All RNAs are outdoors of vesicles (presumably in free protein complexes). Identifying RNAs which might

All RNAs are outdoors of vesicles (presumably in free protein complexes). Identifying RNAs which might be actually inside vesicle has significant implications for studying the function of exosome cargo in intercellular communication.LBO.Reside tracking of endogenous exosome communication in vivo Frederik J. Verweij1, Philippe Herbomel2, Gra Raposo3, Filippo del Bene4 and Guillaume Van Niel5 Exosomes Analysis Group Division of Pathology VU University Health-related Center Cancer Center Amsterdam (CCA), Amsterdam, The Netherlands; 2Insitut Pasteur; 3Centre National de la Recherche Scientifique and Institut Curie, PSL Research University, Paris, France; four Institut Curie, PSL Study University, CNRS, Paris, France; 5Institut Curie, PSL Investigation University, CNRS, UMR 144, Paris, France /Center for Psychiatry and NeuroscienceSFA-Characterising extracellular RNA inside and outside of vesicles Dmitry Ter-Ovanesyan1, Emma J.K. Kowal2, Aviv Regev3 and George M. ChurchIntroduction: Exosomes are a nano-sized subclass of Extracellular Vesicles (EVs), released by a wide variety of cell types, which have been implicated in numerous important physiological and pathological processes. As a consequence of the lack of suitable in vivo models, nonetheless, the in vivo dynamics and physiology of exosomes are poorly understood. Methods: We developed an animal model to study endogenous exosomes in vivo by (site-specific) expression of a hCD63-based fluorescent reporter for exosome secretion in zebrafish and applied a variety of light- and electron microscopy (LM and EM) techniques for our analysis. Final results: A mixture of light- and electron microscopy (LM and EM) tactics permitted us to observe exosome release in vivo and track a enormous pool of endogenous exosomes inside the blood flow of zebrafish embryos. Website specific expression confirmed that these exosomes originated in the Yolk Syncytial Layer (YSL), a multinucleate cell layer inbetween the yolk plus the developing embryo with important nutrient transport functions, sharing functional homologies with all the mammalian placenta. By Electron Microscopy we observed massive release of EVs in the CDK4 Purity & Documentation apical side on the YSL in to the blood flow, additional confirmingScientific System ISEVthe YSL as major supply of (CD63+ve) exosomes within the building embryo. Subsequent, we applied live imaging to track endogenous EVs inside the blood flow to identify their principal targets. CD63+ EVs exactly where preferentially interacting with endothelial cells inside the caudal vein and plexus in comparison to the caudal artery. EM revealed endocytosis of these EVs in endosomal compartments of endothelial cells. We detected an additional significant fraction of exosomes in the interstitial fluid, suggesting extravasation outside of the vasculature of YSL derived EVs. We ultimately observed active and specific endocytosis and storage of CD63+ EVs by scavenging macrophages on the caudal plexus.Summary/Conclusion: Functionally, our information could help a role for YSL derived EVs in nutrient delivery throughout development, which is our present concentrate. Altogether, these information reveal for the very first time the release, journey and target of endogenous exosomes in vivo. We propose the zebrafish embryo as a new model to study endogenous EVs in vivo which will open new avenues to unravel basic aspects in EV biology. Funding: EMBO ALTF 1383-2014; ARC PDF20160604167 ; Labex CelTisPhyBio post-doc project grants; FRM AJESunday, Might 21,Space: Metropolitan West and Centre Wrap-Up Sessions 11:051:35 a.m. Wrap Up Sessions Bradykinin Receptor MedChemExpress Clinical Speaker: Uta Erdb.