable, eventually the temporal variation rose again because of the increasingly complex dynamical patterns. Importantly, top predator diversity and food-web parameters affecting the top trophic level were of highest importance to determine the biomass and temporal variability of any trophic level. Overall, our study reveals that the mechanisms by which diversity influences ecosystem functioning are affected by every part of the food web, hampering the extrapolation of insights from simple monotrophic or bitrophic systems to complex natural food webs. KW - food-web efficiency KW - functional diversity KW - machine learning KW - nutrient KW - exploitation KW - production KW - random forest KW - temporal variability KW - top KW - predator KW - trait diversity Y1 - 2021 U6 - https://doi.org/10.1002/ecy.3379 SN - 0012-9658 SN - 1939-9170 VL - 102 IS - 7 PB - Wiley CY - Hoboken ER - TY - JOUR A1 - Mitic, Kristina A1 - Grafe, Marianne A1 - Batsios, Petros A1 - Meyer, Irene T1 - Partial Disassembly of the Nuclear Pore Complex Proteins during Semi-Closed Mitosis in Dictyostelium discoideum JF - Cells N2 - Dictyostelium cells undergo a semi-closed mitosis, during which the nuclear envelope (NE) persists; however, free diffusion between the cytoplasm and the nucleus takes place. To permit the formation of the mitotic spindle, the nuclear envelope must be permeabilized in order to allow diffusion of tubulin dimers and spindle assembly factors into the nucleus. In Aspergillus, free diffusion of proteins between the cytoplasm and the nucleus is achieved by a partial disassembly of the nuclear pore complexes (NPCs) prior to spindle assembly. In order to determine whether this is also the case in Dictyostelium, we analysed components of the NPC by immunofluorescence microscopy and live cell imaging and studied their behaviour during interphase and mitosis. We observed that the NPCs are absent from the contact area of the nucleoli and that some nucleoporins also localize to the centrosome and the spindle poles. In addition, we could show that, during mitosis, the central FG protein NUP62, two inner ring components and Gle1 depart from the NPCs, while all other tested NUPs remained at the NE. This leads to the conclusion that indeed a partial disassembly of the NPCs takes place, which contributes to permeabilisation of the NE during semi-closed mitosis. KW - nuclear pore complex KW - nucleoporins KW - semi-closed mitosis KW - centrosome KW - Dictyostelium Y1 - 2021 U6 - https://doi.org/10.3390/cells11030407 SN - 2073-4409 VL - 11 IS - 3 PB - MDPI CY - Basel ER - TY - JOUR A1 - Grafe, Marianne A1 - Hofmann, Phillip A1 - Batsios, Petros A1 - Meyer, Irene A1 - Gräf, Ralph T1 - In vivo assembly of a Dictyostelium lamin mutant induced by light, mechanical stress, and pH JF - Cells : open access journal N2 - We expressedDictyosteliumlamin (NE81) lacking both a functional nuclear localization signal and a CAAX-box for C-terminal lipid modification. This lamin mutant assembled into supramolecular, three-dimensional clusters in the cytosol that disassembled at the onset of mitosis and re-assembled in late telophase, thus mimicking the behavior of the endogenous protein. As disassembly is regulated by CDK1-mediated phosphorylation at serine 122, we generated a phosphomimetic S122E mutant called GFP-NE81-S122E-Delta NLS Delta CLIM. Surprisingly, during imaging, the fusion protein assembled into cytosolic clusters, similar to the protein lacking the phosphomimetic mutation. Clusters disassembled again in the darkness. Assembly could be induced with blue but not green or near ultraviolet light, and it was independent of the fusion tag. Assembly similarly occurred upon cell flattening. Earlier reports and own observations suggested that both blue light and cell flattening could result in a decrease of intracellular pH. Indeed, keeping the cells at low pH also reversibly induced cluster formation. Our results indicate that lamin assembly can be induced by various stress factors and that these are transduced via intracellular acidification. Although these effects have been shown in a phosphomimetic CDK1 mutant of theDictyosteliumlamin, they are likely relevant also for wild-type lamin. KW - lamin KW - NE81 KW - Dictyostelium KW - nuclear envelope KW - nuclear lamina Y1 - 2020 U6 - https://doi.org/10.3390/cells9081834 SN - 2073-4409 VL - 9 IS - 8 PB - MDPI CY - Basel ER - TY - JOUR A1 - Neumann, Bettina A1 - Wollenberger, Ulla T1 - Electrochemical biosensors employing natural and artificial heme peroxidases on semiconductors JF - Sensors N2 - Heme peroxidases are widely used as biological recognition elements in electrochemical biosensors for hydrogen peroxide and phenolic compounds. Various nature-derived and fully synthetic heme peroxidase mimics have been designed and their potential for replacing the natural enzymes in biosensors has been investigated. The use of semiconducting materials as transducers can thereby offer new opportunities with respect to catalyst immobilization, reaction stimulation, or read-out. This review focuses on approaches for the construction of electrochemical biosensors employing natural heme peroxidases as well as various mimics immobilized on semiconducting electrode surfaces. It will outline important advances made so far as well as the novel applications resulting thereof. KW - electrochemical biosensors KW - heme KW - peroxidases KW - semiconductors KW - peroxidase mimics Y1 - 2020 U6 - https://doi.org/10.3390/s20133692 SN - 1424-8220 VL - 20 IS - 13 PB - MDPI CY - Basel ER - TY - JOUR A1 - Sauer, Michael A1 - Grebe, Markus T1 - Plant cell biology BT - PIN polarity maintained JF - Current biology : CB N2 - PIN-FORMED (PIN) polar protein localization directs transport of the growth and developmental regulator auxin in plants. Once established after cytokinesis, PIN polarity requires maintenance. Now, direct interactions between PIN, MAB4/MEL and PID proteins suggest self-reinforced maintenance of PIN polarity through limiting lateral diffusion. Y1 - 2021 U6 - https://doi.org/10.1016/j.cub.2021.03.070 SN - 0960-9822 SN - 1879-0445 VL - 31 IS - 9 SP - R449 EP - R451 PB - Cell Press CY - Cambridge ER - TY - JOUR A1 - van Velzen, Ellen T1 - Predator coexistence through emergent fitness equalization JF - Ecology : a publication of the Ecological Society of America N2 - The competitive exclusion principle is one of the oldest ideas in ecology and states that without additional self-limitation two predators cannot coexist on a single prey. The search for mechanisms allowing coexistence despite this has identified niche differentiation between predators as crucial: without this, coexistence requires the predators to have exactly the same R* values, which is considered impossible. However, this reasoning misses a critical point: predators' R* values are not static properties, but affected by defensive traits of their prey, which in turn can adapt in response to changes in predator densities. Here I show that this feedback between defense and predator dynamics enables stable predator coexistence without ecological niche differentiation. Instead, the mechanism driving coexistence is that prey adaptation causes defense to converge to the value where both predators have equal R* values ("fitness equalization"). This result is highly general, independent of specific model details, and applies to both rapid defense evolution and inducible defenses. It demonstrates the importance of considering long-standing ecological questions from an eco-evolutionary viewpoint, and showcases how the effects of adaptation can cascade through communities, driving diversity on higher trophic levels. These insights offer an important new perspective on coexistence theory. KW - coexistence KW - competition KW - competitive exclusion KW - defense KW - eco-evolutionary feedbacks KW - emergent facilitation KW - predator KW - prey KW - dynamics Y1 - 2020 U6 - https://doi.org/10.1002/ecy.2995 SN - 0012-9658 SN - 1939-9170 VL - 101 IS - 5 PB - Wiley CY - Hoboken ER - TY - CHAP A1 - Neumann-Schaal, M. A1 - Messerschmidt, Katrin A1 - Grenz, N. A1 - Micheel, Burkhard A1 - Heilmann, K. T1 - Use of antibody gene library for the isolation of specific single chain antibodies by ampicillin-antigen conjugates T2 - Immunology : an official journal of the British Society for Immunology Y1 - 2012 SN - 0019-2805 VL - 137 IS - 3 SP - 661 EP - 661 PB - Wiley-Blackwell CY - Hoboken ER -