TY - JOUR A1 - Berry, Scott A1 - Rosa, Stefanie A1 - Howard, Martin A1 - Buhler, Marc A1 - Dean, Caroline T1 - Disruption of an RNA-binding hinge region abolishes LHP1-mediated epigenetic repression JF - Genes & Development N2 - Epigenetic maintenance of gene repression is essential for development. Polycomb complexes are central to this memory, but many aspects of the underlying mechanism remain unclear. LIKE HETEROCHROMATIN PROTEIN 1 (LHP1) binds Polycomb-deposited H3K27me3 and is required for repression of many Polycomb target genes in Arabidopsis. Here we show that LHP1 binds RNA in vitro through the intrinsically disordered hinge region. By independently perturbing the RNA-binding hinge region and H3K27me3 (trimethylation of histone H3 at Lys27) recognition, we found that both facilitate LHP1 localization and H3K27me3 maintenance. Disruption of the RNAbinding hinge region also prevented formation of subnuclear foci, structures potentially important for epigenetic repression. KW - chromatin KW - epigenetics KW - plant biology KW - Polycomb KW - RNA Y1 - 2017 U6 - https://doi.org/10.1101/gad.305227.117 SN - 0890-9369 SN - 1549-5477 VL - 31 SP - 2115 EP - 2120 PB - Cold Spring Harbor Laboratory Press CY - Cold Spring Harbor, NY ER - TY - JOUR A1 - Endesfelder, Stefanie A1 - Weichelt, Ulrike A1 - Strauß, Evelyn A1 - Schlör, Anja A1 - Sifringer, Marco A1 - Scheuer, Till A1 - Bührer, Christoph A1 - Schmitz, Thomas T1 - Neuroprotection by caffeine in hyperoxia-induced neonatal brain injury JF - International journal of molecular sciences N2 - Sequelae of prematurity triggered by oxidative stress and free radical-mediated tissue damage have coined the term “oxygen radical disease of prematurity”. Caffeine, a potent free radical scavenger and adenosine receptor antagonist, reduces rates of brain damage in preterm infants. In the present study, we investigated the effects of caffeine on oxidative stress markers, anti-oxidative response, inflammation, redox-sensitive transcription factors, apoptosis, and extracellular matrix following the induction of hyperoxia in neonatal rats. The brain of a rat pups at postnatal Day 6 (P6) corresponds to that of a human fetal brain at 28–32 weeks gestation and the neonatal rat is an ideal model in which to investigate effects of oxidative stress and neuroprotection of caffeine on the developing brain. Six-day-old Wistar rats were pre-treated with caffeine and exposed to 80% oxygen for 24 and 48 h. Caffeine reduced oxidative stress marker (heme oxygenase-1, lipid peroxidation, hydrogen peroxide, and glutamate-cysteine ligase catalytic subunit (GCLC)), promoted anti-oxidative response (superoxide dismutase, peroxiredoxin 1, and sulfiredoxin 1), down-regulated pro-inflammatory cytokines, modulated redox-sensitive transcription factor expression (Nrf2/Keap1, and NFκB), reduced pro-apoptotic effectors (poly (ADP-ribose) polymerase-1 (PARP-1), apoptosis inducing factor (AIF), and caspase-3), and diminished extracellular matrix degeneration (matrix metalloproteinases (MMP) 2, and inhibitor of metalloproteinase (TIMP) 1/2). Our study affirms that caffeine is a pleiotropic neuroprotective drug in the developing brain due to its anti-oxidant, anti-inflammatory, and anti-apoptotic properties. KW - anti-oxidative response KW - caffeine KW - hyperoxia KW - oxidative stress KW - preterm infants KW - developing brain Y1 - 2017 U6 - https://doi.org/10.3390/ijms18010187 SN - 1422-0067 SN - 1661-6596 VL - 18 PB - Molecular Diversity Preservation International CY - Basel 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 - Yarman, Aysu A1 - Jetzschmann, Katharina J. A1 - Neumann, Bettina A1 - Zhang, Xiaorong A1 - Wollenberger, Ulla A1 - Cordin, Aude A1 - Haupt, Karsten A1 - Scheller, Frieder W. T1 - Enzymes as Tools in MIP-Sensors JF - Chemosensors N2 - Molecularly imprinted polymers (MIPs) have the potential to complement antibodies in bioanalysis, are more stable under harsh conditions, and are potentially cheaper to produce. However, the affinity and especially the selectivity of MIPs are in general lower than those of their biological pendants. Enzymes are useful tools for the preparation of MIPs for both low and high-molecular weight targets: As a green alternative to the well-established methods of chemical polymerization, enzyme-initiated polymerization has been introduced and the removal of protein templates by proteases has been successfully applied. Furthermore, MIPs have been coupled with enzymes in order to enhance the analytical performance of biomimetic sensors: Enzymes have been used in MIP-sensors as tracers for the generation and amplification of the measuring signal. In addition, enzymatic pretreatment of an analyte can extend the analyte spectrum and eliminate interferences. KW - enzymatic MIP synthesis KW - template digestion KW - enzyme tracer KW - enzymatic analyte conversion KW - molecularly imprinted polymers Y1 - 2017 U6 - https://doi.org/10.3390/chemosensors5020011 SN - 2227-9040 VL - 5 PB - MDPI CY - Basel ER - TY - JOUR A1 - Thomas, Jessica E. A1 - Carvalho, Gary R. A1 - Haile, James A1 - Martin, Michael D. A1 - Castruita, Jose A. Samaniego A1 - Niemann, Jonas A1 - Sinding, Mikkel-Holger S. A1 - Sandoval-Velasco, Marcela A1 - Rawlence, Nicolas J. A1 - Fuller, Errol A1 - Fjeldsa, Jon A1 - Hofreiter, Michael A1 - Stewart, John R. A1 - Gilbert, M. Thomas P. A1 - Knapp, Michael T1 - An ‛Aukward’ tale BT - a genetic approach to discover the whereabouts of the Last Great Auks JF - Genes N2 - One hundred and seventy-three years ago, the last two Great Auks, Pinguinus impennis, ever reliably seen were killed. Their internal organs can be found in the collections of the Natural History Museum of Denmark, but the location of their skins has remained a mystery. In 1999, Great Auk expert Errol Fuller proposed a list of five potential candidate skins in museums around the world. Here we take a palaeogenomic approach to test which—if any—of Fuller’s candidate skins likely belong to either of the two birds. Using mitochondrial genomes from the five candidate birds (housed in museums in Bremen, Brussels, Kiel, Los Angeles, and Oldenburg) and the organs of the last two known individuals, we partially solve the mystery that has been on Great Auk scholars’ minds for generations and make new suggestions as to the whereabouts of the still-missing skin from these two birds. KW - ancient DNA KW - extinct birds KW - mitochondrial genome KW - museum specimens KW - palaeogenomics Y1 - 2017 U6 - https://doi.org/10.3390/genes8060164 SN - 2073-4425 VL - 8 IS - 6 SP - 164 PB - MDPI CY - Basel ER - TY - JOUR A1 - Gisder, Sebastian A1 - Schüler, Vivian A1 - Horchler, Lennart L. A1 - Groth, Detlef A1 - Genersch, Elke T1 - Long-Term Temporal Trends of Nosema spp. Infection Prevalence in Northeast Germany BT - Continuous Spread of Nosema ceranae, an Emerging Pathogen of Honey Bees (Apis mellifera), but No General Replacement of Nosema apis JF - Frontiers in cellular and infection microbiology N2 - The Western honey bee (Apis mellifera) is widely used as commercial pollinator in worldwide agriculture and, therefore, plays an important role in global food security. Among the parasites and pathogens threatening health and survival of honey bees are two species of microsporidia, Nosema apis and Nosema ceranae. Nosema ceranae is considered an emerging pathogen of the Western honey bee. Reports on the spread of N. ceranae suggested that this presumably highly virulent species is replacing its more benign congener N. apis in the global A. mellifera population. We here present a 12 year longitudinal cohort study on the prevalence of N. apis and N. ceranae in Northeast Germany. Between 2005 and 2016, a cohort of about 230 honey bee colonies originating from 23 apiaries was sampled twice a year (spring and autumn) resulting in a total of 5,600 bee samples which were subjected to microscopic and molecular analysis for determining the presence of infections with N. apis or/and N. ceranae. Throughout the entire study period, both N. apis- and N. ceranae-infections could be diagnosed within the cohort. Logistic regression analysis of the prevalence data demonstrated a significant increase of N. ceranae-infections over the last 12 years, both in autumn (reflecting the development during the summer) and in spring (reflecting the development over winter) samples. Cell culture experiments confirmed that N. ceranae has a higher proliferative potential than N. apis at 27. and 33 degrees C potentially explaining the increase in N. ceranae prevalence during summer. In autumn, characterized by generally low infection prevalence, this increase was accompanied by a significant decrease in N. apis- infection prevalence. In contrast, in spring, the season with a higher prevalence of infection, no significant decrease of N. apis infections despite a significant increase in N. ceranae infections could be observed. Therefore, our data do not support a general advantage of N. ceranae over N. apis and an overall replacement of N. apis by N. ceranae in the studied honey bee population. KW - honey bee KW - Apis mellifera KW - Nosema spp. KW - epidemiology KW - replacement Y1 - 2017 U6 - https://doi.org/10.3389/fcimb.2017.00301 SN - 2235-2988 VL - 7 PB - Frontiers Research Foundation CY - Lausanne ER - TY - JOUR A1 - Paragas, Erickson M. A1 - Humphreys, Sara C. A1 - Min, Joshua A1 - Joswig-Jones, Carolyn A. A1 - Leimkühler, Silke A1 - Jones, Jeffrey P. T1 - ecoAO BT - a simple system for the study of human aldehyde oxidases role in drug metabolism JF - ACS OMEGA N2 - Although aldehyde oxidase (AO) is an important hepatic drug-metabolizing enzyme, it remains understudied and is consequently often overlooked in preclinical studies, an oversight that has resulted in the failure of multiple clinical trials. AO’s preclusion to investigation stems from the following: (1) difficulties synthesizing metabolic standards due to the chemospecificity and regiospecificity of the enzyme and (2) significant inherent variability across existing in vitro systems including liver cytosol, S9 fractions, and primary hepatocytes, which lack specificity and generate discordant expression and activity profiles. Here, we describe a practical bacterial biotransformation system, ecoAO, addressing both issues simultaneously. ecoAO is a cell paste of MoCo-producing Escherichia coli strain TP1017 expressing human AO. It exhibits specific activity toward known substrates, zoniporide, 4-trans-(N,N-dimethylamino)cinnamaldehyde, O6-benzylguanine, and zaleplon; it also has utility as a biocatalyst, yielding milligram quantities of synthetically challenging metabolite standards such as 2-oxo-zoniporide. Moreover, ecoAO enables routine determination of kcat and V/K, which are essential parameters for accurate in vivo clearance predictions. Furthermore, ecoAO has potential as a preclinical in vitro screening tool for AO activity, as demonstrated by its metabolism of 3-aminoquinoline, a previously uncharacterized substrate. ecoAO promises to provide easy access to metabolites with the potential to improve pharmacokinetic clearance predictions and guide drug development. Y1 - 2017 U6 - https://doi.org/10.1021/acsomega.7b01054 SN - 2470-1343 VL - 2 SP - 4820 EP - 4827 PB - American Chemical Society CY - Washington ER - TY - JOUR A1 - Busch, Verena A1 - Klaus, Valentin H. A1 - Penone, Caterina A1 - Schäfer, Deborah A1 - Boch, Steffen A1 - Prati, Daniel A1 - Müller, Jörg A1 - Socher, Stephanie A. A1 - Niinemets, Ülo A1 - Penuelas, Josep A1 - Hölzel, Norbert A1 - Fischer, Markus A1 - Kleinebecker, Till T1 - Nutrient stoichiometry and land use rather than species richness determine plant functional diversity JF - Ecology and evolution N2 - Plant functional traits reflect individual and community ecological strategies. They allow the detection of directional changes in community dynamics and ecosystemic processes, being an additional tool to assess biodiversity than species richness. Analysis of functional patterns in plant communities provides mechanistic insight into biodiversity alterations due to anthropogenic activity. Although studies have consi-dered of either anthropogenic management or nutrient availability on functional traits in temperate grasslands, studies combining effects of both drivers are scarce. Here, we assessed the impacts of management intensity (fertilization, mowing, grazing), nutrient stoichiometry (C, N, P, K), and vegetation composition on community-weighted means (CWMs) and functional diversity (Rao's Q) from seven plant traits in 150 grasslands in three regions in Germany, using data of 6 years. Land use and nutrient stoichiometry accounted for larger proportions of model variance of CWM and Rao's Q than species richness and productivity. Grazing affected all analyzed trait groups; fertilization and mowing only impacted generative traits. Grazing was clearly associated with nutrient retention strategies, that is, investing in durable structures and production of fewer, less variable seed. Phenological variability was increased. Fertilization and mowing decreased seed number/mass variability, indicating competition-related effects. Impacts of nutrient stoichiometry on trait syndromes varied. Nutrient limitation (large N:P, C:N ratios) promoted species with conservative strategies, that is, investment in durable plant structures rather than fast growth, fewer seed, and delayed flowering onset. In contrast to seed mass, leaf-economics variability was reduced under P shortage. Species diversity was positively associated with the variability of generative traits. Synthesis. Here, land use, nutrient availability, species richness, and plant functional strategies have been shown to interact complexly, driving community composition, and vegetation responses to management intensity. We suggest that deeper understanding of underlying mechanisms shaping community assembly and biodiversity will require analyzing all these parameters. KW - biodiversity exploratories KW - fertilization KW - leaf economics KW - mowing KW - nutrient availability KW - nutrient ratios KW - phosphorus KW - plant functional traits KW - plant strategies KW - seed mass Y1 - 2017 U6 - https://doi.org/10.1002/ece3.3609 SN - 2045-7758 VL - 8 IS - 1 SP - 601 EP - 616 PB - Wiley CY - Hoboken ER - TY - JOUR A1 - Lämke, Jörn A1 - Bäurle, Isabel T1 - Epigenetic and chromatin-based mechanisms in environmental stress adaptation and stress memory in plants JF - Genome biology : biology for the post-genomic era N2 - Plants frequently have to weather both biotic and abiotic stressors, and have evolved sophisticated adaptation and defense mechanisms. In recent years, chromatin modifications, nucleosome positioning, and DNA methylation have been recognized as important components in these adaptations. Given their potential epigenetic nature, such modifications may provide a mechanistic basis for a stress memory, enabling plants to respond more efficiently to recurring stress or even to prepare their offspring for potential future assaults. In this review, we discuss both the involvement of chromatin in stress responses and the current evidence on somatic, intergenerational, and transgenerational stress memory. KW - remodeling atpase brahma KW - transcriptional memory KW - DNA methylation KW - transgenerational inheritance KW - acquired thermotolerance KW - Arabidopsis-thaliana KW - gene-expression KW - responses KW - protein KW - defense Y1 - 2017 U6 - https://doi.org/10.1186/s13059-017-1263-6 SN - 1474-760X VL - 18 SP - 8685 EP - 8693 PB - BioMed Central CY - London ER - TY - JOUR A1 - Hentrich, Doreen A1 - Tauer, Klaus A1 - Espanol, Montserrat A1 - Ginebra, Maria-Pau A1 - Taubert, Andreas T1 - EDTA and NTA effectively tune the mineralization of calcium phosphate from bulk aqueous solution JF - Biomimetics N2 - This study describes the effects of nitrilotriacetic acid (NTA) and ethylenediaminotetraacetic acid (EDTA) on themineralization of calciumphosphate from bulk aqueous solution. Mineralization was performed between pH 6 and 9 and with NTA or EDTA concentrations of 0, 5, 10, and 15 mM. X-ray diffraction and infrared spectroscopy show that at low pH, mainly brushite precipitates and at higher pH, mostly hydroxyapatite forms. Both additives alter the morphology of the precipitates. Without additive, brushite precipitates as large plates. With NTA, the morphology changes to an unusual rod-like shape. With EDTA, the edges of the particles are rounded and disk-like particles form. Conductivity and pH measurements suggest that the final products form through several intermediate steps. KW - biomineralization KW - biomimetic mineralization KW - calcium phosphate KW - NTA KW - EDTA KW - precipitation KW - brushite KW - hydroxyapatite Y1 - 2017 U6 - https://doi.org/10.3390/biomimetics2040024 SN - 2313-7673 VL - 2 IS - 4 PB - MDPI CY - Basel ER -