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991.
Positive species interactions such as facilitation are important for enabling species to persist, especially in stressful conditions, and the nature and strength of facilitation varies along physical and biological gradients. Expansion of coastal infrastructure is creating hotspots of invasive species which can spillover into natural habitats, but the role of positive species interactions associated with biological invasions remains understudied. Theory suggests that stronger biotic pressure in natural habitats inhibits invasion success. In space-limited marine systems, sessile organisms can overcome this limiting resource by settling as an epibiont on a substrate organism – basibiont. Using a series of spatially extensive surveys, we explored the role of invasive and native basibionts in providing habitat for other invasive and native epibionts, and tested whether environmental context (i.e. if the receiving habitat was natural or artificial), altered ecological outcomes. Overall, provision of space by basibionts was more important for invasive epibionts than for native epibionts but was dependent on the environmental context. Invasive basibionts facilitated invasive epibionts in natural habitats, and appeared to be more important for native epibionts in artificial habitats respectively. Native basibionts facilitated invasive, but not native epibionts in both natural and artificial habitats. These results advance our understanding of facilitation and highlight the idiosyncratic nature of biofouling and epibiosis, and the potentially important influence of environmental context. The degree to which native habitat-forming species versus invasive habitat-forming species either do or do not facilitate other native or non-native species is a rich area for investigation. Experimental work is required to disentangle the processes underpinning these patterns. 相似文献
992.
993.
Paul Gouguet Julien Gronnier Anthony Legrand Artemis Perraki Marie-Dominique Jolivet Anne-Flore Deroubaix Sylvie German-Retana Marie Boudsocq Birgit Habenstein Sbastien Mongrand Vronique Germain 《Plant physiology》2021,185(3):632
REMORINs (REMs) are a plant-specific protein family, proposed regulators of membrane-associated molecular assemblies and well-established markers of plasma membrane nanodomains. REMs play a diverse set of functions in plant interactions with pathogens and symbionts, responses to abiotic stresses, hormone signaling and cell-to-cell communication. In this review, we highlight the established and more putative roles of REMs throughout the literature. We discuss the physiological functions of REMs, the mechanisms underlying their nanodomain-organization and their putative role as regulators of nanodomain-associated molecular assemblies. Furthermore, we discuss how REM phosphorylation may regulate their functional versatility. Overall, through data-mining and comparative analysis of the literature, we suggest how to further study the molecular mechanisms underpinning the functions of REMs. 相似文献
994.
Aline Planchon Gaëlle Durambur Jean‐Baptiste Besnier Carole Plasson Bruno Gügi Sophie Bernard Annabelle Mrieau Jean‐Paul Trouv Caroline Dubois Karine Laval Azeddine Driouich Jean‐Claude Mollet Richard Gattin 《Plant, cell & environment》2021,44(1):304-322
In Normandy, flax is a plant of important economic interest because of its fibres. Fusarium oxysporum, a telluric fungus, is responsible for the major losses in crop yield and fibre quality. Several methods are currently used to limit the use of phytochemicals on crops. One of them is the use of plant growth promoting rhizobacteria (PGPR) occurring naturally in the rhizosphere. PGPR are known to act as local antagonists to soil‐borne pathogens and to enhance plant resistance by eliciting the induced systemic resistance (ISR). In this study, we first investigated the cell wall modifications occurring in roots and stems after inoculation with the fungus in two flax varieties. First, we showed that both varieties displayed different cell wall organization and that rapid modifications occurred in roots and stems after inoculation. Then, we demonstrated the efficiency of a Bacillus subtilis strain to limit Fusarium wilt on both varieties with a better efficiency for one of them. Finally, thermo‐gravimetry was used to highlight that B. subtilis induced modifications of the stem properties, supporting a reinforcement of the cell walls. Our findings suggest that the efficiency and the mode of action of the PGPR B. subtilis is likely to be flax variety dependent. 相似文献
995.
996.
William C. Hahn Joel S. Bader Theodore P. Braun Andrea Califano Paul A. Clemons Brian J. Druker Andrew J. Ewald Haian Fu Subhashini Jagu Christopher J. Kemp William Kim Calvin J. Kuo Michael T. McManus Gordon B. Mills Xiulei Mo Nidhi Sahni Stuart L. Schreiber Jessica A. Talamas Jonathan Weissman 《Cell》2021,184(5):1142-1155
997.
Ivy-Israel Natascha M. D. Moore Carolyn E. Schwartz Tonia S. Steury Todd D. Zohdy Sarah Newbolt Chad H. Ditchkoff Stephen S. 《Evolutionary ecology》2021,35(3):513-535
Evolutionary Ecology - Body size and secondary sexual characteristics are drivers of male reproductive success among polygynous species. A gene complex found to be associated with morphology in... 相似文献
998.
Paula José Ricardo Sun Derek Pissarra Vasco Narvaez Pauline Rosa Rui Grutter Alexandra S. Sikkel Paul C. 《Coral reefs (Online)》2021,40(2):535-542
Coral Reefs - Gnathiid isopods, common fish ectoparasites, can affect fish physiology, behaviour and survival. Gnathiid juveniles emerge from the benthos to feed on fish blood. In the Caribbean,... 相似文献
999.
Alex Zaufel Sandra M.W. van de Wiel Lu Yin Günter Fauler Daphne Chien Xinzhong Dong John F. Gilmer Jennifer K. Truong Paul A. Dawson Stan F.J. van de Graaf Peter Fickert Tarek Moustafa 《生物化学与生物物理学报:疾病的分子基础》2021,1867(8):166153
IsoBAs, stereoisomers of primary and secondary BAs, are found in feces and plasma of human individuals. BA signaling via the nuclear receptor FXR is crucial for regulation of hepatic and intestinal physiology/pathophysiology. Aim: Investigate the ability of BA-stereoisomers to bind and modulate FXR under physiological/pathological conditions. Methods: Expression-profiling, luciferase-assays, fluorescence-based coactivator-association assays, administration of (iso)-BAs to WT and cholestatic mice. Results: Compared to CDCA/isoCDCA, administration of DCA/isoDCA, UDCA/isoUDCA only slightly increased mRNA expression of FXR target genes; the induction was more evident looking at pre-mRNAs. Notably, almost 50% of isoBAs were metabolized to 3-oxo-BAs within 4 h in cell-based assays, making it difficult to study their actions. FRET-based real-time monitoring of FXR activity revealed that isoCDCA>CDCA stimulated FXR, and isoDCA and isoUDCA allowed fully activated FXR to be re-stimulated by a second dose of GW4064. In vivo co-administration of a single dose of isoBAs followed by GW4064 cooperatively activated FXR, as did feeding of UDCA in a background of endogenous FXR ligands. However, in animals with biliary obstruction and concomitant loss of intestinal BAs, UDCA was unable to increase intestinal Fgf15. In contrast, mice with an impaired enterohepatic circulation of BAs (Asbt?/?, Ostα?/?), administration of UDCA was still able to induce ileal Fgf15 and repress hepatic BA-synthesis, arguing that UDCA is only effective in the presence of endogenous FXR ligands. Conclusion: Secondary (iso)BAs cooperatively activate FXR in the presence of endogenous BAs, which is important to consider in diseases linked to disturbances in BA enterohepatic cycling. 相似文献
1000.
Amino Acids - Solid-phase synthesis of cyclic, branched or side-chain-modified peptides typically involves introduction of a residue carrying a temporary side-chain protecting group that undergoes... 相似文献