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    Growing Research Networks on Mycorrhizae for Mutual Benefits 

    Ferlian, Olga; Biere, Arjen; Bonfante, Paola; Buscot, François; Eisenhauer, Nico; Fernandez, Ivan; Hause, Bettina; Herrmann, Sylvie; Krajinski-Barth, Franziska; Meier, Ina C.; et al.
    Pozo, Maria J.Rasmann, SergioRillig, Matthias C.Tarkka, Mika T.van Dam, Nicole M.Wagg, CameronMartinez-Medina, Ainhoa
    Trends in Plant Science 2018; 23(11) p.975-984
    Research on mycorrhizal interactions has traditionally developed into separate disciplines addressing different organizational levels. This separation has led to an incomplete understanding of mycorrhizal functioning. Integration of mycorrhiza research at different scales is needed to understand the mechanisms underlying the context dependency of mycorrhizal associations, and to use mycorrhizae for solving environmental issues. Here, we provide a road map for the integration of mycorrhiza research into a unique framework that spans genes to ecosystems. Using two key topics, we identify parallels in mycorrhiza research at different organizational levels. Based on two current projects, we show how scientific integration creates synergies, and discuss future directions. Only by overcoming disciplinary boundaries, we will achieve a more comprehensive understanding of the functioning of mycorrhizal associations.
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    MYB72-dependent coumarin exudation shapes root microbiome assembly to promote plant health 

    Stringlis, Ioannis A.; Yu, Ke; Feussner, Kirstin; de Jonge, Ronnie; Van Bentum, Sietske; Van Verk, Marcel C.; Berendsen, Roeland L.; Bakker, Peter A. H. M.; Feussner, Ivo; Pieterse, Corné M. J.
    Proceedings of the National Academy of Sciences of the United States of America 2018; 115(22) p.E5213-E5222
    Plant roots nurture a tremendous diversity of microbes via exudation of photosynthetically fixed carbon sources. In turn, probiotic members of the root microbiome promote plant growth and protect the host plant against pathogens and pests. In the Arabidopsis thaliana-Pseudomonas simiae WCS417 model system the root-specific transcription factor MYB72 and the MYB72-controlled β-glucosidase BGLU42 emerged as important regulators of beneficial rhizobacteria-induced systemic resistance (ISR) and iron-uptake responses. MYB72 regulates the biosynthesis of iron-mobilizing fluorescent phenolic compounds, after which BGLU42 activity is required for their excretion into the rhizosphere. Metabolite fingerprinting revealed the antimicrobial coumarin scopoletin as a dominant metabolite that is produced in the roots and excreted into the rhizosphere in a MYB72- and BGLU42-dependent manner. Shotgun-metagenome sequencing of root-associated microbiota of Col-0, myb72, and the scopoletin biosynthesis mutant f6'h1 showed that scopoletin selectively impacts the assembly of the microbial community in the rhizosphere. We show that scopoletin selectively inhibits the soil-borne fungal pathogens Fusarium oxysporum and Verticillium dahliae, while the growth-promoting and ISR-inducing rhizobacteria P. simiae WCS417 and Pseudomonas capeferrum WCS358 are highly tolerant of the antimicrobial effect of scopoletin. Collectively, our results demonstrate a role for coumarins in microbiome assembly and point to a scenario in which plants and probiotic rhizobacteria join forces to trigger MYB72/BGLU42-dependent scopolin production and scopoletin excretion, resulting in improved niche establishment for the microbial partner and growth and immunity benefits for the host plant.
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    Low-oxygen response is triggered by an ATP-dependent shift in oleoyl-CoA in Arabidopsis 

    Schmidt, Romy R.; Fulda, Martin; Paul, Melanie V.; Anders, Max; Plum, Frederic; Weits, Daniel A.; Kosmacz, Monika; Larson, Tony R.; Graham, Ian A.; Beemster, Gerrit T. S.; et al.
    Licausi, FrancescoGeigenberger, PeterSchippers, Jos H.van Dongen, Joost T.
    Proceedings of the National Academy of Sciences of the United States of America 2018; 115(51): Art. E12101
    Plant response to environmental stimuli involves integration of multiple signals. Upon low-oxygen stress, plants initiate a set of adaptive responses to circumvent an energy crisis. Here, we reveal how these stress responses are induced by combining (i) energy-dependent changes in the composition of the acyl-CoA pool and (ii) the cellular oxygen concentration. A hypoxia-induced decline of cellular ATP levels reduces LONG-CHAIN ACYL-COA SYNTHETASE activity, which leads to a shift in the composition of the acyl-CoA pool. Subsequently, we show that different acyl-CoAs induce unique molecular responses. Altogether, our data disclose a role for acyl-CoAs acting in a cellular signaling pathway in plants. Upon hypoxia, high oleoyl-CoA levels provide the initial trigger to release the transcription factor RAP2.12 from its interaction partner ACYL-COA BINDING PROTEIN at the plasma membrane. Subsequently, according to the N-end rule for proteasomal degradation, oxygen concentration-dependent stabilization of the subgroup VII ETHYLENE-RESPONSE FACTOR transcription factor RAP2.12 determines the level of hypoxia-specific gene expression. This research unveils a specific mechanism activating low-oxygen stress responses only when a decrease in the oxygen concentration coincides with a drop in energy.
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    The Plasma Membrane: A Platform for Intra- and Intercellular Redox Signaling. 

    Nordzieke, Daniela E.; Medraño-Fernandez, Iria
    Antioxidants 2018; 7(11)
    Membranes are of outmost importance to allow for specific signal transduction due to their ability to localize, amplify, and direct signals. However, due to the double-edged nature of reactive oxygen species (ROS)-toxic at high concentrations but essential signal molecules-subcellular localization of ROS-producing systems to the plasma membrane has been traditionally regarded as a protective strategy to defend cells from unwanted side-effects. Nevertheless, specialized regions, such as lipid rafts and caveolae, house and regulate the activated/inhibited states of important ROS-producing systems and concentrate redox targets, demonstrating that plasma membrane functions may go beyond acting as a securing lipid barrier. This is nicely evinced by nicotinamide adenine dinucleotide phosphate (NADPH)-oxidases (NOX), enzymes whose primary function is to generate ROS and which have been shown to reside in specific lipid compartments. In addition, membrane-inserted bidirectional H₂O₂-transporters modulate their conductance precisely during the passage of the molecules through the lipid bilayer, ensuring time-scaled delivery of the signal. This review aims to summarize current evidence supporting the role of the plasma membrane as an organizing center that serves as a platform for redox signal transmission, particularly NOX-driven, providing specificity at the same time that limits undesirable oxidative damage in case of malfunction. As an example of malfunction, we explore several pathological situations in which an inflammatory component is present, such as inflammatory bowel disease and neurodegenerative disorders, to illustrate how dysregulation of plasma-membrane-localized redox signaling impacts normal cell physiology.
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    Genomic Analysis of the Recent Viral Isolate vB_BthP-Goe4 Reveals Increased Diversity of φ29-Like Phages. 

    Schilling, Tobias; Hoppert, Michael; Hertel, Robert
    Viruses 2018; 10(11): Art. 624
    We present the recently isolated virus vB_BthP-Goe4 infecting Bacillus thuringiensis HD1. Morphological investigation via transmission electron microscopy revealed key characteristics of the genus Phi29virus, but with an elongated head resulting in larger virion particles of approximately 50 nm width and 120 nm height. Genome sequencing and analysis resulted in a linear phage chromosome of approximately 26 kb, harbouring 40 protein-encoding genes and a packaging RNA. Sequence comparison confirmed the relation to the Phi29virus genus and genomes of other related strains. A global average nucleotide identity analysis of all identified φ29-like viruses revealed the formation of several new groups previously not observed. The largest group includes Goe4 and may significantly expand the genus Phi29virus (Salasvirus) or the Picovirinae subfamily.
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    Description of three new species of Aposphragisma Thoma, 2014 (Araneae: Oonopidae) from Sumatra, Indonesia. 

    Fardiansah, Riko; Dupérré, Nadine; Widyastuti, Rahayu; Potapov, Anton; Stefan Scheu; Harms, Danilo
    ZooKeys(797) p.71-85
    Three species from the family Oonopidae are newly described from leaf litter habitats in Sumatra, Indonesia based on male and female morphology. All three species belong to the genus Aposphragisma Thoma, 2014: Aposphragismaglobosumsp. n., Aposphragismajambisp. n., and Aposphragismasumatrasp. n.
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    A barrier island perspective on species–area relationships 

    Scherber, Christoph; Andert, Hagen; Niedringhaus, Rolf; Tscharntke, Teja
    Ecology and Evolution p.1-11
    Predictions of species richness by island area are a classical cornerstone in ecology, while the specific features of barrier islands have been little appreciated. Many shorelines are occupied by barrier islands, which are shaped by offshore sedimentation processes and annual storm tide events. Hence, the appearance of these islands may vary between years if they are not protected by dykes. Here, we analyzed more than 2,990 species across 36 taxonomic groups (including vertebrates, invertebrates, and land plants) on German barrier islands, the East Frisian Islands. We tested for relationships between species richness or species incidence and island area (SAR), island habitat diversity and further island parameters using a range of generalized linear and mixed‐effects models. Overall species richness was explained best by habitat diversity (Shannon index of habitat types). Analyses on the occurrence probability of individual species showed that changes of barrier island area by sedimentation and erosion, that is, barrier island‐specific dynamics, explained the occurrence of 17 of 34 taxa, including most beetles, plants, and birds. Only six taxa such as spiders (249 species) and mammals (27 species) were primarily related to area. The diversity of habitat types was a key predictor for the incidence of twenty‐five taxa, including ground beetles, true bugs and grasshoppers, amphibians, and reptiles. Overall, richness and incidence of taxa differed greatly in their responses, with area (although varying from 0.1 to 38.9 km2) playing a minor and island heterogeneity a major role, while barrier island‐specific sedimentation and erosion turned out to additionally explain species richness and occurrence.
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    Seasonal dynamics and changing sea level as determinants of the community and trophic structure of oribatid mites in a salt marsh of the Wadden Sea 

    Winter, Marlena; Haynert, Kristin; Scheu, Stefan; Maraun, Mark
    PLOS ONE 2018; 13(11): Art. e0207141
    Global change processes affect seasonal dynamics of salt marshes and thereby their plant and animal communities. However, these changes have been little investigated for microarthropod communities. We studied the effect of seasonality and changes in sea level on oribatid mites in the natural salt marsh and on artificial islands in the back-barrier environment of the island Spiekeroog (Wadden Sea, Germany). Three zones of the artificial islands were filled with transplanted sods from the lower salt marsh zone and thereby exposed to three different inundation frequencies. We hypothesized that oribatid mite communities will differ along the natural salt marsh vegetation zones [upper salt marsh (USM), lower salt marsh (LSM), pioneer zone (PZ)], which are influenced by different tidal regimes. Accordingly, total oribatid mite densities declined from the USM and LSM to the PZ. Similarly, oribatid mite species compositions changed along the salt marsh transect and also responded to variations in inundation frequency in LSM on artificial islands with typical species of the USM, LSM and PZ being Multioppia neglecta (USM), Hermannia pulchella (LSM), Zachvatkinibates quadrivertex (LSM, PZ) and Ameronothrus schneideri (LSM, PZ). Oribatid mite density in the salt marsh and on the artificial islands was at a maximum in winter and spring; this was due in part to high density of juveniles, pointing to two reproductive periods. We hypothesized that oribatid mite trophic structure changes due to variations in abiotic (e.g., tidal dynamics, temperature) and biotic conditions (e.g., resource availability). Stable isotope (15N, 13C) and neutral lipid fatty acid analyses indicated that oribatid mite species have different diets with e.g., Z. quadrivertex feeding on macroalgae and fungi, A. schneideri feeding on microalgae and bacteria, and Scheloribates laevigatus and M. neglecta feeding on dead organic matter, bacteria and fungi. Overall, the results indicate that oribatid mite species in salt marshes are affected by changes in environmental factors such as inundation intensity, with the effects being most pronounced in species with narrow trophic niches and limited niche plasticity. The results also indicate that oribatid mite communities of the LSM respond little to short-term (one year) changes in inundation frequency.
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    Money or smiles: Independent ERP effects of associated monetary reward and happy faces 

    Hammerschmidt, Wiebke; Kulke, Louisa; Broering, Christina; Schacht, Annekathrin
    PLOS ONE 2018; 13(10): Art. e0206142
    n comparison to neutral faces, facial expressions of emotion are known to gain attentional prioritization, mainly demonstrated by means of event-related potentials (ERPs). Recent evidence indicated that such a preferential processing can also be elicited by neutral faces when associated with increased motivational salience via reward. It remains, however, an open question whether impacts of inherent emotional salience and associated motivational salience might be integrated. To this aim, expressions and monetary outcomes were orthogonally combined. Participants (N = 42) learned to explicitly categorize happy and neutral faces as either reward- or zero-outcome-related via an associative learning paradigm. ERP components (P1, N170, EPN, and LPC) were measured throughout the experiment, and separately analyzed before (learning phase) and after (consolidation phase) reaching a pre-defined learning criterion. Happy facial expressions boosted early processing stages, as reflected in enhanced amplitudes of the N170 and EPN, both during learning and consolidation. In contrast, effects of monetary reward became evident only after successful learning and in form of enlarged amplitudes of the LPC, a component linked to higher-order evaluations. Interactions between expressions and associated outcome were absent in all ERP components of interest. The present study provides novel evidence that acquired salience impacts stimulus processing but independent of the effects driven by happy facial expressions.
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    Bacterial infections among patients with psychiatric disorders: Relation with hospital stay, age, and psychiatric diagnoses 

    Belz, Michael; Rehling, Nico; Schmidt, Ulrike; Wiltfang, Jens; Kis, Bernhard; Wolff-Menzler, Claus
    PLOS ONE 2018; 13(12): Art. e0208458
    The prevalence of infections is supposed to be higher in older patients and to extend the length of hospital stays. This study aimed, first, to test this supposition within a large psychiatric population which we divided into four clusters of psychiatric ICD-10 diagnoses: F00-F03 (dementias), F10 (substance disorders), F20-29 (schizophrenia, schizophreniform and other non-mood psychotic disorders), F32-F33 (major depressive disorders). Second, despite the increasing evidence for the role of infections in psychiatric disorders, it is, to the best of our knowledge, largely unknown whether the rates of infections with pathogens of the four most frequent germ families differ between psychiatric diseases. Thus, in a retrospective study, the results of clinical routine examinations (pap smear, analysis of midstream urine, stool) dependent on symptoms in 8545 patients of a German psychiatric clinic were analyzed in a 12-year dataset. Results show that a longer hospital stay was associated with an increased number of microbiological tests, but led to no significant difference between positive vs. negative findings. Consistent with previous studies, patients with infections were older than patients without infections. For the F10 diagnosis cluster we found a significantly reduced (F10: Staphylococcaceae) and for the F20-29 cluster a heightened risk of infections (Staphylococcaceae, Corynebacteriaceae). Furthermore, patients belonging to the F00-F03 cluster exhibited elevated rates of infections with all four germ families. The latter can be ascribed to patients' age as we found higher age to be associated with these infections, independently of the presence of dementia. Our results suggest that different psychiatric diagnoses are associated with a heightened or lowered risk of bacterial infections and, furthermore, that clinical routine infection-screenings for elderly psychiatric patients seems to be reasonable.
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    Response of Collembola and Acari communities to summer flooding in a grassland plant diversity experiment 

    González-Macé, Odette; Scheu, Stefan
    PLOS ONE 2018; 13(8): Art. e0202862
    Flooding frequency is predicted to increase during the next decades in Europe. Therefore, it is important to understand how short-term disturbance events affect soil biota providing essential ecosystem functions and uncover factors modulating their response such as plant community composition. Here we report on the response of soil microarthropod communities (Collembola and Acari) to a severe summer flood in 2013, which affected major parts of central Europe. Collembola and Acari density and Collembola and Oribatida richness were strongly affected by the flood, but they recovered within three months. Effects of plant community composition on soil microarthropods disappeared after the flood, presumably due to homogenization of the field, but the effects of plant community were in a stage of being reasserted three months after the flood. Widespread, surface living and generalistic microarthropod species recolonized the field quickly. Prostigmata and Oribatida were more resilient or recovered to flooding than Astigmata and Gamasida. Long-term impacts, however, remain unknown and deserve further investigation.
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    Using imaging photoplethysmography for heart rate estimation in non-human primates 

    Unakafov, Anton M.; Möller, Sebastian; Kagan, Igor; Gail, Alexander; Treue, Stefan; Wolf, Fred
    PLOS ONE 2018; 13(8): Art. e0202581
    For humans and for non-human primates heart rate is a reliable indicator of an individual's current physiological state, with applications ranging from health checks to experimental studies of cognitive and emotional state. In humans, changes in the optical properties of the skin tissue correlated with cardiac cycles (imaging photoplethysmogram, iPPG) allow noncontact estimation of heart rate by its proxy, pulse rate. Yet, there is no established simple and non-invasive technique for pulse rate measurements in awake and behaving animals. Using iPPG, we here demonstrate that pulse rate in rhesus monkeys can be accurately estimated from facial videos. We computed iPPGs from eight color facial videos of four awake head-stabilized rhesus monkeys. Pulse rate estimated from iPPGs was in good agreement with reference data from a contact pulse-oximeter: the error of pulse rate estimation was below 5% of the individual average pulse rate in 83% of the epochs; the error was below 10% for 98% of the epochs. We conclude that iPPG allows non-invasive and non-contact estimation of pulse rate in non-human primates, which is useful for physiological studies and can be used toward welfare-assessment of non-human primates in research.
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    Functional diversity changes over 100 yr of primary succession on a volcanic island: insights into assembly processes 

    Karadimou, E.; Kallimanis, A. S.; Tsiripidis, I.; Raus, T.; Bergmeier, E.; Dimopoulos, P.
    Ecosphere 2018; 9(9): Art. e02374
    Changes in species diversity following volcanic eruptions have been studied extensively, but our knowledge on functional diversity and community assembly under such conditions is very limited. Here, we study the processes following the destruction of vegetation after a volcanic eruption. Specifically, we investigate (1) the temporal patterns of taxonomic and functional diversity over time since a previous eruption (alpha diversity) and beta diversity, (2) the temporal patterns of 26 individual traits (vegetative characteristics, plant taxa ecological preferences, and regenerative characteristics) providing more detailed information on species strategies at the initial and later stages of succession, and (3) the processes driving species assembly and whether they changed over time since the eruption an eruption. We analyzed data recorded during five floristic censuses that took place between 1911 and 2011, calculated alpha and beta facets of taxonomic and functional diversity and examined how community structure changed over time, using 26 functional characteristics, based on their ability to discern primary from later colonists, including longevity, growth form, Ellenberg’s indicator values, seed production and weight, flower size and sex, pollination type, and dispersal mode. Null model analysis was used to test whether the observed functional diversity deviates from random expectations. Alpha diversity, both taxonomic and functional, increased over time after an eruption, while beta diversity did not display a clear trend. This finding indicates that mainly abiotic processes determine species assembly over time after an eruption (at least for the time span studied here), contrary to theoretical expectations. It is most interesting that, simultaneously, some aspects of diversity indicated the effect of biotic interactions (facilitation and competition) on the assembly of species a few years after an eruption. This finding implies a legacy effect, since a high percentage of perennial species was noticed in the assemblage right after the eruption, as well as the effect of the harsh environmental conditions on the assembly of the plant communities. In conclusion, our results indicate the role of legacy effects in succession (most probably through the survival of underground plant parts) and underline the importance of disturbance history in providing the context needed for understanding effects of past events on succession.
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    How Rainforest Conversion to Agricultural Systems in Sumatra (Indonesia) Affects Active Soil Bacterial Communities 

    Berkelmann, Dirk; Schneider, Dominik; Engelhaupt, Martin; Heinemann, Melanie; Christel, Stephan; Wijayanti, Marini; Meryandini, Anja; Daniel, Rolf
    Frontiers in Microbiology 2018; 9: Art. 2381
    Palm oil production in Indonesia increased constantly over the last decades, which led to massive deforestation, especially on Sumatra island. The ongoing conversion of rainforest to agricultural systems results in high biodiversity loss. Here, we present the first RNA-based study on the effects of rainforest transformation to rubber and oil palm plantations in Indonesia for the active soil bacterial communities. For this purpose, bacterial communities of three different converted systems (jungle rubber, rubber plantation, and oil palm plantation) were studied in two landscapes with rainforest as reference by RT-PCR amplicon-based analysis of 16S rRNA gene transcripts. Active soil bacterial communities were dominated by Frankiales (Actinobacteria), subgroup 2 of the Acidobacteria and Alphaproteobacteria (mainly Rhizobiales and Rhodospirillales). Community composition differed significantly between the converted land use systems and rainforest reference sites. Alphaproteobacteria decreased significantly in oil palm samples compared to rainforest samples. In contrast, relative abundances of taxa within the Acidobacteria increased. Most important abiotic drivers for shaping soil bacterial communities were pH, calcium concentration, base saturation and C:N ratio. Indicator species analysis showed distinct association patterns for the analyzed land use systems. Nitrogen-fixing taxa including members of Rhizobiales and Rhodospirillales were associated with rainforest soils while nitrifiers and heat-resistant taxa including members of Actinobacteria were associated with oil palm soils. Predicted metabolic profiles revealed that the relative abundances of genes associated with fixation of nitrogen significantly decreased in plantation soils. Furthermore, predicted gene abundances regarding motility, competition or gene transfer ability indicated rainforest conversion-induced changes as well.
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    A perforated anodised aluminium slide for improved specimen clearing and imaging for confocal laser scanning microscopy 

    Quade, Felix S. C.; Preitz, Beate; Prpic, Nikola-Michael
    2018; 11(1): Art. 716
    Objective The bleaching, clearing and handling of tiny specimens with soft tissue and cuticular components for confocal laser scanning microscopy is difficult, because after cuticle bleaching and tissue clearing the specimens are virtually invisible. We have adjusted the design of the specimen container described by Smolla et al. (Arthropod Struct Dev 43:175–81, 2014) to handle tiny specimens. Results We describe a perforated and anodised aluminium slide that was designed to hold the distal tips of the pedipalp appendages of the spider Parasteatoda tepidariorum during clearing, and that can then be used directly for confocal laser scanning microscopy. We believe that this slide design will be helpful for others who want to visualise specimens between 500 and 800 µm with confocal laser scanning microscopy.
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    Developmental studies provide new insights into the evolution of sense organs in Sabellariidae (Annelida) 

    Helm, Conrad; Bok, Michael J; Hutchings, Pat; Kupriyanova, Elena; Capa, María
    2018; 18(1): Art. 149
    Abstract Background Sabellarids, also known as honeycomb or sandcastle worms, when building their tubes, produce chemical signals (free fatty acids) that are responsible for larval settlement and the formation of three-dimensional aggregations. The larval palps and the dorsal hump (becoming the median organ in adults) are presumed to participate in such a substrate selection during settlement. Notably, the sabellariid median organ is an apparently unique organ among annelids that has been attributed with a sensory function and perhaps with some affinities to the nuchal organs of other polychaetes. Nevertheless, detailed investigations of this prominent character complex including ultrastructural examinations are lacking so far. Results Our comprehensive investigations provide data about the anterior sensory organs in Sabellariidae and inform about their transformation during pelagic larval development. We used a comparative approach including immunostaining with subsequent confocal laser scanning microscopy (clsm), histological sections as well as electron microscopy in a range of larval and adult stages of two sabellariid species. We find that the neuronal innervation as well as the ultrastructure of the sabellariid ciliary structures along the median organ are highly comparable with that of nuchal organs known from other polychaetes. Furthermore, the myoinhibitory protein (MIP) – a protein known to be also involved into chemo-sensation - was detected in the region of the larval median organ. Moreover, we reveal the presence of an unusual type of photoreceptor as part of the median organ in Idanthyrsus australiensis with a corrugated sensory membrane ultrastructure unlike those observed in the segmental ocelli of other polychaetes. Conclusions We are describing for the first time the nuchal organ-like structures in different developmental stages of two species of Sabellariidae. The external morphology, neuronal innervation, developmental fate and ultrastructure of the newly-discovered median organ-based ciliary pits are comparable with the characteristics known for annelid nuchal organs and therefore indicate a homology of both sensory complexes. The presence of myoinhibitory peptide (MIP) in the respective region supports such a hypothesis and exhibits the possibility of an involvement of the entire sabellariid median organ complex, and in particular the prominent ciliated pits, in chemo-sensation.
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    RAD sequencing resolved phylogenetic relationships in European shrub willows (Salix L. subg. Chamaetia and subg. Vetrix) and revealed multiple evolution of dwarf shrubs 

    Wagner, Natascha Dorothea; Gramlich, Susanne; Hörandl, Elvira
    Ecology and Evolution 2018; 8(16) p.8243-8255
    The large and diverse genus Salix L. is of particular interest for decades of biological research. However, despite the morphological plasticity, the reconstruction of phylogenetic relationships was so far hampered by the lack of informative molecular markers. Infrageneric classification based on morphology separates dwarf shrubs (subg. Chamaetia) and taller shrubs (subg. Vetrix), while previous phylogenetic studies placed species of these two subgenera just in one largely unresolved clade. Here we want to test the utility of genomic RAD sequencing markers for resolving relationships at different levels of divergence in Salix. Based on a sampling of 15 European species representing 13 sections of the two subgenera, we used five different RAD sequencing datasets generated by ipyrad to conduct phylogenetic analyses. Additionally we reconstructed the evolution of growth form and analyzed the genetic composition of the whole clade. The results showed fully resolved trees in both ML and BI analysis with high statistical support. The two subgenera Chamaetia and Vetrix were recognized as nonmonophyletic, which suggests that they should be merged. Within the Vetrix/Chamaetia clade, a division into three major subclades could be observed. All species were confirmed to be monophyletic. Based on our data, arctic-alpine dwarf shrubs evolved four times independently. The structure analysis showed five mainly uniform genetic clusters which are congruent in sister relationships observed in the phylogenies. Our study confirmed RAD sequencing as a useful genomic tool for the reconstruction of relationships on different taxonomic levels in the genus Salix.
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    Cattle selectivity by leopards suggests ways to mitigate human-leopard conflict 

    Khorozyan, Igor; Ghoddousi, Siavash; Soufi, Mobin; Soofi, Mahmood; Waltert, Matthias
    Ecology and Evolution 2018; 8(16) p.8011-8018
    Addressing widespread livestock losses to carnivores requires information on which livestock categories are preferentially selected. We analyzed an individual-based database of cattle grazing in forest (n = 932) and having been killed (n = 70) by leopards (Panthera pardus) in the Hyrcanian forest, Iran. We calculated Jacobs' selectivity index for cattle age, sex, and coloration across four scales: the study area as a whole, three sites, nine villages, and 60 cattle owners. Naturally colored cattle were significantly preferred by leopards at all scales in comparison with black and black-and-white cattle, and there was also a preference for males and juveniles at the study area level. More research is needed to see whether cattle losses would decrease if the share of naturally colored individuals in local holdings was reduced and males and juveniles had limited access to forest. We conclude that phenotypic and biologic characteristics of livestock can affect depredation and appeal for more research in this direction, particularly within the predator-prey framework.
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    Testing the plant pneumatic method to estimate xylem embolism resistance in stems of temperate trees 

    Zhang, Ya; Lamarque, Laurent J.; Torres-Ruiz, José M.; Schuldt, Bernhard; Karimi, Zohreh; Li, Shan; Qin, De-Wen; Bittencourt, Paulo; Burlett, Régis; Cao, Kun-Fang; et al.
    Delzon, SylvainOliveira, RafaelPereira, LucianoJansen, Steven
    Tree Physiology 2018; 38(7) p.1016-1025
    Methods to estimate xylem embolism resistance generally rely on hydraulic measurements, which can be far from straightforward. Recently, a pneumatic method based on air flow measurements of terminal branch ends was proposed to construct vulnerability curves by linking the amount of air extracted from a branch with the degree of embolism. We applied this novel technique for 10 temperate tree species, including six diffuse, two ring-porous and two gymnosperm species, and compared the pneumatic curves with hydraulic ones obtained from either the flow-centrifuge or the hydraulic-bench dehydration method. We found that the pneumatic method provides a good estimate of the degree of xylem embolism for all angiosperm species. The xylem pressure at 50% and 88% loss of hydraulic conductivity (i.e., Ψ50 and Ψ88) based on the methods applied showed a strongly significant correlation for all eight angiosperms. However, the pneumatic method showed significantly reduced Ψ50 values for the two conifers. Our findings suggest that the pneumatic method could provide a fast and accurate approach for angiosperms due to its convenience and feasibility, at least within the range of embolism resistances covered by our samples.
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    Velvet domain protein VosA represses the zinc cluster transcription factor SclB regulatory network for Aspergillus nidulans asexual development, oxidative stress response and secondary metabolism. 

    Thieme, Karl G.; Gerke, Jennifer; Sasse, Christoph; Valerius, Oliver; Thieme, Sabine; Karimi, Razieh; Heinrich, Antje K.; Finkernagel, Florian; Smith, Kristina; Bode, Helge B.; et al.
    Freitag, MichaelRam, Arthur F. J.Braus, Gerhard H.
    PLOS Genetics 2018; 14(7): Art. e1007511
    The NF-κB-like velvet domain protein VosA (viability of spores) binds to more than 1,500 promoter sequences in the filamentous fungus Aspergillus nidulans. VosA inhibits premature induction of the developmental activator gene brlA, which promotes asexual spore formation in response to environmental cues as light. VosA represses a novel genetic network controlled by the sclB gene. SclB function is antagonistic to VosA, because it induces the expression of early activator genes of asexual differentiation as flbC and flbD as well as brlA. The SclB controlled network promotes asexual development and spore viability, but is independent of the fungal light control. SclB interactions with the RcoA transcriptional repressor subunit suggest additional inhibitory functions on transcription. SclB links asexual spore formation to the synthesis of secondary metabolites including emericellamides, austinol as well as dehydroaustinol and activates the oxidative stress response of the fungus. The fungal VosA-SclB regulatory system of transcription includes a VosA control of the sclB promoter, common and opposite VosA and SclB control functions of fungal development and several additional regulatory genes. The relationship between VosA and SclB illustrates the presence of a convoluted surveillance apparatus of transcriptional control, which is required for accurate fungal development and the linkage to the appropriate secondary metabolism.
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