TY - JOUR A1 - Kuhl, Heiner A1 - Guiguen, Yann A1 - Höhne, Christin A1 - Kreuz, Eva A1 - Du, Kang A1 - Klopp, Christophe A1 - Lopez-Roques,, Céline A1 - Yebra-Pimentel, Elena Santidrian A1 - Ciorpac, Mitica A1 - Gessner, Jörn A1 - Holostenco, Daniela A1 - Kleiner, Wibke A1 - Kohlmann, Klaus A1 - Lamatsch, Dunja K. A1 - Prokopov, Dmitry A1 - Bestin, Anastasia A1 - Bonpunt, Emmanuel A1 - Debeuf, Bastien A1 - Haffray, Pierrick A1 - Morvezen, Romain A1 - Patrice, Pierre A1 - Suciu, Radu A1 - Dirks, Ron A1 - Wuertz, Sven A1 - Kloas, Werner A1 - Schartl, Manfred A1 - Stöck, Matthias T1 - A 180 Myr-old female-specific genome region in sturgeon reveals the oldest known vertebrate sex determining system with undifferentiated sex chromosomes JF - Philosophical Transactions of the Royal Society B N2 - Several hypotheses explain the prevalence of undifferentiated sex chromosomes in poikilothermic vertebrates. Turnovers change the master sex determination gene, the sex chromosome or the sex determination system (e.g. XY to WZ). Jumping master genes stay main triggers but translocate to other chromosomes. Occasional recombination (e.g. in sex-reversed females) prevents sex chromosome degeneration. Recent research has uncovered conserved heteromorphic or even homomorphic sex chromosomes in several clades of non-avian and non-mammalian vertebrates. Sex determination in sturgeons (Acipenseridae) has been a long-standing basic biological question, linked to economical demands by the caviar-producing aquaculture. Here, we report the discovery of a sex-specific sequence from sterlet (Acipenser ruthenus). Using chromosome-scale assemblies and pool-sequencing, we first identified an approximately 16 kb female-specific region. We developed a PCR-genotyping test, yielding female-specific products in six species, spanning the entire phylogeny with the most divergent extant lineages (A. sturio, A. oxyrinchus versus A. ruthenus, Huso huso), stemming from an ancient tetraploidization. Similar results were obtained in two octoploid species (A. gueldenstaedtii, A. baerii). Conservation of a female-specific sequence for a long period, representing 180 Myr of sturgeon evolution, and across at least one polyploidization event, raises many interesting biological questions. We discuss a conserved undifferentiated sex chromosome system with a ZZ/ZW-mode of sex determination and potential alternatives. This article is part of the theme issue ‘Challenging the paradigm in sex chromosome evolution: empirical and theoretical insights with a focus on vertebrates (Part I)’. KW - acipenseridae KW - sturgeon KW - sex chromosomes KW - female-specific KW - polyploidy KW - evolution Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-363050 VL - 376 ER - TY - JOUR A1 - Graus, Dorothea A1 - Konrad, Kai R. A1 - Bemm, Felix A1 - Nebioglu, Meliha Görkem Patir A1 - Lorey, Christian A1 - Duscha, Kerstin A1 - Güthoff, Tilman A1 - Herrmann, Johannes A1 - Ferjani, Ali A1 - Cuin, Tracey Ann A1 - Roelfsema, M. Rob G. A1 - Schumacher, Karin A1 - Neuhaus, H. Ekkehard A1 - Marten, Irene A1 - Hedrich, Rainer T1 - High V-PPase activity is beneficial under high salt loads, but detrimental without salinity JF - New Phytologist N2 - The membrane-bound proton-pumping pyrophosphatase (V-PPase), together with the V-type H+-ATPase, generates the proton motive force that drives vacuolar membrane solute transport. Transgenic plants constitutively overexpressing V-PPases were shown to have improved salinity tolerance, but the relative impact of increasing PPi hydrolysis and proton-pumping functions has yet to be dissected. For a better understanding of the molecular processes underlying V-PPase-dependent salt tolerance, we transiently overexpressed the pyrophosphate-driven proton pump (NbVHP) in Nicotiana benthamiana leaves and studied its functional properties in relation to salt treatment by primarily using patch-clamp, impalement electrodes and pH imaging. NbVHP overexpression led to higher vacuolar proton currents and vacuolar acidification. After 3 d in salt-untreated conditions, V-PPase-overexpressing leaves showed a drop in photosynthetic capacity, plasma membrane depolarization and eventual leaf necrosis. Salt, however, rescued NbVHP-hyperactive cells from cell death. Furthermore, a salt-induced rise in V-PPase but not of V-ATPase pump currents was detected in nontransformed plants. The results indicate that under normal growth conditions, plants need to regulate the V-PPase pump activity to avoid hyperactivity and its negative feedback on cell viability. Nonetheless, V-PPase proton pump function becomes increasingly important under salt stress for generating the pH gradient necessary for vacuolar proton-coupled Na+ sequestration. KW - cell death KW - plasma membrane voltage KW - proton pump currents KW - salt KW - vacuolar pH KW - vacuolar proton-ATPase (V-ATPase) KW - vacuolar proton-pyrophosphatase (V-PPase) Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-227553 VL - 219 ER - TY - JOUR A1 - Chevalier‐Roignant, Benoît A1 - Flath, Christoph M. A1 - Trigeorgis, Lenos T1 - Disruptive Innovation, Market Entry and Production Flexibility in Heterogeneous Oligopoly JF - Production and Operations Management N2 - We develop a model of oligopoly competition involving innovation effort, market entry and production flexibility under demand uncertainty. Several heterogeneous firms make efforts to develop new prototypes; if they succeed, they hold a shared option to enter a new market under stochastic demand. We derive analytic results for the Markov perfect equilibrium accounting for development effort, market entry and production decisions and complement these by numerical analyses. Firm value—which embeds real options—is not convex increasing in demand but exhibits “competitive waves” due to market entries by rivals. A firm with a development advantage (“innovator”) exerts greater innovation effort if the market is a niche, whereas another benefiting from economies of scale (“incumbent”) invests more if the market is larger. Positive externalities benefit the incumbent in the development stage, whereas the innovator is better off in counteracting negative externalities. Demand volatility raises firm incentives to innovate as it enhances the value of firm market‐entry and production flexibility. KW - disruptive innovation KW - market entry KW - production flexibility KW - oligopoly Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-356226 VL - 28 ER - TY - JOUR A1 - Andreatta, Marta A1 - Pauli, Paul T1 - Generalization of appetitive conditioned responses JF - Psychophysiology N2 - A stimulus (conditioned stimulus, CS) associated with an appetitive unconditioned stimulus (US) acquires positive properties and elicits appetitive conditioned responses (CR). Such associative learning has been examined extensively in animals with food as the US, and results are used to explain psychopathologies (e.g., substance-related disorders or obesity). Human studies on appetitive conditioning exist, too, but we still know little about generalization processes. Understanding these processes may explain why stimuli not associated with a drug, for instance, can elicit craving. Forty-seven hungry participants underwent an appetitive conditioning protocol during which one of two circles with different diameters (CS+) became associated with an appetitive US (chocolate or salty pretzel, according to participants’ preference) but never the other circle (CS−). During generalization, US were delivered twice and the two CS were presented again plus four circles (generalization stimuli, GS) with gradually increasing diameters from CS− to CS+. We found successful appetitive conditioning as reflected in appetitive subjective ratings (positive valence, higher contingency) and physiological responses (startle attenuation and larger skin conductance responses) to CS+ versus CS−, and, importantly, both measures confirmed generalization as indicated by generalization gradients. Small changes in CS-US contingency during generalization may have weakened generalization processes on the physiological level. Considering that appetitive conditioned responses can be generalized to non-US-associated stimuli, a next important step would be to investigate risk factors that mediate overgeneralization. KW - appetitive conditioning; ; KW - generalization KW - primary reinforcer KW - startle reflex Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-221132 VL - 56 ER - TY - JOUR A1 - Lehmann, Julian A1 - Jørgensen, Morten E. A1 - Fratz, Stefanie A1 - Müller, Heike M. A1 - Kusch, Jana A1 - Scherzer, Sönke A1 - Navarro-Retamal, Carlos A1 - Mayer, Dominik A1 - Böhm, Jennifer A1 - Konrad, Kai R. A1 - Terpitz, Ulrich A1 - Dreyer, Ingo A1 - Mueller, Thomas D. A1 - Sauer, Markus A1 - Hedrich, Rainer A1 - Geiger, Dietmar A1 - Maierhofer, Tobias T1 - Acidosis-induced activation of anion channel SLAH3 in the flooding-related stress response of Arabidopsis JF - Current Biology N2 - Plants, as sessile organisms, gained the ability to sense and respond to biotic and abiotic stressors to survive severe changes in their environments. The change in our climate comes with extreme dry periods but also episodes of flooding. The latter stress condition causes anaerobiosis-triggered cytosolic acidosis and impairs plant function. The molecular mechanism that enables plant cells to sense acidity and convey this signal via membrane depolarization was previously unknown. Here, we show that acidosis-induced anion efflux from Arabidopsis (Arabidopsis thaliana) roots is dependent on the S-type anion channel AtSLAH3. Heterologous expression of SLAH3 in Xenopus oocytes revealed that the anion channel is directly activated by a small, physiological drop in cytosolic pH. Acidosis-triggered activation of SLAH3 is mediated by protonation of histidine 330 and 454. Super-resolution microscopy analysis showed that the increase in cellular proton concentration switches SLAH3 from an electrically silent channel dimer into its active monomeric form. Our results show that, upon acidification, protons directly switch SLAH3 to its open configuration, bypassing kinase-dependent activation. Moreover, under flooding conditions, the stress response of Arabidopsis wild-type (WT) plants was significantly higher compared to SLAH3 loss-of-function mutants. Our genetic evidence of SLAH3 pH sensor function may guide the development of crop varieties with improved stress tolerance. KW - SLAH3 KW - S-type anion channel KW - hypoxia KW - pH KW - cytosolic acidification KW - flooding KW - PALM KW - stoichiometry Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-363320 VL - 31 ER - TY - JOUR A1 - Jotz Lean, Madeleine A1 - Mackenzie, Kirill C. H. T1 - Transitive double Lie algebroids via core diagrams JF - Journal of Geometric Mechanics N2 - The core diagram of a double Lie algebroid consists of the core of the double Lie algebroid, together with the two core-anchor maps to the sides of the double Lie algebroid. If these two core-anchors are surjective, then the double Lie algebroid and its core diagram are called transitive. This paper establishes an equivalence between transitive double Lie algebroids, and transitive core diagrams over a fixed base manifold. In other words, it proves that a transitive double Lie algebroid is completely determined by its core diagram. The comma double Lie algebroid associated to a morphism of Lie algebroids is defined. If the latter morphism is one of the core-anchors of a transitive core diagram, then the comma double algebroid can be quotiented out by the second core-anchor, yielding a transitive double Lie algebroid, which is the one that is equivalent to the transitive core diagram. Brown's and Mackenzie's equivalence of transitive core diagrams (of Lie groupoids) with transitive double Lie groupoids is then used in order to show that a transitive double Lie algebroid with integrable sides and core is automatically integrable to a transitive double Lie groupoid. KW - double Lie algebroids KW - double Lie groupoids KW - comma category KW - representations up to homotopy KW - matched pairs KW - Lie bialgebroids KW - infinitesimal ideal systems KW - integration Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-363224 VL - 13 ER - TY - JOUR A1 - Le Provost, Gaëtane A1 - Thiele, Jan A1 - Westphal, Catrin A1 - Penone, Caterina A1 - Allan, Eric A1 - Neyret, Margot A1 - van der Plas, Fons A1 - Ayasse, Manfred A1 - Bardgett, Richard D. A1 - Birkhofer, Klaus A1 - Boch, Steffen A1 - Bonkowski, Michael A1 - Buscot, Francois A1 - Feldhaar, Heike A1 - Gaulton, Rachel A1 - Goldmann, Kezia A1 - Gossner, Martin M. A1 - Klaus, Valentin H. A1 - Kleinebecker, Till A1 - Krauss, Jochen A1 - Renner, Swen A1 - Scherreiks, Pascal A1 - Sikorski, Johannes A1 - Baulechner, Dennis A1 - Blüthgen, Nico A1 - Bolliger, Ralph A1 - Börschig, Carmen A1 - Busch, Verena A1 - Chisté, Melanie A1 - Fiore-Donno, Anna Maria A1 - Fischer, Markus A1 - Arndt, Hartmut A1 - Hoelzel, Norbert A1 - John, Katharina A1 - Jung, Kirsten A1 - Lange, Markus A1 - Marzini, Carlo A1 - Overmann, Jörg A1 - Paŝalić, Esther A1 - Perović, David J. A1 - Prati, Daniel A1 - Schäfer, Deborah A1 - Schöning, Ingo A1 - Schrumpf, Marion A1 - Sonnemann, Ilja A1 - Steffan-Dewenter, Ingolf A1 - Tschapka, Marco A1 - Türke, Manfred A1 - Vogt, Juliane A1 - Wehner, Katja A1 - Weiner, Christiane A1 - Weisser, Wolfgang A1 - Wells, Konstans A1 - Werner, Michael A1 - Wolters, Volkmar A1 - Wubet, Tesfaye A1 - Wurst, Susanne A1 - Zaitsev, Andrey S. A1 - Manning, Peter T1 - Contrasting responses of above- and belowground diversity to multiple components of land-use intensity JF - Nature Communications N2 - Land-use intensification is a major driver of biodiversity loss. However, understanding how different components of land use drive biodiversity loss requires the investigation of multiple trophic levels across spatial scales. Using data from 150 agricultural grasslands in central Europe, we assess the influence of multiple components of local- and landscape-level land use on more than 4,000 above- and belowground taxa, spanning 20 trophic groups. Plot-level land-use intensity is strongly and negatively associated with aboveground trophic groups, but positively or not associated with belowground trophic groups. Meanwhile, both above- and belowground trophic groups respond to landscape-level land use, but to different drivers: aboveground diversity of grasslands is promoted by diverse surrounding land-cover, while belowground diversity is positively related to a high permanent forest cover in the surrounding landscape. These results highlight a role of landscape-level land use in shaping belowground communities, and suggest that revised agroecosystem management strategies are needed to conserve whole-ecosystem biodiversity. KW - biodiversity KW - community ecology KW - grassland ecology Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-371552 VL - 12 ER - TY - JOUR A1 - Landing, Ed A1 - Geyer, Gerd A1 - Schmitz, Mark D. A1 - Wotte, Thomas A1 - Kouchinsky, Artem T1 - (Re)proposal of three Cambrian Subsystems and their Geochronology JF - Episodes N2 - The Cambrian is anomalous among geological systems as many reports divide it into three divisions of indeterminate rank. This use of “lower”, “middle”, and “upper” has been a convenient way to subdivide the Cambrian despite agreement it consists of four global series. Traditional divisions of the system into regional series (Lower, Middle, Upper) reflected local biotic developments not interprovincially correlatable with any precision. However, use of “lower”, “middle”, and “upper” is unsatisfactory. These adjectives lack standard definition, evoke the regional series, and are misused. Notably, there is an almost 50 year use of three Cambrian subsystems and a 1997 proposal to divide the Avalonian and global Cambrian into four series and three subsystems. The global series allow proposal of three formal subsystems: a ca. 32.6 Ma Lower Cambrian Subsystem (Terreneuvian and Series 2/proposed Lenaldanian Series), a ca. 9.8 Ma Middle, and a ca. 10 Ma Upper Cambrian Subsystem (=Furongian Series). Designations as “Lower Cambrian Subsystem” or “global Lower Cambrian” distinguish the new units from such earlier units as “Lower Cambrian Series” and substitute for the de facto subsystem terms “lower”, “middle”, and “upper”. Cambrian subsystems are comparable to the Carboniferous’ Lower (Mississippian) and Upper (Pennsylvanian) Subsystems. Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-363144 VL - 44 ER - TY - JOUR A1 - Larrieu, Laurent A1 - Cabanettes, Alain A1 - Courbaud, Benoit A1 - Goulard, Michel A1 - Heintz, Wilfried A1 - Kozák, Daniel A1 - Kraus, Daniel A1 - Lachat, Thibault A1 - Ladet, Sylvie A1 - Müller, Jörg A1 - Paillet, Yoan A1 - Schuck, Andreas A1 - Stillhard, Jonas A1 - Svoboda, Miroslav T1 - Co-occurrence patterns of tree-related microhabitats: A method to simplify routine monitoring JF - Ecological Indicators N2 - A Tree-related Microhabitat (TreM) is a distinct, well-delineated morphological singularity occurring on living or standing dead trees, which constitutes a crucial substrate or life site for various species. TreMs are widely recognized as key features for biodiversity. Current TreM typology identifies 47 TreM types according to their morphology and their associated taxa. In order to provide a range of resolutions and make the typology more user-friendly, these 47 TreM types have been pooled into 15 groups and seven forms. Depending on the accuracy required and the time available, a user can now choose to describe TreMs at resolution levels corresponding to type, group or form. Another way to more easily record TreMs during routine management work would be to use co-occurrence patterns to reduce the number of observed TreMs required. Based on a large international TreM database (2052 plots; 70,958 individual trees; 78 tree species), we evaluated both the significance and the magnitude of TreM co-occurrence on living trees for 11 TreM groups. We highlighted 33 significant co-occurrences for broadleaves and nine for conifers. Bark loss, rot hole, crack and polypore had the highest number of positive co-occurrences (N = 8) with other TreMs on broadleaves; bark loss (N = 4) had the highest number for conifers. We found mutually exclusive occurrences only for conifers: Exposed Heartwood excluded both dendrotelm and sap run. Among the four variables we tested for their positive contribution to significant co-occurrences, tree diameter at breast height was the most consistent. Based on our results and practical considerations, we selected three TreM groups for broadleaves, and nine for conifers, and formed useful short lists to reduce the number of TreM groups to assess during routine forest management work in the field. In addition, detecting potential similarities or associations between TreMs has potential theoretical value, e.g. it may help researchers identify common factors favouring TreM formation or help managers select trees with multiple TreMs as candidates for retention. KW - TreM monitoring KW - biodiversity-friendly forest management Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-363158 VL - 127 ER - TY - JOUR A1 - Banas, Bernhard A1 - Steubl, Dominik A1 - Renders, Lutz A1 - Chittka, Dominik A1 - Banas, Miriam C. A1 - Wekerle, Thomas A1 - Koch, Martina A1 - Witzke, Oliver A1 - Mühlfeld, Anja A1 - Sommerer, Claudia A1 - Habicht, Antje A1 - Hugo, Christian A1 - Hünig, Thomas A1 - Lindemann, Monika A1 - Schmidt, Traudel A1 - Rascle, Anne A1 - Barabas, Sascha A1 - Deml, Ludwig A1 - Wagner, Ralf A1 - Krämer, Bernhard K. A1 - Krüger, Bernd T1 - Clinical validation of a novel enzyme-linked immunosorbent spot assay-based in vitro diagnostic assay to monitor cytomegalovirus-specific cell-mediated immunity in kidney transplant recipients: a multicenter, longitudinal, prospective, observational study JF - Transplant International N2 - Impaired cytomegalovirus (CMV)-specific cell-mediated immunity (CMV-CMI) is a major cause of CMV reactivation and associated complications in solid-organ transplantation. Reliably assessing CMV-CMI is desirable to individually adjust antiviral and immunosuppressive therapy. This study aimed to evaluate the suitability of T-Track® CMV, a novel IFN-γ ELISpot assay based on the stimulation of peripheral blood mononuclear cells with pp65 and IE-I CMV proteins, to monitor CMV-CMI following kidney transplantation. A prospective longitudinal multicenter study was conducted in 86 intermediate-risk renal transplant recipients. CMV-CMI, CMV viral load, and clinical complications were monitored over 6 months post-transplantation. Ninety-five percent and 88–92% ELISpot assays were positive pre- and post-transplantation, respectively. CMV-specific response was reduced following immunosuppressive treatment and increased in patients with graft rejection, indicating the ability of the ELISpot assay to monitor patients' immunosuppressive state. Interestingly, median pp65-specific response was ninefold higher in patients with self-clearing viral load compared to antivirally treated patients prior to first viral load detection (P < 0.001), suggesting that reactivity to pp65 represents a potential immunocompetence marker. Altogether, T-Track® CMV is a highly sensitive IFN-γ ELISpot assay, suitable for the immunomonitoring of CMV-seropositive renal transplant recipients, and with a potential use for the risk assessment of CMV-related clinical complications (ClinicalTrials.gov Identifier: NCT02083042). KW - CMV-specific cell-mediated immunity KW - cytomegalovirus KW - IFN‐γ ELISpot KW - immunomonitoring KW - in vitro diagnostic KW - kidney or renal transplantation Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-221468 VL - 31 ER -