TY - JOUR A1 - Brzezinka, Krzysztof A1 - Altmann, Simone A1 - Czesnick, Hjördis A1 - Nicolas, Philippe A1 - Gorka, Michal A1 - Benke, Eileen A1 - Kabelitz, Tina A1 - Jähne, Felix A1 - Graf, Alexander A1 - Kappel, Christian A1 - Bäurle, Isabel T1 - Arabidopsis FORGETTER1 mediates stress-induced chromatin memory through nucleosome remodeling JF - eLife N2 - Plants as sessile organisms can adapt to environmental stress to mitigate its adverse effects. As part of such adaptation they maintain an active memory of heat stress for several days that promotes a more efficient response to recurring stress. We show that this heat stress memory requires the activity of the FORGETTER1 (FGT1) locus, with fgt1 mutants displaying reduced maintenance of heat-induced gene expression. FGT1 encodes the Arabidopsis thaliana orthologue of Strawberry notch (Sno), and the protein globally associates with the promoter regions of actively expressed genes in a heat-dependent fashion. FGT1 interacts with chromatin remodelers of the SWI/ SNF and ISWI families, which also display reduced heat stress memory. Genomic targets of the BRM remodeler overlap significantly with FGT1 targets. Accordingly, nucleosome dynamics at loci with altered maintenance of heat-induced expression are affected in fgt1. Together, our results suggest that by modulating nucleosome occupancy, FGT1 mediates stress-induced chromatin memory. Y1 - 2016 U6 - https://doi.org/10.7554/eLife.17061 SN - 2050-084X VL - 5 PB - eLife Sciences Publications CY - Cambridge ER - TY - JOUR A1 - Schlägel, Ulrike E. A1 - Lewis, Mark A. T1 - A framework for analyzing the robustness of movement models to variable step discretization JF - Journal of mathematical biology N2 - When sampling animal movement paths, the frequency at which location measurements are attempted is a critical feature for data analysis. Important quantities derived from raw data, e.g. travel distance or sinuosity, can differ largely based on the temporal resolution of the data. Likewise, when movement models are fitted to data, parameter estimates have been demonstrated to vary with sampling rate. Thus, biological statements derived from such analyses can only be made with respect to the resolution of the underlying data, limiting extrapolation of results and comparison between studies. To address this problem, we investigate whether there are models that are robust against changes in temporal resolution. First, we propose a mathematically rigorous framework, in which we formally define robustness as a model property. We then use the framework for a thorough assessment of a range of basic random walk models, in which we also show how robustness relates to other probabilistic concepts. While we found robustness to be a strong condition met by few models only, we suggest a new method to extend models so as to make them robust. Our framework provides a new systematic, mathematically founded approach to the question if, and how, sampling rate of movement paths affects statistical inference. KW - Animal movement KW - Random walk KW - Sampling rate KW - Discretization KW - GPS data KW - Parameter estimation Y1 - 2016 U6 - https://doi.org/10.1007/s00285-016-0969-5 SN - 0303-6812 SN - 1432-1416 VL - 73 SP - 815 EP - 845 PB - Springer CY - Heidelberg ER - TY - JOUR A1 - Schlägel, Ulrike E. A1 - Lewis, Mark A. T1 - Robustness of movement models: can models bridge the gap between temporal scales of data sets and behavioural processes? JF - Journal of mathematical biology KW - Animal movement KW - Sampling rate KW - Resource selection KW - GPS data KW - Parameter estimation KW - Markov model Y1 - 2016 U6 - https://doi.org/10.1007/s00285-016-1005-5 SN - 0303-6812 SN - 1432-1416 VL - 73 SP - 1691 EP - 1726 PB - Springer CY - Heidelberg ER - TY - JOUR A1 - Lamanna, Francesco A1 - Kirschbaum, Frank A1 - Ernst, Anja R. R. A1 - Feulner, Philine G. D. A1 - Mamonekene, Victor A1 - Paul, Christiane A1 - Tiedemann, Ralph T1 - Species delimitation and phylogenetic relationships in a genus of African weakly-electric fishes (Osteoglossiformes, Mormyridae, Campylomormyrus) JF - Molecular phylogenetics and evolution N2 - African weakly-electric fishes (Mormyridae) are able to communicate through species-specific electric signals; this feature might have favoured the evolutionary radiation observed in this family (over 200 species) by acting as an effective pre-zygotic isolation mechanism. In the present study we used mitochondria((cytb) and nuclear (rps7, scn4aa) markers in order to reconstruct a species-phylogeny and identify species boundaries for the genus Campylomormyrus, by applying inference methods based on the multispecies coalescent model. Additionally, we employed 16 microsatellite markers, landmark-based morphometric measurements, and electro-physiological analyses as independent lines of evidence to the results obtained from the sequence data. The results show that groups that are morphologically different are also significantly divergent at the genetic level, whereas morphologically similar groups, displaying dissimilar electric signals, do not show enough genetic diversity to be considered separate species. Furthermore, the data confirm the presence of a yet undescribed species within the genus Campylomormyrus. (C) 2016 Elsevier Inc. All rights reserved. KW - Mormyridae KW - Multispecies-coalescent KW - Campylomormyrus KW - Geometric morphometrics KW - Microsatellites KW - Species-delimitation Y1 - 2016 U6 - https://doi.org/10.1016/j.ympev.2016.04.035 SN - 1055-7903 SN - 1095-9513 VL - 101 SP - 8 EP - 18 PB - Elsevier CY - San Diego ER - TY - JOUR A1 - Paul, Christiane A1 - Kirschbaum, Frank A1 - Mamonekene, Victor A1 - Tiedemann, Ralph T1 - Evidence for Non-neutral Evolution in a Sodium Channel Gene in African Weakly Electric Fish (Campylomormyrus, Mormyridae) JF - Journal of molecular evolution N2 - Voltage-gated sodium channels, Nav1, play a crucial role in the generation and propagation of action potentials and substantially contribute to the shape of their rising phase. The electric organ discharge (EOD) of African weakly electric fish (Mormyroidea) is the sum of action potentials fired from all electrocytes of the electric organ at the same time and hence voltage-gated sodium channels are one factor—together with the electrocyte’s morphology and innervation pattern—that determines the properties of these EODs. Due to the fish-specific genome duplication, teleost fish possess eight copies of sodium channel genes (SCN), which encode for Nav1 channels. In mormyroids, SCN4aa is solely expressed in the electrocytes of the adult electric organ. In this study, we compared entire SCN4aa sequences of six species of the genus Campylomormyrus and identified nonsynonymous substitutions among them. SCN4aa in Campylomormyrus exhibits a much higher evolutionary rate compared to its paralog SCN4ab, whose expression is not restricted to the electric organ. We also found evidence for strong positive selection on the SCN4aa gene within Mormyridae and along the lineage ancestral to the Mormyridae. We have identified sites at which all nonelectric teleosts are monomorphic in their amino acid, but mormyrids have different amino acids. Our findings confirm the crucial role of SCN4aa in EOD evolution among mormyrid weakly electric fish. The inferred positive selection within Mormyridae makes this gene a prime candidate for further investigation of the divergent evolution of pulse-type EODs among closely related species. KW - Mormyridae KW - Mormyroidea KW - Campylomormyrus KW - SCN4aa KW - Voltage-gated sodium channel KW - Positive selection Y1 - 2016 U6 - https://doi.org/10.1007/s00239-016-9754-8 SN - 0022-2844 SN - 1432-1432 VL - 83 SP - 61 EP - 77 PB - Springer CY - New York ER - TY - JOUR A1 - Hartmann, Bianca A1 - Wai, Timothy A1 - Hu, Hao A1 - MacVicar, Thomas A1 - Musante, Luciana A1 - Fischer-Zirnsak, Björn A1 - Stenzel, Werner A1 - Gräf, Ralph A1 - van den Heuvel, Lambert A1 - Ropers, Hans-Hilger A1 - Wienker, Thomas F. A1 - Hübner, Christoph A1 - Langer, Thomas A1 - Kaindl, Angela M. T1 - Homozygous YME1L1 Mutation Causes Mitochondriopathy with Optic Atrophy and Mitochondrial Network Fragmentation JF - eLife N2 - Mitochondriopathies often present clinically as multisystemic disorders of primarily high-energy consuming organs. Assembly, turnover, and surveillance of mitochondrial proteins are essential for mitochondrial function and a key task of AAA family members of metalloproteases. We identified a homozygous mutation in the nuclear encoded mitochondrial escape 1-like 1 gene YME1L1, member of the AAA protease family, as a cause of a novel mitochondriopathy in a consanguineous pedigree of Saudi Arabian descent. The homozygous missense mutation, located in a highly conserved region in the mitochondrial pre-sequence, inhibits cleavage of YME1L1 by the mitochondrial processing peptidase, which culminates in the rapid degradation of YME1L1 precursor protein. Impaired YME1L1 function causes a proliferation defect and mitochondrial network fragmentation due to abnormal processing of OPA1. Our results identify mutations in YME1L1 as a cause of a mitochondriopathy with optic nerve atrophy highlighting the importance of YME1L1 for mitochondrial functionality in humans. KW - YME1L1 KW - mitochondriopathy KW - intellectual disability KW - optic atrophy KW - OPA1 KW - mitochondrial fragmentation Y1 - 2016 U6 - https://doi.org/10.7554/eLife.16078 SN - 2050-084X VL - 5 SP - 1156 EP - 1165 PB - eLife Sciences Publications CY - Cambridge ER - TY - JOUR A1 - Putzler, Sascha A1 - Meyer, Irene A1 - Gräf, Ralph T1 - CP91 is a component of the Dictyostelium centrosome involved in centrosome biogenesis JF - European journal of cell biology N2 - The Dictyostelium centrosome is a model for acentriolar centrosomes and it consists of a three-layered core structure surrounded by a corona harboring microtubule nucleation complexes. Its core structure duplicates once per cell cycle at the G2/M transition. Through proteomic analysis of isolated centrosomes we have identified CP91, a 91-kDa coiled coil protein that was localized at the centrosomal core structure. While GFP-CP91 showed almost no mobility in FRAP experiments during interphase, both GFP-CP91 and endogenous CP91 dissociated during mitosis and were absent from spindle poles from late prophase to anaphase. Since this behavior correlates with the disappearance of the central layer upon centrosome duplication, CP91 is a putative component of this layer. When expressed as GFP-fusions, CP91 fragments corresponding to the central coiled coil domain and the preceding N-terminal part (GFP-CP91cc and GFP-CP91N, respectively) also localized to the centrosome but did not show the mitotic redistribution of the full length protein suggesting a regulatory role of the C-terminal domain. Expression of all GFP-fusion proteins suppressed expression of endogenous CP91 and elicited supernumerary centrosomes. This was also very prominent upon depletion of CP91 by RNAi. Additionally, CP91-RNAi cells exhibited heavily increased ploidy due to severe defects in chromosome segregation along with increased cell size and defects in the abscission process during cytokinesis. Our results indicate that CP91 is a central centrosomal core component required for centrosomal integrity, proper centrosome biogenesis and, independently, for abscission during cytokinesis. (c) 2016 Elsevier GmbH. All rights reserved. KW - Dictyostelium KW - Mitosis KW - Microtubules KW - Centrosome KW - Nucleus Y1 - 2016 U6 - https://doi.org/10.1016/j.ejcb.2016.03.001 SN - 0171-9335 SN - 1618-1298 VL - 95 SP - 124 EP - 135 PB - Royal Society CY - Jena ER - TY - JOUR A1 - Batsios, Petros A1 - Ren, Xiang A1 - Baumann, Otto A1 - Larochelle, Denis A. A1 - Gräf, Ralph T1 - Src1 is a Protein of the Inner Nuclear Membrane Interacting with the Dictyostelium Lamin NE81 JF - Cells N2 - The nuclear envelope (NE) consists of the outer and inner nuclear membrane (INM), whereby the latter is bound to the nuclear lamina. Src1 is a Dictyostelium homologue of the helix-extension-helix family of proteins, which also includes the human lamin-binding protein MAN1. Both endogenous Src1 and GFP-Src1 are localized to the NE during the entire cell cycle. Immuno-electron microscopy and light microscopy after differential detergent treatment indicated that Src1 resides in the INM. FRAP experiments with GFP-Src1 cells suggested that at least a fraction of the protein could be stably engaged in forming the nuclear lamina together with the Dictyostelium lamin NE81. Both a BioID proximity assay and mis-localization of soluble, truncated mRFP-Src1 at cytosolic clusters consisting of an intentionally mis-localized mutant of GFP-NE81 confirmed an interaction of Src1 and NE81. Expression GFP-Src11–646, a fragment C-terminally truncated after the first transmembrane domain, disrupted interaction of nuclear membranes with the nuclear lamina, as cells formed protrusions of the NE that were dependent on cytoskeletal pulling forces. Protrusions were dependent on intact microtubules but not actin filaments. Our results indicate that Src1 is required for integrity of the NE and highlight Dictyostelium as a promising model for the evolution of nuclear architecture. KW - Dictyostelium KW - lamin KW - nuclear lamina KW - nucleus KW - nucleolus KW - HeH-protein KW - LEM-domain protein Y1 - 2016 U6 - https://doi.org/10.3390/cells5010013 SN - 2073-4409 VL - 5 IS - 1 PB - MDPI CY - Basel ER - TY - JOUR A1 - Edlich, Alexander A1 - Gerecke, Christian A1 - Giulbudagian, Michael A1 - Neumann, Falko A1 - Hedtrich, Sarah A1 - Schaefer-Korting, Monika A1 - Ma, Nan A1 - Calderon, Marcelo A1 - Kleuser, Burkhard T1 - Specific uptake mechanisms of well-tolerated thermoresponsive polyglycerol-based nanogels in antigen-presenting cells of the skin JF - European Journal of Pharmaceutics and Biopharmaceutics N2 - Engineered nanogels are of high value for a targeted and controlled transport of compounds due to the ability to change their chemical properties by external stimuli. As it has been indicated that nanogels possess a high ability to penetrate the stratum corneum, it cannot be excluded that nanogels interact with dermal dendritic cells, especially in diseased skin. In this study the potential crosstalk of the thermore-sponsive nanogels (tNGs) with the dendritic cells of the skin was investigated with the aim to determine the immunotoxicological properties of the nanogels. The investigated tNGs were made of dendritic polyglycerol (dPG) and poly(glycidyl methyl ether-co-ethyl glycidyl ether) (p(GME-co-EGE)), as polymer conferring thermoresponsive properties. Although the tNGs were taken up, they displayed neither cytotoxic and genotoxic effects nor any induction of reactive oxygen species in the tested cells. Interestingly, specific uptake mechanisms of the tNGs by the dendritic cells were depending on the nanogels cloud point temperature (Tcp), which determines the phase transition of the nanoparticle. The study points to caveolae-mediated endocytosis as being the major tNGs uptake mechanism at 37 degrees C, which is above the Tcp of the tNGs. Remarkably, an additional uptake mechanism, beside caveolae-mediated endocytosis, was observed at 29 degrees C, which is the Tcp of the tNGs. At this temperature, which is characterized by two different states of the tNGs, macropinocytosis was involved as well. In summary, our study highlights the impact of thermoresponsivity on the cellular uptake mechanisms which has to be taken into account if the tNGs are used as a drug delivery system. KW - Dendritic cells KW - Drug delivery systems KW - Nanogel KW - Nanoparticle KW - Nanoparticle uptake KW - Nanotoxicology Y1 - 2017 U6 - https://doi.org/10.1016/j.ejpb.2016.12.016 SN - 0939-6411 SN - 1873-3441 VL - 116 SP - 155 EP - 163 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Heinze, Johannes A1 - Gensch, Sabine A1 - Weber, Ewald A1 - Joshi, Jasmin Radha T1 - Soil temperature modifies effects of soil biota on plant growth JF - Journal of plant ecology N2 - Aims Plants directly and indirectly interact with many abiotic and biotic soil components. Research so far mostly focused on direct, individual abiotic or biotic effects on plant growth, but only few studies tested the indirect effects of abiotic soil factors on plant growth. Therefore, we investigated how abiotic soil conditions affect plant performance, via changes induced by soil biota. Methods In a full-factorial experiment, we grew the widespread grass Dactylis glomerata either with or without soil biota and investigated the impact of soil temperature, fertility and moisture on the soil biota effects on plant growth. We measured biomass production, root traits and colonization by arbuscular mycorrhizal fungi as well as microbial respiration. Important Findings We found significant interaction effects between abiotic soil conditions and soil biota on plant growth for fertility, but especially for soil temperature, as an increase of 10 degrees C significantly changed the soil biota effects on plant growth from positive to neutral. However, if tested individually, an increase in soil temperature and fertility per se positively affected plant biomass production, whereas soil biota per se did not affect overall plant growth, but both influenced root architecture. By affecting soil microbial activity and root architecture, soil temperature might influence both mutualistic and pathogenic interactions between plants and soil biota. Such soil temperature effects should be considered in soil feedback studies to ensure greater transferability of results from artificial and experimental conditions to natural environmental conditions. KW - plant-soil interaction KW - soil biota KW - abiotic soil factors KW - root traits KW - plant growth Y1 - 2016 U6 - https://doi.org/10.1093/jpe/rtw097 SN - 1752-9921 SN - 1752-993X VL - 10 SP - 808 EP - 821 PB - Oxford Univ. Press CY - Oxford ER - TY - JOUR A1 - Dellinger, Agnes S. A1 - Essl, Franz A1 - Hojsgaard, Diego A1 - Kirchheimer, Bernhard A1 - Klatt, Simone A1 - Dawson, Wayne A1 - Pergl, Jan A1 - Pysek, Petr A1 - van Kleunen, Mark A1 - Weber, Ewald A1 - Winter, Marten A1 - Hoerandl, Elvira A1 - Dullinger, Stefan T1 - Niche dynamics of alien species do not differ among sexual and apomictic flowering plants JF - New phytologist : international journal of plant science N2 - We compiled global occurrence data sets of 13 congeneric sexual and apomictic species pairs, and used principal components analysis (PCA) and kernel smoothers to compare changes in climatic niche optima, breadths and unfilling/expansion between native and alien ranges. Niche change metrics were compared between sexual and apomictic species. All 26 species showed changes in niche optima and/or breadth and 14 species significantly expanded their climatic niches. However, we found no effect of the reproductive system on niche dynamics. Instead, species with narrower native niches showed higher rates of niche expansion in the alien ranges. Our results suggest that niche shifts are frequent in plant invasions but evolutionary potential may not be of major importance for such shifts. Niche dynamics rather appear to be driven by changes of the realized niche without adaptive change of the fundamental climatic niche. KW - adaptation KW - asexual reproduction KW - niche shifts KW - plant invasion KW - reproductive system KW - species distribution modelling Y1 - 2016 U6 - https://doi.org/10.1111/nph.13694 SN - 0028-646X SN - 1469-8137 VL - 209 SP - 1313 EP - 1323 PB - Wiley-Blackwell CY - Hoboken ER - TY - JOUR A1 - Westbury, Michael V. A1 - Prost, Stefan A1 - Seelenfreund, Andrea A1 - Ramirez, Jose-Miguel A1 - Matisoo-Smith, Elizabeth A. A1 - Knapp, Michael T1 - First complete mitochondrial genome data from ancient South American camelids - The mystery of the chilihueques from Isla Mocha (Chile) JF - Scientific reports Y1 - 2016 U6 - https://doi.org/10.1038/srep38708 SN - 2045-2322 VL - 6 PB - Nature Publ. Group CY - London ER - TY - JOUR A1 - Lämke, Jörn A1 - Brzezinka, Krzysztof A1 - Altmann, Simone A1 - Bäurle, Isabel T1 - A hit-and-run heat shock factor governs sustained histone methylation and transcriptional stress memory JF - The EMBO journal N2 - In nature, plants often encounter chronic or recurring stressful conditions. Recent results indicate that plants can remember a past exposure to stress to be better prepared for a future stress incident. However, the molecular basis of this is poorly understood. Here, we report the involvement of chromatin modifications in the maintenance of acquired thermotolerance (heat stress [HS] memory). HS memory is associated with the accumulation of histone H3 lysine 4 di- and trimethylation at memory-related loci. This accumulation outlasts their transcriptional activity and marks them as recently transcriptionally active. High accumulation of H3K4 methylation is associated with hyper-induction of gene expression upon a recurring HS. This transcriptional memory and the sustained accumulation of H3K4 methylation depend on HSFA2, a transcription factor that is required for HS memory, but not initial heat responses. Interestingly, HSFA2 associates with memory-related loci transiently during the early stages following HS. In summary, we show that transcriptional memory after HS is associated with sustained H3K4 hyper-methylation and depends on a hit-and-run transcription factor, thus providing a molecular framework for HS memory. KW - chromatin KW - H3K4 methylation KW - heat shock transcription factor KW - priming KW - transcriptional memory Y1 - 2016 U6 - https://doi.org/10.15252/embj.201592593 SN - 0261-4189 SN - 1460-2075 VL - 35 SP - 162 EP - 175 PB - Wiley-Blackwell CY - Hoboken ER - TY - JOUR A1 - Nowak-Szczepanska, Natalia A1 - Gomula, A. A1 - Ipsen, Marie Josephin A1 - Koziel, Slawomir T1 - Different effects of living conditions on the variation in BMI and height in children before the onset of puberty JF - European journal of clinical nutrition N2 - SUBJECTS/METHODS: The study included 5597 boys and 5479 girls aged 7-8 years of age. Socioeconomic status (SES) was defined in three categories: high, medium and low. RESULTS: Between 1966 and 2012, the mean values for height and BMI significantly increased in both sexes (P<0.001). The variation of these two parameters, however, showed a different pattern. Whereas the variation in Z-values for height remained unchanged in both sexes, the variation in BMI increased in boys (P<0.01) but not in girls. SES affected the variation in Z-BMI in 1978 in both sexes (P<0.001), whereas variation in Z-height between SES categories remained unchanged across all years of surveys in boys. Before the political transformation, significant regional differences were observed in the variances of Z-BMI (P<0.05) but not of Z-height. This pattern changed after the political transformation, when regional differences in variances of Z-BMI disappeared. CONCLUSIONS: It is concluded that the mean values and the variation of BMI are affected by a changing quality of life, whereas the variation in height is usually independent of living conditions. Y1 - 2016 U6 - https://doi.org/10.1038/ejcn.2016.30 SN - 0954-3007 SN - 1476-5640 VL - 70 SP - 662 EP - 666 PB - Nature Publ. Group CY - London ER - TY - JOUR A1 - Wacker, Alexander A1 - Piepho, Maike A1 - Harwood, John L. A1 - Guschina, Irina A. A1 - Arts, Michael T. T1 - Light-Induced Changes in Fatty Acid Profiles of Specific Lipid Classes in Several Freshwater Phytoplankton Species JF - Frontiers in plant science : FPLS N2 - We tested the influence of two light intensities [40 and 300 μmol PAR / (m2s)] on the fatty acid composition of three distinct lipid classes in four freshwater phytoplankton species. We chose species of different taxonomic classes in order to detect potentially similar reaction characteristics that might also be present in natural phytoplankton communities. From samples of the bacillariophyte Asterionella formosa, the chrysophyte Chromulina sp., the cryptophyte Cryptomonas ovata and the zygnematophyte Cosmarium botrytis we first separated glycolipids (monogalactosyldiacylglycerol, digalactosyldiacylglycerol, and sulfoquinovosyldiacylglycerol), phospholipids (phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylinositol, and phosphatidylserine) as well as non-polar lipids (triacylglycerols), before analyzing the fatty acid composition of each lipid class. High variation in the fatty acid composition existed among different species. Individual fatty acid compositions differed in their reaction to changing light intensities in the four species. Although no generalizations could be made for species across taxonomic classes, individual species showed clear but small responses in their ecologically-relevant omega-3 and omega-6 polyunsaturated fatty acids (PUFA) in terms of proportions and of per tissue carbon quotas. Knowledge on how lipids like fatty acids change with environmental or culture conditions is of great interest in ecological food web studies, aquaculture, and biotechnology, since algal lipids are the most important sources of omega-3 long-chain PUFA for aquatic and terrestrial consumers, including humans. KW - freshwater algae KW - light adaptation KW - lipid classes KW - fatty acid changes Y1 - 2016 U6 - https://doi.org/10.3389/fpls.2016.00264 SN - 1664-462X VL - 7 SP - 1 EP - 13 PB - Frontiers Media CY - Lausanne ER - TY - JOUR A1 - Koussoroplis, Apostolos-Manuel A1 - Wacker, Alexander T1 - Covariance modulates the effect of joint temperature and food variance on ectotherm life-history traits JF - Ecology letters N2 - Understanding animal performance in heterogeneous or variable environments is a central question in ecology. We combine modelling and experiments to test how temperature and food availability variance jointly affect life-history traits of ectotherms. The model predicts that as mean temperatures move away from the ectotherm's thermal optimum, the effect size of joint thermal and food variance should become increasingly sensitive to their covariance. Below the thermal optimum, performance should be positively correlated with food–temperature covariance and the opposite is predicted above it. At lower temperatures, covariance should determine whether food and temperature variance increases or decreases performance compared to constant conditions. Somewhat stronger than predicted, the covariance effect below the thermal optimum was confirmed experimentally on an aquatic ectotherm (Daphnia magna) exposed to diurnal food and temperature variance with different amounts of covariance. Our findings have important implications for understanding ectotherm responses to climate-driven alterations of thermal mean and variance. KW - Biotic interactions KW - co-limitation KW - Daphnia KW - environmental fluctuations KW - heterogeneity KW - variability KW - vertical migration KW - zooplankton Y1 - 2016 U6 - https://doi.org/10.1111/ele.12546 SN - 1461-023X SN - 1461-0248 VL - 19 SP - 143 EP - 152 PB - Wiley-Blackwell CY - Hoboken ER - TY - JOUR A1 - Kabelitz, Tina A1 - Brzezinka, Krzysztof A1 - Friedrich, Thomas A1 - Gorka, Michal A1 - Graf, Alexander A1 - Kappel, Christian A1 - Bäurle, Isabel T1 - A JUMONJI Protein with E3 Ligase and Histone H3 Binding Activities Affects Transposon Silencing in Arabidopsis JF - Plant physiology : an international journal devoted to physiology, biochemistry, cellular and molecular biology, biophysics and environmental biology of plants N2 - Transposable elements (TEs) make up a large proportion of eukaryotic genomes. As their mobilization creates genetic variation that threatens genome integrity, TEs are epigenetically silenced through several pathways, and this may spread to neighboring sequences. JUMONJI (JMJ) proteins can function as antisilencing factors and prevent silencing of genes next to TEs. Whether TE silencing is counterbalanced by the activity of antisilencing factors is still unclear. Here, we characterize JMJ24 as a regulator of TE silencing. We show that loss of JMJ24 results in increased silencing of the DNA transposon AtMu1c, while overexpression of JMJ24 reduces silencing. JMJ24 has a JumonjiC (JmjC) domain and two RING domains. JMJ24 autoubiquitinates in vitro, demonstrating E3 ligase activity of the RING domain(s). JMJ24-JmjC binds the N-terminal tail of histone H3, and full-length JMJ24 binds histone H3 in vivo. JMJ24 activity is anticorrelated with histone H3 Lys 9 dimethylation (H3K9me2) levels at AtMu1c. Double mutant analyses with epigenetic silencing mutants suggest that JMJ24 antagonizes histone H3K9me2 and requires H3K9 methyltransferases for its activity on AtMu1c. Genome-wide transcriptome analysis indicates that JMJ24 affects silencing at additional TEs. Our results suggest that the JmjC domain of JMJ24 has lost demethylase activity but has been retained as a binding domain for histone H3. This is in line with phylogenetic analyses indicating that JMJ24 (with the mutated JmjC domain) is widely conserved in angiosperms. Taken together, this study assigns a role in TE silencing to a conserved JmjC-domain protein with E3 ligase activity, but no demethylase activity. Y1 - 2016 U6 - https://doi.org/10.1104/pp.15.01688 SN - 0032-0889 SN - 1532-2548 VL - 171 SP - 344 EP - 358 PB - American Society of Plant Physiologists CY - Rockville ER - TY - JOUR A1 - Grzesiuk, Malgorzata A1 - Wacker, Alexander A1 - Spijkerman, Elly T1 - Photosynthetic sensitivity of phytoplankton to commonly used pharmaceuticals and its dependence on cellular phosphorus status JF - Ecotoxicology N2 - Recently pharmaceuticals have become significant environmental pollutants in aquatic ecosystems, that could affect primary producers such as microalgae. Here we analyzed the effect of pharmaceuticals on the photosynthesis of microalgae commonly found in freshwater-two species of Chlorophyceae and a member of the Eustigmatophyceae, via PAM fluorometry. As pharmaceuticals, three medicines often consumed in households were chosen: (i) fluoxetine, an antidepressant, (ii) propranolol, a beta-blocker and (iii) ibuprofen, an anti-inflammatory and analgesic medicine. The EC50 for the quantum yield of photosystem II in phytoplankton acclimated to inorganic phosphorus (P-i)-replete and P-i-limited conditions was estimated. Acute toxicity experiments over a 5 h exposure revealed that Nannochloropsis limnetica was the least sensitive to pharmaceuticals in its photosynthetic yield out of all species tested. Although the estimation of sub-lethal effects can be vital in contrast to that of LC(50)s, the EC50 values in all species and for all medicines were orders of magnitude higher than concentrations found in polluted surface water. Chlamydomonas reinhardtii was the most sensitive to fluoxetine (EC50 of 1.6 mg L-1), and propranolol (EC50 of 3 mg L-1). Acutodesmus obliquus was most sensitive to ibuprofen (EC50 of 288 mg L-1). Additionally, the sensitivity to the pharmaceuticals changed under a P-i-limitation; the green algae became less sensitive to fluoxetine and propranolol. In contrast, P-i-limited algal species were more sensitive to ibuprofen. Our results suggest that the sensitivity of algae to pharmaceuticals is (i) highly compound- and species-specific and (ii) dependent on the cellular P status. KW - Freshwater algae KW - Medicine KW - EC50 KW - PAM fluorometry KW - Tolerance Y1 - 2016 U6 - https://doi.org/10.1007/s10646-016-1628-8 SN - 0963-9292 SN - 1573-3017 VL - 25 SP - 697 EP - 707 PB - Springer CY - Dordrecht ER - TY - JOUR A1 - Lachmann, Sabrina C. A1 - Maberly, Stephen C. A1 - Spijkerman, Elly T1 - ECOPHYSIOLOGY MATTERS: LINKING INORGANIC CARBON ACQUISITION TO ECOLOGICAL PREFERENCE IN FOUR SPECIES OF MICROALGAE (CHLOROPHYCEAE) JF - Journal of phycology N2 - The effect of CO2 supply is likely to play an important role in algal ecology. Since inorganic carbon (C-i) acquisition strategies are very diverse among microalgae and C-i availability varies greatly within and among habitats, we hypothesized that C-i acquisition depends on the pH of their preferred natural environment (adaptation) and that the efficiency of C-i uptake is affected by CO2 availability (acclimation). To test this, four species of green algae originating from different habitats were studied. The pH-drift and C-i uptake kinetic experiments were used to characterize C-i acquisition strategies and their ability to acclimate to high and low CO2 conditions and high and low pH was evaluated. Results from pH drift experiments revealed that the acidophile and acidotolerant Chlamydomonas species were mainly restricted to CO2, whereas the two neutrophiles were efficient bicarbonate users. CO2 compensation points in low CO2-acclimated cultures ranged between 0.6 and 1.4 mu M CO2 and acclimation to different culture pH and CO2 conditions suggested that CO2 concentrating mechanisms were present in most species. High CO2 acclimated cultures adapted rapidly to low CO2 condition during pH-drifts. C-i uptake kinetics at different pH values showed that the affinity for C-i was largely influenced by external pH, being highest under conditions where CO2 dominated the C-i pool. In conclusion, C-i acquisition was highly variable among four species of green algae and linked to growth pH preference, suggesting that there is a connection between C-i acquisition and ecological distribution. KW - acidophile KW - carbon acquisition KW - CCM KW - Chlamydomonas KW - Chlorella KW - CO2 supply KW - extremophile KW - inorganic carbon uptake kinetics KW - pH-drift KW - Scenedesmus Y1 - 2016 U6 - https://doi.org/10.1111/jpy.12462 SN - 0022-3646 SN - 1529-8817 VL - 52 SP - 1051 EP - 1063 PB - Wiley-Blackwell CY - Hoboken ER - TY - JOUR A1 - Spijkerman, Elly A1 - Stojkovic, Slobodanka A1 - Holland, Daryl A1 - Lachmann, Sabrina C. A1 - Beardall, John T1 - Nutrient induced fluorescence transients (NIFTs) provide a rapid measure of P and C (co-)limitation in a green alga JF - European journal of phycology N2 - Nutrient Induced Fluorescence Transients (NIFTs) have been shown to be a possible way of testing for the limiting nutrient in algal populations. In this study we tested the hypothesis that NIFTs can be used to detect a (co-)limitation for inorganic phosphorus (Pi) and CO2 in the green alga Chlamydomonas acidophila and that the magnitude of the NIFTs can be related to cellular P:C ratios. We show a co-limitation response for Pi and CO2 via traditional nutrient enrichment experiments in natural phytoplankton populations dominated by C. acidophila. We measured NIFT responses after a Pi- or a CO2-spike in C. acidophila batch cultures at various stages of Pi and inorganic C limitation. Significant NIFTs were observed in response to spikes in both nutrients. The NIFT response to a Pi-spike showed a strong negative correlation with cellular P:C ratio that was pronounced below 3 mmol P: mol C (equivalent to 0.2 pg P cell(-1)). Both cellular P and C content influenced the extent of the Pi-NIFT response. The NIFT response to a CO2-spike correlated to low CO2 culturing conditions and also had a negative correlation with cellular P content. A secondary response within the Pi-NIFT response was related to the CO2 concentration and potentially reflected co-limitation. In conclusion, NIFTs provided a quick and reliable method to detect the growth-limiting nutrient in an extremophile green alga, under Pi-, CO2- and Pi/CO2 (co-)limited growth conditions. KW - acidophile KW - Chlamydomonas KW - CO2 concentrating mechanism KW - CO2 limitation KW - extremophile KW - nutrient limitation KW - photosynthesis response KW - phytoplankton KW - stoichiometry Y1 - 2016 U6 - https://doi.org/10.1080/09670262.2015.1095355 SN - 0967-0262 SN - 1469-4433 VL - 51 SP - 47 EP - 58 PB - Hindawi CY - Abingdon ER - TY - JOUR A1 - Cui, Huanhuan A1 - Schlesinger, Jenny A1 - Schoenhals, Sophia A1 - Toenjes, Martje A1 - Dunkel, Ilona A1 - Meierhofer, David A1 - Cano, Elena A1 - Schulz, Kerstin A1 - Berger, Michael F. A1 - Haack, Timm A1 - Abdelilah-Seyfried, Salim A1 - Bulyk, Martha L. A1 - Sauer, Sascha A1 - Sperling, Silke R. T1 - Phosphorylation of the chromatin remodeling factor DPF3a induces cardiac hypertrophy through releasing HEY repressors from DNA JF - Nucleic acids research N2 - DPF3 (BAF45c) is a member of the BAF chromatin remodeling complex. Two isoforms have been described, namely DPF3a and DPF3b. The latter binds to acetylated and methylated lysine residues of histones. Here, we elaborate on the role of DPF3a and describe a novel pathway of cardiac gene transcription leading to pathological cardiac hypertrophy. Upon hypertrophic stimuli, casein kinase 2 phosphorylates DPF3a at serine 348. This initiates the interaction of DPF3a with the transcriptional repressors HEY, followed by the release of HEY from the DNA. Moreover, BRG1 is bound by DPF3a, and is thus recruited to HEY genomic targets upon interaction of the two components. Consequently, the transcription of downstream targets such as NPPA and GATA4 is initiated and pathological cardiac hypertrophy is established. In human, DPF3a is significantly up-regulated in hypertrophic hearts of patients with hypertrophic cardiomyopathy or aortic stenosis. Taken together, we show that activation of DPF3a upon hypertrophic stimuli switches cardiac fetal gene expression from being silenced by HEY to being activated by BRG1. Thus, we present a novel pathway for pathological cardiac hypertrophy, whose inhibition is a long-term therapeutic goal for the treatment of the course of heart failure. Y1 - 2016 U6 - https://doi.org/10.1093/nar/gkv1244 SN - 0305-1048 SN - 1362-4962 VL - 44 SP - 2538 EP - 2553 PB - Oxford Univ. Press CY - Oxford ER - TY - JOUR A1 - ´Cwiek-Kupczynska, Hanna A1 - Altmann, Thomas A1 - Arend, Daniel A1 - Arnaud, Elizabeth A1 - Chen, Dijun A1 - Cornut, Guillaume A1 - Fiorani, Fabio A1 - Frohmberg, Wojciech A1 - Junker, Astrid A1 - Klukas, Christian A1 - Lange, Matthias A1 - Mazurek, Cezary A1 - Nafissi, Anahita A1 - Neveu, Pascal A1 - van Oeveren, Jan A1 - Pommier, Cyril A1 - Poorter, Hendrik A1 - Rocca-Serra, Philippe A1 - Sansone, Susanna-Assunta A1 - Scholz, Uwe A1 - van Schriek, Marco A1 - Seren, Ümit A1 - Usadel, Bjorn A1 - Weise, Stephan A1 - Kersey, Paul A1 - Krajewski, Pawel T1 - Measures for interoperability of phenotypic data: minimum information requirements and formatting JF - Plant Methods N2 - Background: Plant phenotypic data shrouds a wealth of information which, when accurately analysed and linked to other data types, brings to light the knowledge about the mechanisms of life. As phenotyping is a field of research comprising manifold, diverse and time-consuming experiments, the findings can be fostered by reusing and combining existing datasets. Their correct interpretation, and thus replicability, comparability and interoperability, is possible provided that the collected observations are equipped with an adequate set of metadata. So far there have been no common standards governing phenotypic data description, which hampered data exchange and reuse. Results: In this paper we propose the guidelines for proper handling of the information about plant phenotyping experiments, in terms of both the recommended content of the description and its formatting. We provide a document called "Minimum Information About a Plant Phenotyping Experiment", which specifies what information about each experiment should be given, and a Phenotyping Configuration for the ISA-Tab format, which allows to practically organise this information within a dataset. We provide examples of ISA-Tab-formatted phenotypic data, and a general description of a few systems where the recommendations have been implemented. Conclusions: Acceptance of the rules described in this paper by the plant phenotyping community will help to achieve findable, accessible, interoperable and reusable data. KW - Data standardisation and formatting KW - Experimental metadata KW - Minimum information recommendations KW - Plant phenotyping KW - Experiment description Y1 - 2016 U6 - https://doi.org/10.1186/s13007-016-0144-4 SN - 1746-4811 VL - 12 PB - BioMed Central CY - London ER - TY - JOUR A1 - Yan, Wenhao A1 - Chen, Dijun A1 - Kaufmann, Kerstin T1 - Efficient multiplex mutagenesis by RNA-guided Cas9 and its use in the characterization of regulatory elements in the AGAMOUS gene JF - Plant methods N2 - Background The efficiency of multiplex editing in plants by the RNA-guided Cas9 system is limited by efficient introduction of its components into the genome and by their activity. The possibility of introducing large fragment deletions by RNA-guided Cas9 tool provides the potential to study the function of any DNA region of interest in its ‘endogenous’ environment. Results Here, an RNA-guided Cas9 system was optimized to enable efficient multiplex editing in Arabidopsis thaliana. We demonstrate the flexibility of our system for knockout of multiple genes, and to generate heritable large-fragment deletions in the genome. As a proof of concept, the function of part of the second intron of the flower development gene AGAMOUS in Arabidopsis was studied by generating a Cas9-free mutant plant line in which part of this intron was removed from the genome. Further analysis revealed that deletion of this intron fragment results 40 % decrease of AGAMOUS gene expression without changing the splicing of the gene which indicates that this regulatory region functions as an activator of AGAMOUS gene expression. Conclusions Our modified RNA-guided Cas9 system offers a versatile tool for the functional dissection of coding and non-coding DNA sequences in plants. KW - RNA-guided Cas9 KW - Multiplex mutagenesis KW - Large fragment deletion KW - Germline transmission Y1 - 2016 U6 - https://doi.org/10.1186/s13007-016-0125-7 SN - 1746-4811 VL - 12 SP - 1 EP - 9 PB - BioMed Central CY - London ER - TY - JOUR A1 - Yan, Wenhao A1 - Chen, Dijun A1 - Kaufmann, Kerstin T1 - Efficient multiplex mutagenesis by RNA-guided Cas9 and its use in the characterization of regulatory elements in the AGAMOUS gene JF - Plant Methods N2 - Results: Here, an RNA-guided Cas9 system was optimized to enable efficient multiplex editing in Arabidopsis thaliana. We demonstrate the flexibility of our system for knockout of multiple genes, and to generate heritable large-fragment deletions in the genome. As a proof of concept, the function of part of the second intron of the flower development gene AGAMOUS in Arabidopsis was studied by generating a Cas9-free mutant plant line in which part of this intron was removed from the genome. Further analysis revealed that deletion of this intron fragment results 40 % decrease of AGAMOUS gene expression without changing the splicing of the gene which indicates that this regulatory region functions as an activator of AGAMOUS gene expression. Conclusions: Our modified RNA-guided Cas9 system offers a versatile tool for the functional dissection of coding and non-coding DNA sequences in plants. KW - RNA-guided Cas9 KW - Multiplex mutagenesis KW - Large fragment deletion KW - Germline transmission Y1 - 2016 U6 - https://doi.org/10.1186/s13007-016-0125-7 SN - 1746-4811 VL - 12 SP - 2381 EP - 2389 PB - BioMed Central CY - London ER - TY - JOUR A1 - Memczak, Henry A1 - Lauster, Daniel A1 - Kar, Parimal A1 - Di Lella, Santiago A1 - Volkmer, Rudolf A1 - Knecht, Volker A1 - Herrmann, Andreas A1 - Ehrentreich-Foerster, Eva A1 - Bier, Frank Fabian A1 - Stoecklein, Walter F. M. T1 - Anti-Hemagglutinin Antibody Derived Lead Peptides for Inhibitors of Influenza Virus Binding JF - PLoS one N2 - Antibodies against spike proteins of influenza are used as a tool for characterization of viruses and therapeutic approaches. However, development, production and quality control of antibodies is expensive and time consuming. To circumvent these difficulties, three peptides were derived from complementarity determining regions of an antibody heavy chain against influenza A spike glycoprotein. Their binding properties were studied experimentally, and by molecular dynamics simulations. Two peptide candidates showed binding to influenza A/Aichi/2/68 H3N2. One of them, termed PeB, with the highest affinity prevented binding to and infection of target cells in the micromolar region without any cytotoxic effect. PeB matches best the conserved receptor binding site of hemagglutinin. PeB bound also to other medical relevant influenza strains, such as human-pathogenic A/California/7/2009 H1N1, and avian-pathogenic A/MuteSwan/Rostock/R901/2006 H7N1. Strategies to improve the affinity and to adapt specificity are discussed and exemplified by a double amino acid substituted peptide, obtained by substitutional analysis. The peptides and their derivatives are of great potential for drug development as well as biosensing. Y1 - 2016 U6 - https://doi.org/10.1371/journal.pone.0159074 SN - 1932-6203 VL - 11 SP - 82 EP - 90 PB - PLoS CY - San Fransisco ER - TY - JOUR A1 - Connor, Daniel Oliver A1 - Zantow, Jonas A1 - Hust, Michael A1 - Bier, Frank Fabian A1 - von Nickisch-Rosenegk, Markus T1 - Identification of Novel Immunogenic Proteins of Neisseria gonorrhoeae by Phage Display JF - PLoS one N2 - Neisseria gonorrhoeae is one of the most prevalent sexually transmitted diseases worldwide with more than 100 million new infections per year. A lack of intense research over the last decades and increasing resistances to the recommended antibiotics call for a better understanding of gonococcal infection, fast diagnostics and therapeutic measures against N. gonorrhoeae. Therefore, the aim of this work was to identify novel immunogenic proteins as a first step to advance those unresolved problems. For the identification of immunogenic proteins, pHORF oligopeptide phage display libraries of the entire N. gonorrhoeae genome were constructed. Several immunogenic oligopeptides were identified using polyclonal rabbit antibodies against N. gonorrhoeae. Corresponding full-length proteins of the identified oligopeptides were expressed and their immunogenic character was verified by ELISA. The immunogenic character of six proteins was identified for the first time. Additional 13 proteins were verified as immunogenic proteins in N. gonorrhoeae. Y1 - 2016 U6 - https://doi.org/10.1371/journal.pone.0148986 SN - 1932-6203 VL - 11 PB - PLoS CY - San Fransisco ER - TY - JOUR A1 - Bader, Denise A1 - Klier, Dennis Tobias A1 - Hettrich, C. A1 - Bier, Frank Fabian A1 - Wessig, Pablo T1 - Detecting carbohydrate-lectin interactions using a fluorescent probe based on DBD dyes JF - Analytical methods : advancing methods and applications N2 - Herein we present an efficient synthesis of a biomimetic probe with modular construction that can be specifically bound by the mannose binding FimH protein - a surface adhesion protein of E. coli bacteria. The synthesis combines the new and interesting DBD dye with the carbohydrate ligand mannose via a Click reaction. We demonstrate the binding to E. coli bacteria over a large concentration range and also present some special characteristics of those molecules that are of particular interest for the application as a biosensor. In particular, the mix-and-measure ability and the very good photo-stability should be highlighted here. Y1 - 2016 U6 - https://doi.org/10.1039/c5ay02991k SN - 1759-9660 SN - 1759-9679 VL - 8 SP - 1235 EP - 1238 PB - Royal Society of Chemistry CY - Cambridge ER - TY - JOUR A1 - Zancolli, Giulia A1 - Baker, Timothy G. A1 - Barlow, Axel A1 - Bradley, Rebecca K. A1 - Calvete, Juan J. A1 - Carter, Kimberley C. A1 - de Jager, Kaylah A1 - Owens, John Benjamin A1 - Price, Jenny Forrester A1 - Sanz, Libia A1 - Scholes-Higham, Amy A1 - Shier, Liam A1 - Wood, Liam A1 - Wüster, Catharine E. A1 - Wüster, Wolfgang T1 - Is Hybridization a Source of Adaptive Venom Variation in Rattlesnakes? A Test, Using a Crotalus scutulatus x viridis Hybrid Zone in Southwestern New Mexico JF - Toxins N2 - Venomous snakes often display extensive variation in venom composition both between and within species. However, the mechanisms underlying the distribution of different toxins and venom types among populations and taxa remain insufficiently known. Rattlesnakes (Crotalus, Sistrurus) display extreme inter-and intraspecific variation in venom composition, centered particularly on the presence or absence of presynaptically neurotoxic phospholipases A2 such as Mojave toxin (MTX). Interspecific hybridization has been invoked as a mechanism to explain the distribution of these toxins across rattlesnakes, with the implicit assumption that they are adaptively advantageous. Here, we test the potential of adaptive hybridization as a mechanism for venom evolution by assessing the distribution of genes encoding the acidic and basic subunits of Mojave toxin across a hybrid zone between MTX-positive Crotalus scutulatus and MTX-negative C. viridis in southwestern New Mexico, USA. Analyses of morphology, mitochondrial and single copy-nuclear genes document extensive admixture within a narrow hybrid zone. The genes encoding the two MTX subunits are strictly linked, and found in most hybrids and backcrossed individuals, but not in C. viridis away from the hybrid zone. Presence of the genes is invariably associated with presence of the corresponding toxin in the venom. We conclude that introgression of highly lethal neurotoxins through hybridization is not necessarily favored by natural selection in rattlesnakes, and that even extensive hybridization may not lead to introgression of these genes into another species. KW - adaptation KW - Crotalus KW - evolution KW - hybridization KW - introgression KW - Mojave toxin KW - molecular evolution KW - venom Y1 - 2016 U6 - https://doi.org/10.3390/toxins8060188 SN - 2072-6651 VL - 8 PB - MDPI CY - Basel ER - TY - JOUR A1 - González-Fortes, Gloria M. A1 - Kolbe, Ben A1 - Fernandes, Daniel A1 - Meleg, Ioana N. A1 - Garcia-Vazquez, Ana A1 - Pinto-Llona, Ana C. A1 - Constantin, Silviu A1 - de Torres, Trino J. A1 - Ortiz, Jose E. A1 - Frischauf, Christine A1 - Rabeder, Gernot A1 - Hofreiter, Michael A1 - Barlow, Axel T1 - Ancient DNA reveals differences in behaviour and sociality between brown bears and extinct cave bears JF - Molecular ecology N2 - Ancient DNA studies have revolutionized the study of extinct species and populations, providing insights on phylogeny, phylogeography, admixture and demographic history. However, inferences on behaviour and sociality have been far less frequent. Here, we investigate the complete mitochondrial genomes of extinct Late Pleistocene cave bears and middle Holocene brown bears that each inhabited multiple geographically proximate caves in northern Spain. In cave bears, we find that, although most caves were occupied simultaneously, each cave almost exclusively contains a unique lineage of closely related haplotypes. This remarkable pattern suggests extreme fidelity to their birth site in cave bears, best described as homing behaviour, and that cave bears formed stable maternal social groups at least for hibernation. In contrast, brown bears do not show any strong association of mitochondrial lineage and cave, suggesting that these two closely related species differed in aspects of their behaviour and sociality. This difference is likely to have contributed to cave bear extinction, which occurred at a time in which competition for caves between bears and humans was likely intense and the ability to rapidly colonize new hibernation sites would have been crucial for the survival of a species so dependent on caves for hibernation as cave bears. Our study demonstrates the potential of ancient DNA to uncover patterns of behaviour and sociality in ancient species and populations, even those that went extinct many tens of thousands of years ago. KW - ancient DNA KW - extinction KW - homing KW - sociality KW - Ursus arctos KW - Ursus spelaeus Y1 - 2016 U6 - https://doi.org/10.1111/mec.13800 SN - 0962-1083 SN - 1365-294X VL - 25 SP - 4907 EP - 4918 PB - Wiley-Blackwell CY - Hoboken ER - TY - JOUR A1 - Foti, Alessandro A1 - Hartmann, Tobias A1 - Coelho, Catarina A1 - Santos-Silva, Teresa A1 - Romao, Maria Joao A1 - Leimkühler, Silke T1 - Optimization of the Expression of Human Aldehyde Oxidase for Investigations of Single-Nucleotide Polymorphisms JF - Drug metabolism and disposition : the biological fate of chemicals N2 - Aldehyde oxidase (AOX1) is an enzyme with broad substrate specificity, catalyzing the oxidation of a wide range of endogenous and exogenous aldehydes as well as N-heterocyclic aromatic compounds. In humans, the enzyme’s role in phase I drug metabolism has been established and its importance is now emerging. However, the true physiologic function of AOX1 in mammals is still unknown. Further, numerous single-nucleotide polymorphisms (SNPs) have been identified in human AOX1. SNPs are a major source of interindividual variability in the human population, and SNP-based amino acid exchanges in AOX1 reportedly modulate the catalytic function of the enzyme in either a positive or negative fashion. For the reliable analysis of the effect of amino acid exchanges in human proteins, the existence of reproducible expression systems for the production of active protein in ample amounts for kinetic, spectroscopic, and crystallographic studies is required. In our study we report an optimized expression system for hAOX1 in Escherichia coli using a codon-optimized construct. The codon-optimization resulted in an up to 15-fold increase of protein production and a simplified purification procedure. The optimized expression system was used to study three SNPs that result in amino acid changes C44W, G1269R, and S1271L. In addition, the crystal structure of the S1271L SNP was solved. We demonstrate that the recombinant enzyme can be used for future studies to exploit the role of AOX in drug metabolism, and for the identification and synthesis of new drugs targeting AOX when combined with crystallographic and modeling studies. Y1 - 2016 U6 - https://doi.org/10.1124/dmd.115.068395 SN - 0090-9556 SN - 1521-009X VL - 44 SP - 1277 EP - 1285 PB - American Society for Pharmacology and Experimental Therapeutics CY - Bethesda ER - TY - JOUR A1 - Correia, Marcia A. S. A1 - Otrelo-Cardoso, Ana Rita A1 - Schwuchow, Viola A1 - Clauss, Kajsa G. V. Sigfridsson A1 - Haumann, Michael A1 - Romao, Maria Joao A1 - Leimkühler, Silke A1 - Santos-Silva, Teresa T1 - The Escherichia coli Periplasmic Aldehyde Oxidoreductase Is an Exceptional Member of the Xanthine Oxidase Family of Molybdoenzymes JF - ACS chemical biology N2 - The xanthine oxidase (XO) family comprises molybdenum-dependent enzymes that usually form homodimers (or dimers of heterodimers/trimers) organized in three domains that harbor two [2Fe-2S] clusters, one FAD, and a Mo cofactor. In this work, we crystallized an unusual member of the family, the periplasmic aldehyde oxidoreductase PaoABC from Escherichia coli. This is the first example of an E. coli protein containing a molybdopterin-cytosine-dinucleotide cofactor and is the only heterotrimer of the XO family so far structurally characterized. The crystal structure revealed the presence of an unexpected [4Fe-4S] cluster, anchored to an additional 40 residues subdomain. According to phylogenetic analysis, proteins containing this cluster are widely spread in many bacteria phyla, putatively through repeated gene transfer events. The active site of PaoABC is highly exposed to the surface with no aromatic residues and an arginine (PaoC-R440) making a direct interaction with PaoC-E692, which acts as a base catalyst. In order to understand the importance of R440, kinetic assays were carried out, and the crystal structure of the PaoC-R440H variant was also determined. Y1 - 2016 U6 - https://doi.org/10.1021/acschembio.6b00572 SN - 1554-8929 SN - 1554-8937 VL - 11 SP - 2923 EP - 2935 PB - American Chemical Society CY - Washington ER - TY - JOUR A1 - Rotics, Shay A1 - Kaatz, Michael A1 - Resheff, Yehezkel S. A1 - Turjeman, Sondra Feldman A1 - Zurell, Damaris A1 - Sapir, Nir A1 - Eggers, Ute A1 - Flack, Andrea A1 - Fiedler, Wolfgang A1 - Jeltsch, Florian A1 - Wikelski, Martin A1 - Nathan, Ran T1 - The challenges of the first migration: movement and behaviour of juvenile vs. adult white storks with insights regarding juvenile mortality JF - Journal of animal ecology : a journal of the British Ecological Society N2 - 1. Migration conveys an immense challenge, especially for juvenile birds coping with enduring and risky journeys shortly after fledging. Accordingly, juveniles exhibit considerably lower survival rates compared to adults, particularly during migration. Juvenile white storks (Ciconia ciconia), which are known to rely on adults during their first fall migration presumably for navigational purposes, also display much lower annual survival than adults. 2. Using detailed GPS and body acceleration data, we examined the patterns and potential causes of age-related differences in fall migration properties of white storks by comparing first-year juveniles and adults. We compared juvenile and adult parameters of movement, behaviour and energy expenditure (estimated from overall dynamic body acceleration) and placed this in the context of the juveniles’ lower survival rate. 3. Juveniles used flapping flight vs. soaring flight 23% more than adults and were estimated to expend 14% more energy during flight. Juveniles did not compensate for their higher flight costs by increased refuelling or resting during migration. When juveniles and adults migrated together in the same flock, the juvenile flew mostly behind the adult and was left behind when they separated. Juveniles showed greater improvement in flight efficiency throughout migration compared to adults which appears crucial because juveniles exhibiting higher flight costs suffered increased mortality. 4. Our findings demonstrate the conflict between the juveniles’ inferior flight skills and their urge to keep up with mixed adult–juvenile flocks. We suggest that increased flight costs are an important proximate cause of juvenile mortality in white storks and likely in other soaring migrants and that natural selection is operating on juvenile variation in flight efficiency. KW - flight KW - flight efficiency KW - juvenile mortality KW - migration KW - white stork Y1 - 2016 U6 - https://doi.org/10.1111/1365-2656.12525 SN - 0021-8790 SN - 1365-2656 VL - 85 SP - 938 EP - 947 PB - Wiley-Blackwell CY - Hoboken ER - TY - JOUR A1 - Tanski, George A1 - Couture, Nicole A1 - Lantuit, Hugues A1 - Eulenburg, Antje A1 - Fritz, Michael T1 - Eroding permafrost coasts release low amounts of dissolved organic carbon (DOC) from ground ice into the nearshore zone of the Arctic Ocean JF - Global biogeochemical cycles N2 - Ice-rich permafrost coasts in the Arctic are highly sensitive to climate warming and erode at a pace that exceeds the global average. Permafrost coasts deliver vast amounts of organic carbon into the nearshore zone of the Arctic Ocean. Numbers on flux exist for particulate organic carbon (POC) and total or soil organic carbon (TOC, SOC). However, they do not exist for dissolved organic carbon (DOC), which is known to be highly bioavailable. This study aims to estimate DOC stocks in coastal permafrost as well as the annual flux into the ocean. DOC concentrations in ground ice were analyzed along the ice-rich Yukon coast (YC) in the western Canadian Arctic. The annual DOC flux was estimated using available numbers for coast length, cliff height, annual erosion rate, and volumetric ice content in different stratigraphic horizons. Our results showed that DOC concentrations in ground ice range between 0.3 and 347.0mgL(-1) with an estimated stock of 13.63.0gm(-3) along the YC. An annual DOC flux of 54.90.9Mgyr(-1) was computed. These DOC fluxes are low compared to POC and SOC fluxes from coastal erosion or POC and DOC fluxes from Arctic rivers. We conclude that DOC fluxes from permafrost coasts play a secondary role in the Arctic carbon budget. However, this DOC is assumed to be highly bioavailable. We hypothesize that DOC from coastal erosion is important for ecosystems in the Arctic nearshore zones, particularly in summer when river discharge is low, and in areas where rivers are absent. KW - Arctic KW - permafrost KW - coastal erosion KW - biogeochemistry KW - carbon cycle Y1 - 2016 U6 - https://doi.org/10.1002/2015GB005337 SN - 0886-6236 SN - 1944-9224 VL - 30 SP - 1054 EP - 1068 PB - American Geophysical Union CY - Cambridge ER - TY - JOUR A1 - Cazelles, R. A1 - Lalaoui, N. A1 - Hartmann, Tobias A1 - Leimkühler, Silke A1 - Wollenberger, Ursula A1 - Antonietti, Markus A1 - Cosnier, S. T1 - Ready to use bioinformatics analysis as a tool to predict immobilisation strategies for protein direct electron transfer (DET) JF - Polymer : the international journal for the science and technology of polymers KW - Bioinformatic KW - Bioelectrocatalysis KW - Electron transfer KW - Dehydrogenase KW - Nicotinamide Y1 - 2016 U6 - https://doi.org/10.1016/j.bios.2016.04.078 SN - 0956-5663 SN - 1873-4235 VL - 85 SP - 90 EP - 95 PB - Elsevier CY - Oxford ER - TY - JOUR A1 - Roggenbuck, Dirk A1 - Borghi, Maria Orietta A1 - Somma, Valentina A1 - Buettner, Thomas A1 - Schierack, Peter A1 - Hanack, Katja A1 - Grossi, Claudia A1 - Bodio, Caterina A1 - Macor, Paolo A1 - von Landenberg, Philipp A1 - Boccellato, Francesco A1 - Mahler, Michael A1 - Meroni, Pier Luigi T1 - Antiphospholipid antibodies detected by line immunoassay differentiate among patients with antiphospholipid syndrome, with infections and asymptomatic carriers JF - IEEE transactions on geoscience and remote sensing N2 - Background: Antiphospholipid antibodies (aPL) can be detected in asymptomatic carriers and infectious patients. The aim was to investigate whether a novel line immunoassay (LIA) differentiates between antiphospholipid syndrome (APS) and asymptomatic aPL+ carriers or patients with infectious diseases (infectious diseases controls (IDC)). Methods: Sixty-one patients with APS (56 primary, 22/56 with obstetric events only, and 5 secondary), 146 controls including 24 aPL+ asymptomatic carriers and 73 IDC were tested on a novel hydrophobic solid phase coated with cardiolipin (CL), phosphatic acid, phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylinositol, phosphatidylserine, beta2-glycoprotein I (beta 2GPI), prothrombin, and annexin V. Samples were also tested by anti-CL and anti-beta 2GPI ELISAs and for lupus anticoagulant activity. Human monoclonal antibodies (humoAbs) against human beta 2GPI or PL alone were tested on the same LIA substrates in the absence or presence of human serum, purified human beta 2GPI or after CL-micelle absorption. Results: Comparison of LIA with the aPL-classification assays revealed good agreement for IgG/IgM a beta 2GPI and aCL. Anti-CL and anti-beta 2GPI IgG/IgM reactivity assessed by LIA was significantly higher in patients with APS versus healthy controls and IDCs, as detected by ELISA. IgG binding to CL and beta 2GPI in the LIA was significantly lower in aPL+ carriers and Venereal Disease Research Laboratory test (VDRL) + samples than in patients with APS. HumoAb against domain 1 recognized beta 2GPI bound to the LIA-matrix and in anionic phospholipid (PL) complexes. Absorption with CL micelles abolished the reactivity of a PL-specific humoAb but did not affect the binding of anti-beta 2GPI humoAbs. Conclusions: The LIA and ELISA have good agreement in detecting aPL in APS, but the LIA differentiates patients with APS from infectious patients and asymptomatic carriers, likely through the exposure of domain 1. KW - Antiphospholipid syndrome KW - Antiphospholipid antibody KW - Phospholipid binding proteins KW - Beta2-glycoprotein I KW - Line immunoassay Y1 - 2016 U6 - https://doi.org/10.1186/s13075-016-1018-x SN - 1478-6354 SN - 1478-6362 VL - 18 PB - BioMed Central CY - London ER - TY - JOUR A1 - Schmidt, Carsten A1 - Roediger, Stefan A1 - Gruner, Melanie A1 - Moncsek, Anja A1 - Stohwasser, Ralf A1 - Hanack, Katja A1 - Schierack, Peter A1 - Schroeder, Christian T1 - Multiplex localization of sequential peptide epitopes by use of a planar microbead chip JF - Analytica chimica acta : an international journal devoted to all branches of analytical chemistry N2 - Epitope mapping is crucial for the characterization of protein-specific antibodies. Commonly, small overlapping peptides are chemically synthesized and immobilized to determine the specific peptide sequence. In this study, we report the use of a fast and inexpensive planar microbead chip for epitope mapping. We developed a generic strategy for expressing recombinant peptide libraries instead of using expensive synthetic peptide libraries. A biotin moiety was introduced in vivo at a defined peptide position using biotin ligase. Peptides in crude Escherichia coli lysate were coupled onto streptavidin-coated microbeads by incubation, thereby avoiding tedious purification procedures. For read-out we used a multiplex planar microbead chip with size- and fluorescence-encoded microbead populations. For epitope mapping, up to 18 populations of peptide-loaded microbeads (at least 20 microbeads per peptide) displaying the primary sequence of a protein were analyzed simultaneously. If an epitope was recognized by an antibody, a secondary fluorescence-labeled antibody generated a signal that was quantified, and the mean value of all microbeads in the population was calculated. We mapped the epitopes for rabbit anti-PA28 gamma (proteasome activator 28 gamma) polyclonal serum, for a murine monoclonal antibody against PA28 gamma, and for a murine monoclonal antibody against the hamster polyoma virus major capsid protein VP1 as models. In each case, the identification of one distinct peptide sequence out of up to 18 sequences was possible. Using this approach, an epitope can be mapped multiparametrically within three weeks. (C) 2016 Elsevier B.V. All rights reserved. KW - Epitope mapping KW - In vivo biotinylation KW - Multiplexed assays KW - Microbeads KW - VideoScan technology Y1 - 2016 U6 - https://doi.org/10.1016/j.aca.2015.12.030 SN - 0003-2670 SN - 1873-4324 VL - 908 SP - 150 EP - 160 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Feoktistova, Natalia A1 - Rose, Jürgen A1 - Prokopovic, Vladimir Z. A1 - Vikulina, Anna S. A1 - Skirtach, Andre A1 - Volodkin, Dmitry T1 - Controlling the Vaterite CaCO3 Crystal Pores. Design of Tailor-Made Polymer Based Microcapsules by Hard Templating JF - Langmuir N2 - The spherical vaterite CaCO3 microcrystals are nowadays widely used as sacrificial templates for fabrication of various microcarriers made of biopolymers (e.g., proteins, nucleic acids, enzymes) due to porous structure and mild template elimination conditions. Here, we demonstrated for the first time that polymer microcarriers with tuned internal nanoarchitecture can be designed by employing the CaCO3 crystals of controlled porosity. The layer-by-layer deposition has been utilized to assemble shell-like (hollow) and matrix-like (filled) polymer capsules due to restricted and free polymer diffusion through the crystal pores, respectively. The crystal pore size in the range of few tens of nanometers can be adjusted without any additives by variation of the crystal preparation temperature in the range 745 degrees C. The temperature-mediated growth mechanism is explained by the Ostwald ripening of nanocrystallites forming the crystal secondary structure. Various techniques including SEM, AFM, CLSM, Raman microscopy, nitrogen adsorptiondesorption, and XRD have been employed for crystal and microcapsule analysis. A three-dimensional model is introduced to describe the crystal internal structure and predict the pore cutoff and available surface for the pore diffusing molecules. Inherent biocompatibility of CaCO3 and a possibility to scale the porosity in the size range of typical biomacromolecules make the CaCO3 crystals extremely attractive tools for template assisted designing tailor-made biopolymer-based architectures in 2D to 3D targeted at drug delivery and other bioapplications. Y1 - 2016 U6 - https://doi.org/10.1021/acs.langmuir.6b00717 SN - 0743-7463 VL - 32 SP - 4229 EP - 4238 PB - American Chemical Society CY - Washington ER - TY - JOUR A1 - Pinyou, Piyanut A1 - Ruff, Adrian A1 - Poeller, Sascha A1 - Alsaoub, Sabine A1 - Leimkühler, Silke A1 - Wollenberger, Ursula A1 - Schuhmann, Wolfgang T1 - Wiring of the aldehyde oxidoreductase PaoABC to electrode surfaces via entrapment in low potential phenothiazine-modified redox polymers JF - Bioelectrochemistry : an international journal devoted to electrochemical aspects of biology and biological aspects of electrochemistry ; official journal of the Bioelectrochemical Society N2 - Phenothiazine-modified redox hydrogels were synthesized and used for the wiring of the aldehyde oxidoreductase PaoABC to electrode surfaces. The effects of the pH value and electrode surface modification on the biocatalytic activity of the layers were studied in the presence of vanillin as the substrate. The enzyme electrodes were successfully employed as bioanodes in vanillin/O-2 biofuel cells in combination with a high potential bilirubin oxidase biocathode. Open circuit voltages of around 700 mV could be obtained in a two compartment biofuel cell setup. Moreover, the use of a rather hydrophobic polymer with a high degree of crosslinking sites ensures the formation of stable polymer/enzyme films which were successfully used as bioanode in membrane-less biofuel cells. (C) 2015 Elsevier B.V. All rights reserved. KW - Aldehyde oxidoreductase KW - Enzyme electrode KW - Redox polymer KW - Phenothiazine KW - Biosensor KW - Biofuel cell Y1 - 2016 U6 - https://doi.org/10.1016/j.bioelechem.2015.12.005 SN - 1567-5394 SN - 1878-562X VL - 109 SP - 24 EP - 30 PB - Elsevier CY - Lausanne ER - TY - JOUR A1 - Hartmann, Tobias A1 - Schrapers, Peer A1 - Utesch, Tillmann A1 - Nimtz, Manfred A1 - Rippers, Yvonne A1 - Dau, Holger A1 - Mroginski, Maria Andrea A1 - Haumann, Michael A1 - Leimkühler, Silke T1 - The Molybdenum Active Site of Formate Dehydrogenase Is Capable of Catalyzing C-H Bond Cleavage and Oxygen Atom Transfer Reactions JF - Biochemistry N2 - Formate dehydrogenases (FDHs) are capable of performing the reversible oxidation of formate and are enzymes of great interest for fuel cell applications and for the production of reduced carbon compounds as energy sources from CO2. Metal containing FDHs in general contain a highly conserved active site, comprising a molybdenum (or tungsten) center coordinated by two molybdopterin guanine dinucleotide molecules, a sulfido and a (seleno-)cysteine ligand, in addition to a histidine and arginine residue in the second coordination sphere. So far, the role of these amino acids in catalysis has not been studied in detail, because of the lack of suitable expression systems and the lability or oxygen sensitivity of the enzymes. Here, the roles of these active site residues is revealed using the Mo-containing FDH from Rhodobacter capsulatus. Our results show that the cysteine ligand at the Mo ion is displaced by the formate substrate during the reaction, the arginine has a direct role in substrate binding and stabilization, and the histidine elevates the pK(a) of the active site cysteine. We further found that in addition to reversible formate oxidation, the enzyme is further capable of reducing nitrate to nitrite. We propose a mechanistic scheme that combines both functionalities and provides important insights into the distinct mechanisms of C-H bond cleavage and oxygen atom transfer catalyzed by formate dehydrogenase. Y1 - 2016 U6 - https://doi.org/10.1021/acs.biochem.6b00002 SN - 0006-2960 VL - 55 SP - 2381 EP - 2389 PB - American Chemical Society CY - Washington ER - TY - JOUR A1 - Stein, F. A1 - Doering-Arjes, P. A1 - Fladung, Erik A1 - Brämick, Uwe A1 - Bendall, B. A1 - Schroeder, B. T1 - Downstream Migration of the European Eel (Anguilla Anguilla) in the Elbe River, Germany: Movement Patterns and the Potential Impact of Environmental Factors JF - River Research and Applications N2 - Recruitment of European eels (Anguilla anguilla) has declined to the extent that they have been added to the IUCN Red List of Threatened Species. Therefore, it is critical to ensure that eels complete their outward river migration in order to contribute to the available spawning stock. We conducted a 4-year (2007-2011) telemetry study to understand the migratory behaviour and potential impact of environmental factors on the eel during this critical life stage. Out of 399 female eels tagged with acoustic transmitters, only 28% demonstrated clear downstream migratory behaviour. Fifty-five percent were detected exhibiting no downstream migration behaviour and 17% were not detected at any monitoring station. Movement patterns of downstream-migrating (silver) eels were characterized by nocturnal activity and seasonal migration, with distinct peaks in autumn and spring. Migration was often discontinuous and exhibited phases of active locomotion and expanded stopovers. The most important determinants of movement activity were water temperature, cumulative precipitation and moonlight, although the significance varied by season and location in the river basin. Our results evidence a discontinuous, stepwise migration over an extended period. Furthermore, our findings indicate that migration success depends on holding duration prior to tagging and environmental predictors with varying importance depending on the season, as well as the locations of capture, tagging and release. Copyright (c) 2015 John Wiley & Sons, Ltd. KW - acoustic telemetry KW - fish migration KW - environmental trigger KW - generalized linear model KW - handling effect KW - discontinuous migration KW - Anguilla anguilla KW - seasonal migration Y1 - 2016 U6 - https://doi.org/10.1002/rra.2881 SN - 1535-1459 SN - 1535-1467 VL - 32 SP - 666 EP - 676 PB - Wiley-Blackwell CY - Hoboken ER - TY - JOUR A1 - van de Weijer, Steve A1 - Bijleveld, Catrien A1 - Huschek, Doreen T1 - Offending and mortality JF - Advances in life course research N2 - Background: Previous research has shown that offenders are at increased risk to die prematurely, but the etiology of this association is still unknown. Moreover, most previous studies use relatively short follow-up periods and do not take into account variation within the offender population with respect to frequency, timing and types of offenses. Method: Using conviction data for a number of families at high-risk of offending born on average in 1932, we study mortality in both offenders and non-offenders, from a similar socio-economic background, until 2007. We condition on life expectancy of the parents, age, gender, year of birth and marital status. We investigate associations between mortality and offending for different types of offenses: violent offenses, property offenses, weapons offenses, drugs offenses and driving under influence. Results: In general, offending sample members were not significantly more likely to have died than non offending sample members. Compared to the general population, however, both the offending and non offending sample members were at increased risk to die. Sample members who were convicted for driving under the influence of alcohol or weapons offenses were at increased risk to die prematurely compared to non-offending sample members. Conclusions: The relationship between offending in general and mortality is largely spurious. Limitations: The use of official conviction data might have influenced the results. (C) 2015 Elsevier Ltd. All rights reserved. KW - Mortality KW - Offending KW - Mechanisms KW - Survival KW - The Netherlands Y1 - 2016 U6 - https://doi.org/10.1016/j.alcr.2015.11.004 SN - 1569-4909 SN - 1879-6974 VL - 28 SP - 91 EP - 99 PB - Elsevier CY - Oxford ER - TY - JOUR A1 - Fer, Istem A1 - Tietjen, Britta A1 - Jeltsch, Florian T1 - High-resolution modelling closes the gap between data and model simulations for Mid-Holocene and present-day biomes of East Africa JF - Palaeogeography, palaeoclimatology, palaeoecology : an international journal for the geo-sciences N2 - East Africa hosts a striking diversity of terrestrial ecosystems, which vary both in space and time due to complex regional topography and a dynamic climate. The structure and functioning of these ecosystems under this environmental setting can be studied with dynamic vegetation models (DVMs) in a spatially explicit way. Yet, regional applications of DVMs to East Africa are rare and a comprehensive validation of such applications is missing. Here, we simulated the present-day and mid-Holocene vegetation of East Africa with the DVM, LPJ-GUESS and we conducted an exhaustive comparison of model outputs with maps of potential modern vegetation distribution, and with pollen records of local change through time. Overall, the model was able to reproduce the observed spatial patterns of East African vegetation. To see whether running the model at higher spatial resolutions (10′ × 10′) contribute to resolve the vegetation distribution better and have a better comparison scale with the observational data (i.e. pollen data), we run the model with coarser spatial resolution (0.5° × 0.5°) for the present-day as well. Both the area- and point-wise comparison showed that a higher spatial resolution allows to better describe spatial vegetation changes induced by the complex topography of East Africa. Our analysis of the difference between modelled mid-Holocene and modern-day vegetation showed that whether a biome shifts to another is best explained by both the amount of change in precipitation it experiences and the amount of precipitation it received originally. We also confirmed that tropical forest biomes were more sensitive to a decrease in precipitation compared to woodland and savanna biomes and that Holocene vegetation changes in East Africa were driven not only by changes in annual precipitation but also by changes in its seasonality. KW - Dynamic vegetation models KW - Biome KW - Mid-Holocene KW - Leaf area index KW - Climate change KW - East Africa Y1 - 2016 U6 - https://doi.org/10.1016/j.palaeo.2015.12.001 SN - 0031-0182 SN - 1872-616X VL - 444 SP - 144 EP - 151 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Orawetz, Tom A1 - Malinova, Irina A1 - Orzechowski, Slawomir A1 - Fettke, Jörg T1 - Reduction of the plastidial phosphorylase in potato (Solanum tuberosum L.) reveals impact on storage starch structure during growth at low temperature JF - Plant physiology and biochemistry : an official journal of the Federation of European Societies of Plant Physiology N2 - Tubers of potato (Solanum tuberosum L.), one of the most important crops, are a prominent example for an efficient production of storage starch. Nevertheless, the synthesis of this storage starch is not completely understood. The plastidial phosphorylase (Phol; EC 2.4.11) catalyzes the reversible transfer of glucosyl residues from glucose-1-phosphate to the non-reducing end of alpha-glucans with the release of orthophosphate. Thus, the enzyme is in principle able to act during starch synthesis. However, so far under normal growth conditions no alterations in tuber starch metabolism were observed. Based on analyses of other species and also from in vitro experiments with potato tuber slices it was supposed, that Phol has a stronger impact on starch metabolism, when plants grow under low temperature conditions. Therefore, we analyzed the starch content, granule size, as well as the internal structure of starch granules isolated from potato plants grown under low temperatures. Besides wild type, transgenic potato plants with a strong reduction in the Phol activity were analyzed. No significant alterations in starch content and granule size were detected. In contrast, when plants were cultivated at low temperatures the chain length distributions of the starch granules were altered. Thus, the granules contained more short glucan chains. That was not observed in the transgenic plants, revealing that Pho1 in wild type is involved in the formation of the short glucan chains, at least at low temperatures. (C) 2016 Elsevier Masson SAS. All rights reserved. KW - Potato KW - Solanum tuberosum L. KW - Plastidial phosphorylase KW - Starch synthase KW - Starch metabolism KW - Starch granule Y1 - 2016 U6 - https://doi.org/10.1016/j.plaphy.2016.01.013 SN - 0981-9428 VL - 100 SP - 141 EP - 149 PB - Elsevier CY - Paris ER - TY - JOUR A1 - Pfestorf, Hans A1 - Körner, Katrin A1 - Sonnemann, Ilja A1 - Wurst, Susanne A1 - Jeltsch, Florian T1 - Coupling experimental data with individual-based modelling reveals differential effects of root herbivory on grassland plant co-existence along a resource gradient JF - Journal of vegetation science N2 - QuestionThe empirical evidence of root herbivory effects on plant community composition and co-existence is contradictory. This originates from difficulties connected to below-ground research and confinement of experimental studies to a small range of environmental conditions. Here we suggest coupling experimental data with an individual-based model to overcome the limitations inherent in either approach. To demonstrate this, we investigated the consequences of root herbivory, as experimentally observed on individual plants, on plant competition and co-existence in a population and community context under different root herbivory intensities (RHI), fluctuating and constant root herbivore activity and grazing along a resource gradient. LocationBerlin, Germany, glasshouse; Potsdam, Germany, high performance cluster computer. MethodsThe well-established community model IBC-Grass was adapted to allow for a flexible species parameterization and to include annual species. Experimentally observed root herbivory effects on performance of eight common grassland plant species were incorporated into the model by altering plant growth rates. We then determined root herbivore effects on plant populations, competitive hierarchy and consequences for co-existence and community diversity. ResultsRoot herbivory reduced individual biomass, but temporal fluctuation allowed for compensation of herbivore effects. Reducing resource availability strongly shifted competitive hierarchies, with, however, more similar hierarchies along the gradient under root herbivory, pointing to reduced ecological species differences. Consequently, negative effects on co-existence and diversity prevailed, with the exception of a few positive effects on co-existence of selected species pairs. Temporal fluctuation alleviated but did not remove negative root herbivore effects, despite of the stronger influence of intra- compared to interspecific competition. Grazing in general augmented co-existence. Most interestingly, grazing interacted with RHI and resource availability by promoting positive effects of root herbivory. ConclusionsThrough integrating experimental data on the scale of individual plants with a simulation model we verified that root herbivory could affect plant competition with consequences for species co-existence. Our approach demonstrates the benefit that accrues when empirical and modelling approaches are brought more closely together, and that gathering data on distinct processes and under specific conditions, combined with appropriate models, can be used to answer challenging research questions in a more general way. KW - Above-/below-ground interactions KW - Below-ground resources KW - Competitive hierarchies KW - Grassland KW - Greenhouse experiment KW - Simulation experiment KW - Species co-existence KW - Wireworms Y1 - 2016 U6 - https://doi.org/10.1111/jvs.12357 SN - 1100-9233 SN - 1654-1103 VL - 27 SP - 269 EP - 282 PB - Wiley-Blackwell CY - Hoboken ER - TY - JOUR A1 - Jargosch, M. A1 - Kroeger, S. A1 - Gralinska, E. A1 - Klotz, Ulrike A1 - Fang, Z. A1 - Chen, W. A1 - Leser, U. A1 - Selbig, Joachim A1 - Groth, Detlef A1 - Baumgrass, Ria T1 - Data integration for identification of important transcription factors of STAT6-mediated cell fate decisions JF - Genetics and molecular research N2 - Data integration has become a useful strategy for uncovering new insights into complex biological networks. We studied whether this approach can help to delineate the signal transducer and activator of transcription 6 (STAT6)-mediated transcriptional network driving T helper (Th) 2 cell fate decisions. To this end, we performed an integrative analysis of publicly available RNA-seq data of Stat6-knockout mouse studies together with STAT6 ChIP-seq data and our own gene expression time series data during Th2 cell differentiation. We focused on transcription factors (TFs), cytokines, and cytokine receptors and delineated 59 positively and 41 negatively STAT6-regulated genes, which were used to construct a transcriptional network around STAT6. The network illustrates that important and well-known TFs for Th2 cell differentiation are positively regulated by STAT6 and act either as activators for Th2 cells (e.g., Gata3, Atf3, Satb1, Nfil3, Maf, and Pparg) or as suppressors for other Th cell subpopulations such as Th1 (e.g., Ar), Th17 (e.g., Etv6), or iTreg (e.g., Stat3 and Hifla) cells. Moreover, our approach reveals 11 TFs (e.g., Atf5, Creb3l2, and Asb2) with unknown functions in Th cell differentiation. This fact together with the observed enrichment of asthma risk genes among those regulated by STAT6 underlines the potential value of the data integration strategy used here. Thus, our results clearly support the opinion that data integration is a useful tool to delineate complex physiological processes. KW - Data integration KW - Th2 cells KW - Gene regulatory network KW - STAT6 KW - Transcription factors Y1 - 2016 U6 - https://doi.org/10.4238/gmr.15028493 SN - 1676-5680 VL - 15 PB - FUNPEC CY - Ribeirao Preto ER - TY - JOUR A1 - Ud-Din, Aziz A1 - Rauf, Mamoona A1 - Ghafoor, S. A1 - Khattak, M. N. K. A1 - Hameed, M. W. A1 - Shah, H. A1 - Jan, S. A1 - Muhammad, K. A1 - Rehman, A. A1 - Inamullah, T1 - Efficient use of artificial micro-RNA to downregulate the expression of genes at the post-transcriptional level in Arabidopsis thaliana JF - Genetics and molecular research N2 - Micro-RNAs are cellular components regulating gene expression at the post-transcription level. In the present study, artificial micro-RNAs were used to decrease the transcript level of two genes, AtExpA8 (encoding an expansin) and AHL25 (encoding an AT-hook motif nuclear localized protein) in Arabidopsis thaliana. The backbone of the Arabidopsis endogenous MIR319a micro-RNA was used in a site-directed mutagenesis approach for the generation of artificial micro-RNAs targeting two genes. The recombinant cassettes were expressed under the control of the CaMV 35S promoter in individual A. thaliana plants. Transgenic lines of the third generation were tested by isolating total RNA and by subsequent cDNA synthesis using oligo-dT18 primers and mRNAs as templates. The expression of the two target genes was checked through quantitative realtime polymerase chain reaction to confirm reduced transcript levels for AtExpA8 and AHL25. Downregulation of AtExpA8 resulted in the formation of short hypocotyls compared with those of the wild-type control in response to low pH and high salt concentration. This technology could be used to prevent the expression of exogenous and invading genes posing a threat to the normal cellular physiology of the host plant. KW - Artificial micro-RNA KW - Arabidopsis thaliana KW - qRT-PCR KW - AtExpA8 KW - AHL25 Y1 - 2016 U6 - https://doi.org/10.4238/gmr.15027439 SN - 1676-5680 VL - 15 PB - FUNPEC CY - Ribeirao Preto ER - TY - JOUR A1 - Kruse, Michaela A1 - Stein-Bachinger, Karin A1 - Gottwald, Frank A1 - Schmidt, Elisabeth A1 - Heinken, Thilo T1 - Influence of grassland management on the biodiversity of plants and butterflies on organic suckler cow farms JF - Tuexenia : Mitteilungen der Floristisch-Soziologischen Arbeitsgemeinschaft N2 - The intensification of agricultural practices has led to a severe decrease in grassland biodiversity. Although there is strong evidence that organic farming can reduce the negative impacts of land use, knowledge regarding the most beneficial management system for species richness on organic grasslands is still scarce. This study examines differences in the biodiversity of plants and butterflies on rotationally and continuously grazed pastures as well as on meadows cut twice per year on two large organic suckler cow farms in NE Germany. Vegetation and flower abundance, as factors likely to influence butterfly abundance and diversity, were compared and used to explain the differences. The data attained by vegetation assessments and monthly transect inspections from May to August were analyzed using descriptive statistics and nonparametric methods. The abiotic site conditions of the studied plots had more influence on plant species numbers than the management method. Dry and nutrient-poor areas (mainly poor types of Cynosurion) and undrained wet fens (Calthion) were important for phytodiversity, measured by the absolute number of species, indicator species for ecologically valuable grasslands and the Shannon Index. Meadows tended to have more indicator species than pastures, where small-scale special sites such as wet depressions were crucial for plant diversity. Butterfly diversity was very low, and 90% of the recorded butterflies were individuals of the generalist species Pieris napi. Butterfly abundance depended mainly on occurrence of specific habitat types and specific larval host plants. Supply of flowers was crucial only in certain time periods. Differences in butterfly abundance between the management systems could be explained by the site conditions of the studied grasslands. We conclude that meadows are more favorable to support ecologically valuable plant species; however, their extension is contradictory to the organic farming method of suckler cows maintained outside of stables. Rotationally grazed pastures could be a compromise that would enhance the temporal heterogeneity of flower abundance and vegetation structure. The plant diversity on pastures should be improved by less intensive grazing on special sites and plant species enrichment by means of hay transfer. For enhancing butterfly diversity we suggest to reduce land use intensity especially on poor soils. Considering the economic perspective of the farms, small parts of the agricultural area could be sufficient if connectivity to other suitable habitats is assured. Flower abundance and diversity of larval host plants could be promoted by high diversity of farming practices as well as preserving small uncut strips of meadows. KW - cattle grazing KW - continuous pasture KW - land use impact KW - lowland fen KW - meadow KW - organic farming KW - plant community KW - rotational pasture KW - species diversity KW - wet grassland Y1 - 2016 U6 - https://doi.org/10.14471/2016.56.006 SN - 0722-494X VL - 37 SP - 97 EP - 119 PB - Floristisch-Soziologische Arbeitsgemeinschaft CY - Göttingen ER - TY - JOUR A1 - Mao, Hailiang A1 - Nakamura, Moritaka A1 - Viotti, Corrado A1 - Grebe, Markus T1 - A Framework for Lateral Membrane Trafficking and Polar Tethering of the PEN3 ATP-Binding Cassette Transporter JF - Plant physiology : an international journal devoted to physiology, biochemistry, cellular and molecular biology, biophysics and environmental biology of plants N2 - The outermost cell layer of plants, the epidermis, and its outer (lateral) membrane domain facing the environment are continuously challenged by biotic and abiotic stresses. Therefore, the epidermis and the outer membrane domain provide important selective and protective barriers. However, only a small number of specifically outer membrane-localized proteins are known. Similarly, molecular mechanisms underlying the trafficking and the polar placement of outer membrane domain proteins require further exploration. Here, we demonstrate that ACTIN7 (ACT7) mediates trafficking of the PENETRATION3 (PEN3) outer membrane protein from the trans-Golgi network (TGN) to the plasma membrane in the root epidermis of Arabidopsis (Arabidopsis thaliana) and that actin function contributes to PEN3 endocytic recycling. In contrast to such generic ACT7-dependent trafficking from the TGN, the EXOCYST84b (EXO84b) tethering factor mediates PEN3 outer-membrane polarity. Moreover, precise EXO84b placement at the outer membrane domain itself requires ACT7 function. Hence, our results uncover spatially and mechanistically distinct requirements for ACT7 function during outer lateral membrane cargo trafficking and polarity establishment. They further identify an exocyst tethering complex mediator of outer lateral membrane cargo polarity. Y1 - 2016 U6 - https://doi.org/10.1104/pp.16.01252 SN - 0032-0889 SN - 1532-2548 VL - 172 SP - 2245 EP - 2260 PB - American Society of Plant Physiologists CY - Rockville ER - TY - JOUR A1 - Reinecke, J. A1 - Wulf, M. A1 - Baeten, Lander A1 - Brunet, J. A1 - Decocq, G. A1 - De Frenne, G. A1 - Diekmann, M. A1 - Graae, B. J. A1 - Heinken, Thilo A1 - Hermy, M. A1 - Jamoneau, A. A1 - Lenoir, J. A1 - Plue, J. A1 - Orczewska, A. A1 - Van Calster, H. A1 - Verheyen, Kris A1 - Naaf, T. T1 - Acido- and neutrophilic temperate forest plants display distinct shifts in ecological pH niche across north-western Europe JF - Ecography : pattern and diversity in ecology ; research papers forum N2 - Ecological niches of organisms vary across geographical space, but niche shift patterns between regions and the underlying mechanisms remain largely unexplored. We studied shifts in the pH niche of 42 temperate forest plant species across a latitudinal gradient from northern France to boreo-nemoral Sweden. We asked 1) whether species restrict their niches with increasing latitude as they reach their northern range margin (environmental constraints); 2) whether species expand their niches with increasing latitude as regional plant species richness decreases (competitive release); and 3) whether species shift their niche position toward more acidic sites with increasing latitude as the relative proportion of acidic soils increases (local adaptation). Based on 1458 vegetation plots and corresponding soil pH values, we modelled species response curves using Huisman-Olff-Fresco models. Four niche measures (width, position, left and right border) were compared among regions by randomization tests. We found that with increasing latitude, neutrophilic species tended to retreat from acidic sites, indicating that these species retreat to more favorable sites when approaching their range margin. Alternatively, these species might benefit from enhanced nitrogen deposition on formerly nutrient-poor, acidic sites in southern regions or lag behind in post-glacial recolonization of potential habitats in northern regions. Most acidophilic species extended their niche toward more base-rich sites with increasing latitude, indicating competitive release from neutrophilic species. Alternatively, acidophilic species might benefit from optimal climatic conditions in the north where some have their core distribution area. Shifts in the niche position suggested that local adaptation is of minor importance. We conclude that shifts in the pH niche of temperate forest plants are the rule, but the directions of the niche shifts and possible explanations vary. Our study demonstrates that differentiating between acidophilic and neutrophilic species is crucial to identify general patterns and underlying mechanisms. Y1 - 2016 U6 - https://doi.org/10.1111/ecog.02051 SN - 0906-7590 SN - 1600-0587 VL - 39 SP - 1164 EP - 1175 PB - Wiley-Blackwell CY - Hoboken ER - TY - JOUR A1 - Procter, Duncan S. A1 - Cottrell, Joan E. A1 - Watts, Kevin A1 - Hofreiter, Michael A1 - Robinson, Elva J. H. T1 - Does cooperation mean kinship between spatially discrete ant nests? JF - Ecology and evolution N2 - Eusociality is one of the most complex forms of social organization, characterized by cooperative and reproductive units termed colonies. Altruistic behavior of workers within colonies is explained by inclusive fitness, with indirect fitness benefits accrued by helping kin. Members of a social insect colony are expected to be more closely related to one another than they are to other conspecifics. In many social insects, the colony can extend to multiple socially connected but spatially separate nests (polydomy). Social connections, such as trails between nests, promote cooperation and resource exchange, and we predict that workers from socially connected nests will have higher internest relatedness than those from socially unconnected, and noncooperating, nests. We measure social connections, resource exchange, and internest genetic relatedness in the polydomous wood ant Formica lugubris to test whether (1) socially connected but spatially separate nests cooperate, and (2) high internest relatedness is the underlying driver of this cooperation. Our results show that socially connected nests exhibit movement of workers and resources, which suggests they do cooperate, whereas unconnected nests do not. However, we find no difference in internest genetic relatedness between socially connected and unconnected nest pairs, both show high kinship. Our results suggest that neighboring pairs of connected nests show a social and cooperative distinction, but no genetic distinction. We hypothesize that the loss of a social connection may initiate ecological divergence within colonies. Genetic divergence between neighboring nests may build up only later, as a consequence rather than a cause of colony separation. KW - colony organization KW - eusociality KW - Formica lugubris KW - kin selection KW - polydomy KW - social organization Y1 - 2016 U6 - https://doi.org/10.1002/ece3.2590 SN - 2045-7758 VL - 6 SP - 8846 EP - 8856 PB - Wiley-Blackwell CY - Hoboken ER -