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Maria Mittelbrunn Miguel Vicente‐Manzanares Francisco Sánchez‐Madrid 《Traffic (Copenhagen, Denmark)》2015,16(4):327-337
Exosomes are extracellular vesicles that transport different molecules between cells. They are formed and stored inside multivesicular bodies (MVB) until they are released to the extracellular environment. MVB fuse along the plasma membrane, driving non‐polarized secretion of exosomes. However, polarized signaling potentially directs MVBs to a specific point in the plasma membrane to mediate a focal delivery of exosomes. MVB polarization occurs across a broad set of cellular situations, e.g. in immune and neuronal synapses, cell migration and in epithelial sheets. In this review, we summarize the current state of the art of polarized MVB docking and the specification of secretory sites at the plasma membrane. The current view is that MVB positioning and subsequent exosome delivery requires a polarizing, cytoskeletal dependent‐trafficking mechanism. In this context, we propose scenarios in which biochemical and mechanical signals could drive the polarized delivery of exosomes in highly polarized cells, such as lymphocytes, neurons and epithelia. 相似文献
996.
Timothy C. Barnett Jason N. Cole Tania Rivera‐Hernandez Anna Henningham James C. Paton Victor Nizet Mark J. Walker 《Cellular microbiology》2015,17(12):1721-1741
Group A Streptococcus (Streptococcus pyogenes), group B Streptococcus (Streptococcus agalactiae) and Streptococcus pneumoniae (pneumococcus) are host‐adapted bacterial pathogens among the leading infectious causes of human morbidity and mortality. These microbes and related members of the genus Streptococcus produce an array of toxins that act against human cells or tissues, resulting in impaired immune responses and subversion of host physiological processes to benefit the invading microorganism. This toxin repertoire includes haemolysins, proteases, superantigens and other agents that ultimately enhance colonization and survival within the host and promote dissemination of the pathogen. 相似文献
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A better understanding of how ecological novelty influences interactions in new combinations of species is key for predicting interaction outcomes, and can help focus conservation and management efforts on preventing the introduction of novel organisms or species (including invasive species, GMOs, synthetic organisms, resurrected species and emerging pathogens) that seem particularly ‘risky’ for resident species. Here, we consider the implications of different degrees of eco‐evolutionary experience of interacting resident and non‐resident species, define four qualitative risk categories for estimating the probability of successful establishment and impact of novel species and discuss how the effects of novelty change over time. Focusing then on novel predator–prey interactions, we argue that novelty entails density‐dependent advantages for non‐resident species, with their largest effects often being at low prey densities. This is illustrated by a comparison of predator functional responses and prey predation risk curves between novel species and ecologically similar resident species, and raises important issues for the conservation of endangered resident prey species. 相似文献
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Anna Stincone Alessandro Prigione Thorsten Cramer Mirjam M. C. Wamelink Kate Campbell Eric Cheung Viridiana Olin‐Sandoval Nana‐Maria Grüning Antje Krüger Mohammad Tauqeer Alam Markus A. Keller Michael Breitenbach Kevin M. Brindle Joshua D. Rabinowitz Markus Ralser 《Biological reviews of the Cambridge Philosophical Society》2015,90(3):927-963
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Productivity enhances benthic species richness along an oligotrophic Indian Ocean continental margin 下载免费PDF全文
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Latitudinal gradients in the productivity of European migrant warblers have not shifted northwards during a period of climate change 下载免费PDF全文