@article{MetzvonOppenTielboerger2015, author = {Metz, Johannes and von Oppen, Jonathan and Tielb{\"o}rger, Katja}, title = {Parental environmental effects due to contrasting watering adapt competitive ability, but not drought tolerance, in offspring of a semi-arid annual Brassicaceae}, series = {The journal of ecology}, volume = {103}, journal = {The journal of ecology}, number = {4}, publisher = {Wiley-Blackwell}, address = {Hoboken}, issn = {0022-0477}, doi = {10.1111/1365-2745.12411}, pages = {990 -- 997}, year = {2015}, abstract = {Parental effects (PE) can be adaptive and improve offspring performance when parents and offspring experience similar environmental conditions. However, it is unknown whether adaptive PE exist also in habitats where such similarity is unlikely due to strong temporal variation. In particular, we do not know whether PE can adapt offspring to fluctuating levels of neighbour competition in such habitats. Here, we tested for adaptive PE in terms of two key environmental factors in a semi-arid annual system, competition and drought. While rainfall was stochastic in the study site, the competitive environment was partly predictable: higher plant densities followed after favourable (rainy) years due to high seed production. We therefore expected PE to adapt the offspring's competitive ability to these (predictable) fluctuations in plant densities, rather than to adapt the offspring's drought tolerance to the (unpredictable) occurrence of intensified drought. Parental plants of Biscutella didyma, an annual Brassicaceae, were raised under favourable watering and under drought conditions. Offspring performance was then tested under a full-factorial combination of two neighbour regimes and six watering levels in the glasshouse. Offspring of parents grown under favourable conditions were stronger competitors. This was associated with a small shift in phenology but not with higher parental seed provisioning. Offspring from parents grown under drought showed no improved drought tolerance. Moreover, no PE were detectable when offspring were grown without neighbours. Our results suggest a novel path of adaptive PE: higher competitive ability was induced in offspring that were more likely to experience high neighbour densities. Together with the lack of adaptive PE towards drought tolerance, this emphasizes that a correlation between parental and offspring environment is crucial for adaptive PE to evolve. Our results also call for the inclusion of competitive effects in future PE studies.Synthesis. This study demonstrates the important role of adaptive PE for plant fitness (regarding competition) but also their limits (regarding drought) in temporally variable environments, based on the predictability of the respective environmental factor.}, language = {en} } @article{DiGiacomoDiGiacomoKligeretal.2015, author = {Di Giacomo, Adrian S. and Di Giacomo, Alejandro G. and Kliger, Rafi and Reboreda, Juan C. and Tiedemann, Ralph and Mahler, Bettina}, title = {No evidence of genetic variation in microsatellite and mitochondrial DNA markers among remaining populations of the Strange-tailed Tyrant Alectrurus risora, an endangered grassland species}, series = {Bird conservation international}, volume = {25}, journal = {Bird conservation international}, number = {2}, publisher = {Cambridge Univ. Press}, address = {New York}, issn = {0959-2709}, doi = {10.1017/S0959270914000203}, pages = {127 -- 138}, year = {2015}, abstract = {The Strange-tailed Tyrant Alectrurus risora (Aves: Tyrannidae) is an endemic species of southern South American grasslands that suffered a 90\% reduction of its original distribution due to habitat transformation. This has led the species to be classified as globally Vulnerable. By the beginning of the last century, populations were partially migratory and moved south during the breeding season. Currently, the main breeding population inhabits the Ibera wetlands in the province of Corrientes, north-east Argentina, where it is resident all year round. There are two remaining small populations in the province of Formosa, north-east Argentina, and in southern Paraguay, which are separated from the main population by the Parana-Paraguay River and its continuous riverine forest habitat. The populations of Corrientes and Formosa are separated by 300 km and the grasslands between populations are non-continuous due to habitat transformation. We used mtDNA sequences and eight microsatellite loci to test if there were evidences of genetic isolation between Argentinean populations. We found no evidence of genetic structure between populations (Phi(ST) = 0.004, P = 0.32; Fst = 0.01, P = 0.06), which can be explained by either retained ancestral polymorphism or by dispersal between populations. We found no evidence for a recent demographic bottleneck in nuclear loci. Our results indicate that these populations could be managed as a single conservation unit on a regional scale. Conservation actions should be focused on preserving the remaining network of areas with natural grasslands to guarantee reproduction, dispersal and prevent further decline of populations.}, language = {en} } @article{ValentePhillimoreEtienne2015, author = {Valente, Luis M. and Phillimore, Albert B. and Etienne, Rampal S.}, title = {Equilibrium and non-equilibrium dynamics simultaneously operate in the Gal{\´a}pagos islands}, series = {Ecology letters}, volume = {18}, journal = {Ecology letters}, publisher = {Wiley-Blackwell}, address = {Oxford}, issn = {1461-0248}, doi = {10.1111/ele.12461}, pages = {844 -- 852}, year = {2015}, abstract = {Island biotas emerge from the interplay between colonisation, speciation and extinction and are often the scene of spectacular adaptive radiations. A common assumption is that insular diversity is at a dynamic equilibrium, but for remote islands, such as Hawaii or Gal{\´a}pagos, this idea remains untested. Here, we reconstruct the temporal accumulation of terrestrial bird species of the Gal{\´a}pagos using a novel phylogenetic method that estimates rates of biota assembly for an entire community. We show that species richness on the archipelago is in an ascending phase and does not tend towards equilibrium. The majority of the avifauna diversifies at a slow rate, without detectable ecological limits. However, Darwin's finches form an exception: they rapidly reach a carrying capacity and subsequently follow a coalescent-like diversification process. Together, these results suggest that avian diversity of remote islands is rising, and challenge the mutual exclusivity of the non-equilibrium and equilibrium ecological paradigms.}, language = {en} } @article{MuinodeBruijnPajoroetal.2015, author = {Mui{\~n}o, Jose M. and de Bruijn, Suzanne and Pajoro, Alice and Geuten, Koen and Vingron, Martin and Angenent, Gerco C. and Kaufmann, Kerstin}, title = {Evolution of DNA-Binding Sites of a Floral Master Regulatory Transcription Factor}, series = {Molecular biology and evolution : MBE}, volume = {33}, journal = {Molecular biology and evolution : MBE}, number = {1}, publisher = {Oxford University Press}, address = {Oxford}, issn = {1537-1719}, doi = {10.1093/molbev/msv210}, year = {2015}, abstract = {lower development is controlled by the action of key regulatory transcription factors of the MADS-domain family. The function of these factors appears to be highly conserved among species based on mutant phenotypes. However, the conservation of their downstream processes is much less well understood, mostly because the evolutionary turnover and variation of their DNA-binding sites (BSs) among plant species have not yet been experimentally determined. Here, we performed comparative ChIP (chromatin immunoprecipitation)-seq experiments of the MADS-domain transcription factor SEPALLATA3 (SEP3) in two closely related Arabidopsis species: Arabidopsis thaliana and A. lyrata which have very similar floral organ morphology. We found that BS conservation is associated with DNA sequence conservation, the presence of the CArG-box BS motif and on the relative position of the BS to its potential target gene. Differences in genome size and structure can explain that SEP3 BSs in A. lyrata can be located more distantly to their potential target genes than their counterparts in A. thaliana. In A. lyrata, we identified transposition as a mechanism to generate novel SEP3 binding locations in the genome. Comparative gene expression analysis shows that the loss/gain of BSs is associated with a change in gene expression. In summary, this study investigates the evolutionary dynamics of DNA BSs of a floral key-regulatory transcription factor and explores factors affecting this phenomenon.}, language = {en} } @article{KieferClaesNzayisengaetal.2015, author = {Kiefer, Christian S. and Claes, Andrea R. and Nzayisenga, Jean-Claude and Pietra, Stefano and Stanislas, Thomas and Ikeda, Yoshihisa and Grebe, Markus}, title = {Arabidopsis AIP1-2 restricted by WER-mediated patterning modulates planar polarity}, series = {Development}, journal = {Development}, number = {142}, doi = {doi: 10.1242/dev.111013}, pages = {151 -- 161}, year = {2015}, abstract = {The coordination of cell polarity within the plane of the tissue layer (planar polarity) is crucial for the development of diverse multicellular organisms. Small Rac/Rho-family GTPases and the actin cytoskeleton contribute to planar polarity formation at sites of polarity establishment in animals and plants. Yet, upstream pathways coordinating planar polarity differ strikingly between kingdoms. In the root of Arabidopsis thaliana, a concentration gradient of the phytohormone auxin coordinates polar recruitment of Rho-of-plant (ROP) to sites of polar epidermal hair initiation. However, little is known about cytoskeletal components and interactions that contribute to this planar polarity or about their relation to the patterning machinery. Here, we show that ACTIN7 (ACT7) represents a main actin isoform required for planar polarity of root hair positioning, interacting with the negative modulator ACTIN-INTERACTING PROTEIN1-2 (AIP1-2). ACT7, AIP1-2 and their genetic interaction are required for coordinated planar polarity of ROP downstream of ethylene signalling. Strikingly, AIP1-2 displays hair cell file-enriched expression, restricted by WEREWOLF (WER)-dependent patterning and modified by ethylene and auxin action. Hence, our findings reveal AIP1-2, expressed under control of the WER-dependent patterning machinery and the ethylene signalling pathway, as a modulator of actin-mediated planar polarity.}, language = {en} } @article{PietraLangGrebe2015, author = {Pietra, Stefano and Lang, Patricia and Grebe, Markus}, title = {SABRE is required for stabilization of root hair patterning in Arabidopsis thaliana}, series = {Physiologia Plantarum}, volume = {153}, journal = {Physiologia Plantarum}, number = {3}, doi = {DOI: 10.1111/ppl.12257}, pages = {440 -- 453}, year = {2015}, abstract = {Patterned differentiation of distinct cell types is essential for the development of multicellular organisms. The root epidermis of Arabidopsis thaliana is composed of alternating files of root hair and non-hair cells and represents a model system for studying the control of cell-fate acquisition. Epidermal cell fate is regulated by a network of genes that translate positional information from the underlying cortical cell layer into a specific pattern of differentiated cells. While much is known about the genes of this network, new players continue to be discovered. Here we show that the SABRE (SAB) gene, known to mediate microtubule organization, anisotropic cell growth and planar polarity, has an effect on root epidermal hair cell patterning. Loss of SAB function results in ectopic root hair formation and destabilizes the expression of cell fate and differentiation markers in the root epidermis, including expression of the WEREWOLF (WER) and GLABRA2 (GL2) genes. Double mutant analysis reveal that wer and caprice (cpc) mutants, defective in core components of the epidermal patterning pathway, genetically interact with sab. This suggests that SAB may act on epidermal patterning upstream of WER and CPC. Hence, we provide evidence for a role of SAB in root epidermal patterning by affecting cell-fate stabilization. Our work opens the door for future studies addressing SAB-dependent functions of the cytoskeleton during root epidermal patterning.}, language = {en} } @article{LamannaKirschbaumWauricketal.2015, author = {Lamanna, Francesco and Kirschbaum, Frank and Waurick, Isabelle and Dieterich, Christoph and Tiedemann, Ralph}, title = {Cross-tissue and cross-species analysis of gene expression in skeletal muscle and electric organ of African weakly-electric fish (Teleostei; Mormyridae)}, series = {BMC genomics}, volume = {16}, journal = {BMC genomics}, publisher = {BioMed Central}, address = {London}, issn = {1471-2164}, doi = {10.1186/s12864-015-1858-9}, pages = {17}, year = {2015}, abstract = {Background: African weakly-electric fishes of the family Mormyridae are able to produce and perceive weak electric signals (typically less than one volt in amplitude) owing to the presence of a specialized, muscle-derived electric organ (EO) in their tail region. Such electric signals, also known as Electric Organ Discharges (EODs), are used for objects/prey localization, for the identification of conspecifics, and in social and reproductive behaviour. This feature might have promoted the adaptive radiation of this family by acting as an effective pre-zygotic isolation mechanism. Despite the physiological and evolutionary importance of this trait, the investigation of the genetic basis of its function and modification has so far remained limited. In this study, we aim at: i) identifying constitutive differences in terms of gene expression between electric organ and skeletal muscle (SM) in two mormyrid species of the genus Campylomormyrus: C. compressirostris and C. tshokwe, and ii) exploring cross-specific patterns of gene expression within the two tissues among C. compressirostris, C. tshokwe, and the outgroup species Gnathonemus petersii. Results: Twelve paired-end (100 bp) strand-specific RNA-seq Illumina libraries were sequenced, producing circa 330 M quality-filtered short read pairs. The obtained reads were assembled de novo into four reference transcriptomes. In silico cross-tissue DE-analysis allowed us to identify 271 shared differentially expressed genes between EO and SM in C. compressirostris and C. tshokwe. Many of these genes correspond to myogenic factors, ion channels and pumps, and genes involved in several metabolic pathways. Cross-species analysis has revealed that the electric organ transcriptome is more variable in terms of gene expression levels across species than the skeletal muscle transcriptome. Conclusions: The data obtained indicate that: i) the loss of contractile activity and the decoupling of the excitation-contraction processes are reflected by the down-regulation of the corresponding genes in the electric organ's transcriptome; ii) the metabolic activity of the EO might be specialized towards the production and turn-over of membrane structures; iii) several ion channels are highly expressed in the EO in order to increase excitability; iv) several myogenic factors might be down-regulated by transcription repressors in the EO.}, language = {en} } @article{PaulMamonekeneVateretal.2015, author = {Paul, Christiane and Mamonekene, Victor and Vater, Marianne and Feulner, Philine G. D. and Engelmann, Jacob and Tiedemann, Ralph and Kirschbaum, Frank}, title = {Comparative histology of the adult electric organ among four species of the genus Campylomormyrus (Teleostei: Mormyridae)}, series = {Journal of comparative physiology : A, Neuroethology, sensory, neural, and behavioral physiology}, volume = {201}, journal = {Journal of comparative physiology : A, Neuroethology, sensory, neural, and behavioral physiology}, number = {4}, publisher = {Springer}, address = {New York}, issn = {0340-7594}, doi = {10.1007/s00359-015-0995-6}, pages = {357 -- 374}, year = {2015}, abstract = {The electric organ (EO) of weakly electric mormyrids consists of flat, disk-shaped electrocytes with distinct anterior and posterior faces. There are multiple species-characteristic patterns in the geometry of the electrocytes and their innervation. To further correlate electric organ discharge (EOD) with EO anatomy, we examined four species of the mormyrid genus Campylomormyrus possessing clearly distinct EODs. In C. compressirostris, C. numenius, and C. tshokwe, all of which display biphasic EODs, the posterior face of the electrocytes forms evaginations merging to a stalk system receiving the innervation. In C. tamandua that emits a triphasic EOD, the small stalks of the electrocyte penetrate the electrocyte anteriorly before merging on the anterior side to receive the innervation. Additional differences in electrocyte anatomy among the former three species with the same EO geometry could be associated with further characteristics of their EODs. Furthermore, in C. numenius, ontogenetic changes in EO anatomy correlate with profound changes in the EOD. In the juvenile the anterior face of the electrocyte is smooth, whereas in the adult it exhibits pronounced surface foldings. This anatomical difference, together with disparities in the degree of stalk furcation, probably contributes to the about 12 times longer EOD in the adult.}, language = {en} } @article{KoesslHechavarriaVossetal.2015, author = {K{\"o}ssl, Manfred and Hechavarria, Julio and Voss, Cornelia and Schaefer, Markus and Vater, Marianne}, title = {Bat auditory cortex - model for general mammalian auditory computation or special design solution for active time perception?}, series = {European journal of neuroscience}, volume = {41}, journal = {European journal of neuroscience}, number = {5}, publisher = {Wiley-Blackwell}, address = {Hoboken}, issn = {0953-816X}, doi = {10.1111/ejn.12801}, pages = {518 -- 532}, year = {2015}, abstract = {Audition in bats serves passive orientation, alerting functions and communication as it does in other vertebrates. In addition, bats have evolved echolocation for orientation and prey detection and capture. This put a selective pressure on the auditory system in regard to echolocation-relevant temporal computation and frequency analysis. The present review attempts to evaluate in which respect the processing modules of bat auditory cortex (AC) are a model for typical mammalian AC function or are designed for echolocation-unique purposes. We conclude that, while cortical area arrangement and cortical frequency processing does not deviate greatly from that of other mammals, the echo delay time-sensitive dorsal cortex regions contain special designs for very powerful time perception. Different bat species have either a unique chronotopic cortex topography or a distributed salt-and-pepper representation of echo delay. The two designs seem to enable similar behavioural performance.}, language = {en} } @article{KraemerRavindranZaqoutetal.2015, author = {Kr{\"a}mer, Nadine and Ravindran, Ethiraj and Zaqout, Sami and Neubert, Gerda and Schindler, Detlev and Ninnemann, Olaf and Gr{\"a}f, Ralph and Seiler, Andrea E. M. and Kaindl, Angela M.}, title = {Loss of CDK5RAP2 affects neural but not non-neural mESC differentiation into cardiomyocytes}, series = {Cell cycle}, volume = {14}, journal = {Cell cycle}, number = {13}, publisher = {Taylor \& Francis Group}, address = {Philadelphia}, issn = {1538-4101}, doi = {10.1080/15384101.2015.1044169}, pages = {2044 -- 2057}, year = {2015}, abstract = {Biallelic mutations in the gene encoding centrosomal CDK5RAP2 lead to autosomal recessive primary microcephaly (MCPH), a disorder characterized by pronounced reduction in volume of otherwise architectonical normal brains and intellectual deficit. The current model for the microcephaly phenotype in MCPH invokes a premature shift from symmetric to asymmetric neural progenitor-cell divisions with a subsequent depletion of the progenitor pool. The isolated neural phenotype, despite the ubiquitous expression of CDK5RAP2, and reports of progressive microcephaly in individual MCPH cases prompted us to investigate neural and non-neural differentiation of Cdk5rap2-depleted and control murine embryonic stem cells (mESC). We demonstrate an accumulating proliferation defect of neurally differentiating Cdk5rap2-depleted mESC and cell death of proliferative and early postmitotic cells. A similar effect does not occur in non-neural differentiation into beating cardiomyocytes, which is in line with the lack of non-central nervous system features in MCPH patients. Our data suggest that MCPH is not only caused by premature differentiation of progenitors, but also by reduced propagation and survival of neural progenitors.}, language = {en} } @article{GraefBatsiosMeyer2015, author = {Gr{\"a}f, Ralph and Batsios, Petros and Meyer, Irene}, title = {Evolution of centrosomes and the nuclear lamina: Amoebozoan assets}, series = {European journal of cell biology}, volume = {94}, journal = {European journal of cell biology}, number = {6}, publisher = {Elsevier}, address = {Jena}, issn = {0171-9335}, doi = {10.1016/j.ejcb.2015.04.004}, pages = {249 -- 256}, year = {2015}, abstract = {The current eukaryotic tree of life groups most eukaryotes into one of five supergroups, the Opisthokonta, Amoebozoa, Archaeplastida, Excavata and SAR (Stramenopile, Alveolata, Rhizaria). Molecular and comparative morphological analyses revealed that the last eukaryotic common ancestor (LECA) already contained a rather sophisticated equipment of organelles including a mitochondrion, an endomembrane system, a nucleus with a lamina, a microtubule-organizing center (MTOC), and a flagellar apparatus. Recent studies of MTOCs, basal bodies/centrioles, and nuclear envelope organization of organisms in different supergroups have clarified our picture of how the nucleus and MTOCs co-evolved from LECA to extant eukaryotes. In this review we summarize these findings with special emphasis on valuable contributions of research on a lamin-like protein, nuclear envelope proteins, and the MTOC in the amoebozoan model organism Dictyostelium discoideum. (C) 2015 Elsevier GmbH. All rights reserved.}, language = {en} } @article{SeebensEsslDawsonetal.2015, author = {Seebens, Hanno and Essl, Franz and Dawson, Wayne and Fuentes, Nicol and Moser, Dietmar and Pergl, Jan and Pysek, Petr and van Kleunen, Mark and Weber, Ewald and Winter, Marten and Blasius, Bernd}, title = {Global trade will accelerate plant invasions in emerging economies under climate change}, series = {Global change biology}, volume = {21}, journal = {Global change biology}, number = {11}, publisher = {Wiley-Blackwell}, address = {Hoboken}, issn = {1354-1013}, doi = {10.1111/gcb.13021}, pages = {4128 -- 4140}, year = {2015}, abstract = {Trade plays a key role in the spread of alien species and has arguably contributed to the recent enormous acceleration of biological invasions, thus homogenizing biotas worldwide. Combining data on 60-year trends of bilateral trade, as well as on biodiversity and climate, we modeled the global spread of plant species among 147 countries. The model results were compared with a recently compiled unique global data set on numbers of naturalized alien vascular plant species representing the most comprehensive collection of naturalized plant distributions currently available. The model identifies major source regions, introduction routes, and hot spots of plant invasions that agree well with observed naturalized plant numbers. In contrast to common knowledge, we show that the 'imperialist dogma,' stating that Europe has been a net exporter of naturalized plants since colonial times, does not hold for the past 60 years, when more naturalized plants were being imported to than exported from Europe. Our results highlight that the current distribution of naturalized plants is best predicted by socioeconomic activities 20 years ago. We took advantage of the observed time lag and used trade developments until recent times to predict naturalized plant trajectories for the next two decades. This shows that particularly strong increases in naturalized plant numbers are expected in the next 20 years for emerging economies in megadiverse regions. The interaction with predicted future climate change will increase invasions in northern temperate countries and reduce them in tropical and (sub) tropical regions, yet not by enough to cancel out the trade-related increase.}, language = {en} } @article{TedderCarleialGolebiewskaetal.2015, author = {Tedder, Andrew and Carleial, Samuel and Golebiewska, Martyna and Kappel, Christian and Shimizu, Kentaro K. and Stift, Marc}, title = {Evolution of the Selfing Syndrome in Arabis alpina (Brassicaceae)}, series = {PLoS one}, volume = {10}, journal = {PLoS one}, number = {6}, publisher = {PLoS}, address = {San Fransisco}, issn = {1932-6203}, doi = {10.1371/journal.pone.0126618}, pages = {17}, year = {2015}, abstract = {Introduction The transition from cross-fertilisation (outcrossing) to self-fertilisation (selfing) frequently coincides with changes towards a floral morphology that optimises self-pollination, the selfing syndrome. Population genetic studies have reported the existence of both outcrossing and selfing populations in Arabis alpina (Brassicaceae), which is an emerging model species for studying the molecular basis of perenniality and local adaptation. It is unknown whether its selfing populations have evolved a selfing syndrome. Methods Using macro-photography, microscopy and automated cell counting, we compared floral syndromes (size, herkogamy, pollen and ovule numbers) between three outcrossing populations from the Apuan Alps and three selfing populations from the Western and Central Alps (Maritime Alps and Dolomites). In addition, we genotyped the plants for 12 microsatellite loci to confirm previous measures of diversity and inbreeding coefficients based on allozymes, and performed Bayesian clustering. Results and Discussion Plants from the three selfing populations had markedly smaller flowers, less herkogamy and lower pollen production than plants from the three outcrossing populations, whereas pistil length and ovule number have remained constant. Compared to allozymes, microsatellite variation was higher, but revealed similar patterns of low diversity and high Fis in selfing populations. Bayesian clustering revealed two clusters. The first cluster contained the three outcrossing populations from the Apuan Alps, the second contained the three selfing populations from the Maritime Alps and Dolomites. Conclusion We conclude that in comparison to three outcrossing populations, three populations with high selfing rates are characterised by a flower morphology that is closer to the selfing syndrome. The presence of outcrossing and selfing floral syndromes within a single species will facilitate unravelling the genetic basis of the selfing syndrome, and addressing which selective forces drive its evolution.}, language = {en} } @article{PatheNeuschaeferRubeNeuschaeferRubeGenzetal.2015, author = {Pathe-Neuschaefer-Rube, Andrea and Neuschaefer-Rube, Frank and Genz, Lara and P{\"u}schel, Gerhard Paul}, title = {Botulinum Neurotoxin Dose-Dependently Inhibits Release of Neurosecretory Vesicle-Targeted Luciferase from Neuronal Cells}, series = {Alternatives to animal experimentation : ALTEX ; a journal for new paths in biomedical science}, volume = {32}, journal = {Alternatives to animal experimentation : ALTEX ; a journal for new paths in biomedical science}, number = {4}, publisher = {Springer}, address = {Heidelberg}, issn = {1868-596X}, pages = {297 -- 306}, year = {2015}, abstract = {Botulinum toxin is a bacterial toxin that inhibits neurotransmitter release from neurons and thereby causes a flaccid paralysis. It is used as drug to treat a number of serious ailments and, more frequently, for aesthetic medical interventions. Botulinum toxin for pharmacological applications is isolated from bacterial cultures. Due to partial denaturation of the protein, the specific activity of these preparations shows large variations. Because of its extreme potential toxicity, pharmacological preparations must be carefully tested for their activity. For the current gold standard, the mouse lethality assay, several hundred thousand mice are killed per year. Alternative methods have been developed that suffer from one or more of the following deficits: In vitro enzyme assays test only the activity of the catalytic subunit of the toxin. Enzymatic and cell based immunological assays are specific for just one of the different serotypes. The current study takes a completely different approach that overcomes these limitations: Neuronal cell lines were stably transfected with plasmids coding for luciferases of different species, which were N-terminally tagged with leader sequences that redirect the luciferase into neuro-secretory vesicles. From these vesicles, luciferases were released upon depolarization of the cells. The depolarization-dependent release was efficiently inhibited by botulinum toxin in a concentration range (1 to 100 pM) that is used in pharmacological preparations. The new assay might thus be an alternative to the mouse lethality assay and the immunological assays already in use.}, language = {en} } @article{CamargodosReisRiccardiTeixeiraRibeiroetal.2015, author = {Camargo, Rodolfo Gonzalez and dos Reis Riccardi, Daniela Mendes and Teixeira Ribeiro, Henrique Quintas and Carnevali Junior, Luiz Carlos and de Matos-Neto, Emidio Marques and Enjiu, Lucas and Neves, Rodrigo Xavier and Carola Correia Lima, Joanna Darck and Figueredo, Raquel Galvao and Martins de Alcantara, Paulo Sergio and Maximiano, Linda and Otoch, Jose and Batista Jr., Miguel Luiz and P{\"u}schel, Gerhard Paul and Seelaender, Marilia}, title = {NF-kappa Bp65 and Expression of Its Pro-Inflammatory Target Genes Are Upregulated in the Subcutaneous Adipose Tissue of Cachectic Cancer Patients}, series = {Nutrients}, volume = {7}, journal = {Nutrients}, number = {6}, publisher = {MDPI}, address = {Basel}, issn = {2072-6643}, doi = {10.3390/nu7064465}, pages = {4465 -- 4479}, year = {2015}, abstract = {Cancer cachexia, of which the most notable symptom is severe and rapid weight loss, is present in the majority of patients with advanced cancer. Inflammatory mediators play an important role in the development of cachexia, envisaged as a chronic inflammatory syndrome. The white adipose tissue (WAT) is one of the first compartments affected in cancer cachexia and suffers a high rate of lipolysis. It secretes several cytokines capable of directly regulating intermediate metabolism. A common pathway in the regulation of the expression of pro-inflammatory cytokines in WAT is the activation of the nuclear transcription factor kappa-B (NF-B). We have examined the gene expression of the subunits NF-Bp65 and NF-Bp50, as well as NF-Bp65 and NF-Bp50 binding, the gene expression of pro-inflammatory mediators under NF-B control (IL-1, IL-6, INF-, TNF-, MCP-1), and its inhibitory protein, nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor, alpha (IB-). The observational study involved 35 patients (control group, n = 12 and cancer group, n = 23, further divided into cachectic and non-cachectic). NF-Bp65 and its target genes expression (TNF-, IL-1, MCP-1 and IB-) were significantly higher in cachectic cancer patients. Moreover, NF-Bp65 gene expression correlated positively with the expression of its target genes. The results strongly suggest that the NF-B pathway plays a role in the promotion of WAT inflammation during cachexia.}, language = {en} } @article{NeuschaeferRubeSchraplauScheweetal.2015, author = {Neuschaefer-Rube, Frank and Schraplau, Anne and Schewe, Bettina and Lieske, Stefanie and Kruetzfeldt, Julia-Mignon and Ringel, Sebastian and Henkela, Janin and Birkenfeld, Andreas L. and P{\"u}schel, Gerhard Paul}, title = {Arylhydrocarbon receptor-dependent mIndy (SIc13a5) induction as possible contributor to benzo[a]pyrene-induced lipid accumulation in hepatocytes}, series = {Toxicology}, volume = {337}, journal = {Toxicology}, publisher = {Elsevier}, address = {Clare}, issn = {0300-483X}, doi = {10.1016/j.tox.2015.08.007}, pages = {1 -- 9}, year = {2015}, abstract = {Non-alcoholic fatty liver disease is a growing problem in industrialized and developing countries. Hepatic lipid accumulation is the result of an imbalance between fatty acid uptake, fatty acid de novo synthesis, beta-oxidation and secretion of triglyceride-rich lipoproteins from the hepatocyte. A central regulator of hepatic lipid metabolism is cytosolic citrate that can either be derived from the mitochondrium or be taken up from the blood via the plasma membrane sodium citrate transporter NaCT, the product of the mammalian INDY gene (SLC13A5). mINDY ablation protects against diet-induced steatosis whereas mINDY expression is increased in patients with hepatic steatosis. Diet-induced hepatic steatosis is also enhanced by activation of the arylhyrocarbon receptor (AhR) both in humans and animal models. Therefore, the hypothesis was tested whether the mINDY gene might be a target of the AhR. In accordance with such a hypothesis, the AhR activator benzo[a]pyrene induced the mINDY expression in primary cultures of rat hepatocytes in an AhR-dependent manner. This induction resulted in an increased citrate uptake and citrate incorporation into lipids which probably was further enhanced by the benzo[a]pyrene-dependent induction of key enzymes of fatty acid synthesis. A potential AhR binding site was identified in the mINDY promoter that appears to be conserved in the human promoter. Elimination or mutation of this site largely abolished the activation of the mINDY promoter by benzo[a]pyrene. This study thus identified the mINDY as an AhR target gene. AhR-dependent induction of the mINDY gene might contribute to the development of hepatic steatosis. (C) 2015 Elsevier Ireland Ltd. All rights reserved.}, language = {en} } @article{ChoiKlostermanKummeretal.2015, author = {Choi, Young-Joon and Klosterman, Steven J. and Kummer, Volker and Voglmayr, Hermann and Shin, Hyeon-Dong and Thines, Marco}, title = {Multi-locus tree and species tree approaches toward resolving a complex clade of downy mildews (Straminipila, Oomycota), including pathogens of beet and spinach}, series = {Molecular phylogenetics and evolution}, volume = {86}, journal = {Molecular phylogenetics and evolution}, publisher = {Elsevier}, address = {San Diego}, issn = {1055-7903}, doi = {10.1016/j.ympev.2015.03.003}, pages = {24 -- 34}, year = {2015}, abstract = {Accurate species determination of plant pathogens is a prerequisite for their control and quarantine, and further for assessing their potential threat to crops. The family Peronosporaceae (Straminipila; Oomycota) consists of obligate biotrophic pathogens that cause downy mildew disease on angiosperms, including a large number of cultivated plants. In the largest downy mildew genus Peronospora, a phylogenetically complex clade includes the economically important downy mildew pathogens of spinach and beet, as well as the type species of the genus Peronospora. To resolve this complex clade at the species level and to infer evolutionary relationships among them, we used multi-locus phylogenetic analysis and species tree estimation. Both approaches discriminated all nine currently accepted species and revealed four previously unrecognized lineages, which are specific to a host genus or species. This is in line with a narrow species concept, i.e. that a downy mildew species is associated with only a particular host plant genus or species. Instead of applying the dubious name Peronospora farinosa, which has been proposed for formal rejection, our results provide strong evidence that Peronospora schachtii is an independent species from lineages on Atriplex and apparently occurs exclusively on Beta vulgaris. The members of the clade investigated, the Peronospora rumicis clade, associate with three different host plant families, Amaranthaceae, Caryophyllaceae, and Polygonaceae, suggesting that they may have speciated following at least two recent inter-family host shifts, rather than contemporary cospeciation with the host plants. (C) 2015 Elsevier Inc. All rights reserved.}, language = {en} } @article{MeissnerSteinhauserDittmannThuenemann2015, author = {Meissner, Sven and Steinhauser, Dirk and Dittmann-Th{\"u}nemann, Elke}, title = {Metabolomic analysis indicates a pivotal role of the hepatotoxin microcystin in high light adaptation of Microcystis}, series = {Environmental microbiology}, volume = {17}, journal = {Environmental microbiology}, number = {5}, publisher = {Wiley-Blackwell}, address = {Hoboken}, issn = {1462-2912}, doi = {10.1111/1462-2920.12565}, pages = {1497 -- 1509}, year = {2015}, abstract = {Microcystis is a freshwater cyanobacterium frequently forming nuisance blooms in the summer months. The genus belongs to the predominant producers of the potent hepatotoxin microcystin. The success of Microcystis and its remarkable resistance to high light conditions are not well understood. Here, we have compared the metabolic response of Microcystis aeruginosaPCC7806, its microcystin-deficient mcyB mutant (Mut) and the cyanobacterial model organism SynechocystisPCC6803 to high light exposure of 250molphotonsm(-2)s(-1) using GC/MS-based metabolomics. Microcystis wild type and Mut show pronounced differences in their metabolic reprogramming upon high light. Seventeen percent of the detected metabolites showed significant differences between the two genotypes after high light exposure. Whereas the microcystin-producing wild type shows a faster accumulation of glycolate upon high light illumination, loss of microcystin leads to an accumulation of general stress markers such as trehalose and sucrose. The study further uncovers differences in the high light adaptation of the bloom-forming cyanobacterium Microcystis and the model cyanobacterium Synechocystis. Most notably, Microcystis invests more into carbon reserves such as glycogen after high light exposure. Our data shed new light on the lifestyle of bloom-forming cyanobacteria, the role of the widespread toxin microcystin and the metabolic diversity of cyanobacteria.}, language = {en} } @article{HuVoellerSussmuthetal.2015, author = {Hu, Chenlin and V{\"o}ller, Ginka and Sussmuth, Roderich and Dittmann-Th{\"u}nemann, Elke and Kehr, Jan-Christoph}, title = {Functional assessment of mycosporine-like amino acids in Microcystis aeruginosa strain PCC 7806}, series = {Environmental microbiology}, volume = {17}, journal = {Environmental microbiology}, number = {5}, publisher = {Wiley-Blackwell}, address = {Hoboken}, issn = {1462-2912}, doi = {10.1111/1462-2920.12577}, pages = {1548 -- 1559}, year = {2015}, abstract = {The biological role of the widespread mycosporine-like amino acids (MAAs) in cyanobacteria is under debate. Here, we have constructed and characterized two mutants impaired in MAA biosynthesis in the bloom-forming cyanobacterium Microcystis aeruginosaPCC 7806. We could identify shinorine as the sole MAA type of the strain, which is exclusively located in the extracellular matrix. Bioinformatic studies as wells as polymerase chain reaction screening revealed that the ability to produce MAAs is sporadically distributed within the genus. Growth experiments and reactive oxygen species quantification with wild-type and mutant strains did not support a role of shinorine in protection against UV or other stress conditions in M.aeruginosaPCC 7806. The shinorine content per dry weight of cells as well as transcription of the mys gene cluster was not significantly elevated in response to UV-A, UV-B or any other stress condition tested. Remarkably, both mutants exhibited pronounced morphological changes compared with the wild type. We observed an increased accumulation and an enhanced hydrophobicity of the extracellular matrix. Our study suggests that MAAs in Microcystis play a negligible role in protection against UV radiation but might be a strain-specific trait involved in extracellular matrix formation and cell-cell interaction.}, language = {en} } @article{VenailGrossOakleyetal.2015, author = {Venail, Patrick and Gross, Kevin and Oakley, Todd H. and Narwani, Anita and Allan, Eric and Flombaum, Pedro and Isbell, Forest and Joshi, Jasmin Radha and Reich, Peter B. and Tilman, David and van Ruijven, Jasper and Cardinale, Bradley J.}, title = {Species richness, but not phylogenetic diversity, influences community biomass production and temporal stability in a re-examination of 16 grassland biodiversity studies}, series = {Functional ecology : an official journal of the British Ecological Society}, volume = {29}, journal = {Functional ecology : an official journal of the British Ecological Society}, number = {5}, publisher = {Wiley-Blackwell}, address = {Hoboken}, issn = {0269-8463}, doi = {10.1111/1365-2435.12432}, pages = {615 -- 626}, year = {2015}, abstract = {Hundreds of experiments have now manipulated species richness (SR) of various groups of organisms and examined how this aspect of biological diversity influences ecosystem functioning. Ecologists have recently expanded this field to look at whether phylogenetic diversity (PD) among species, often quantified as the sum of branch lengths on a molecular phylogeny leading to all species in a community, also predicts ecological function. Some have hypothesized that phylogenetic divergence should be a superior predictor of ecological function than SR because evolutionary relatedness represents the degree of ecological and functional differentiation among species. But studies to date have provided mixed support for this hypothesis. Here, we reanalyse data from 16 experiments that have manipulated plant SR in grassland ecosystems and examined the impact on above-ground biomass production over multiple time points. Using a new molecular phylogeny of the plant species used in these experiments, we quantified how the PD of plants impacts average community biomass production as well as the stability of community biomass production through time. Using four complementary analyses, we show that, after statistically controlling for variation in SR, PD (the sum of branches in a molecular phylogenetic tree connecting all species in a community) is neither related to mean community biomass nor to the temporal stability of biomass. These results run counter to past claims. However, after controlling for SR, PD was positively related to variation in community biomass over time due to an increase in the variances of individual species, but this relationship was not strong enough to influence community stability. In contrast to the non-significant relationships between PD, biomass and stability, our analyses show that SR per se tends to increase the mean biomass production of plant communities, after controlling for PD. The relationship between SR and temporal variation in community biomass was either positive, non-significant or negative depending on which analysis was used. However, the increases in community biomass with SR, independently of PD, always led to increased stability. These results suggest that PD is no better as a predictor of ecosystem functioning than SR.Synthesis. Our study on grasslands offers a cautionary tale when trying to relate PD to ecosystem functioning suggesting that there may be ecologically important trait and functional variation among species that is not explained by phylogenetic relatedness. Our results fail to support the hypothesis that the conservation of evolutionarily distinct species would be more effective than the conservation of SR as a way to maintain productive and stable communities under changing environmental conditions.}, language = {en} }