Genstein4; Graca Raposo5; D. Michiel Pegtel6; Guillaume van Niel7 Division of Medicinal Chemistry, Amsterdam Institute for Molecules Medicines and Systems, VU University Amsterdam, de Boelelaan 1108, 1081 HZ Amsterdam, The Netherlands., Amsterdam, The Netherlands; 2INSERM U894 Centre de Psychiatrie et Neurosciences, Paris, France; 3Institut Curie, PSL Study University, CNRS, UMR144, Paris, France., Paris, France; 4Institut Curie, PSL Research University, CNRS, UMR144, Paris, France., paris, France; 5Institut Curie, Paris, France; 6Exosome Research Group, Dept. Pathology, Cancer Center Amsterdam, VU University Healthcare Center, de Boelelaan 1118, 1081 HV Amsterdam, The Netherlands; 7CNRS, Paris, FranceUniversity of Southern California, Los Angeles, USABackground: Exosomes correspond to intraluminal vesicles of multivesicular endosomes (MVE) which can be released just after fusion of MVEs using the plasma membrane. In spite of the increasing interest in exosome functions, specially in disease, the mechanisms responsible for their secretion are far from becoming completely understood. This expertise is but capital as it is the 1st step that UCH Proteins web controls this intercellular mode of communication. MVEs are extremely dynamic endosomal organelles that may be transported by several molecular motors and interact with other intracellular organelles during their maturation course of action. Within this study, we investigated the influence of tuning MVE-transport and their interactions with other organelles, notably the ER and lysosomes, on exosome release. Approaches: To study exosome release, we profited from CD63-pHluorin, a pH-sensitive reporter of MVE-plasma membrane fusion that could be imaged by live-cell TIRF microscopy. We combined this live imaging method with correlative light electron Endoplasmic Reticulum To Nucleus Signaling 1 (ERN1/IRE1) Proteins manufacturer microscopy (CLEM) and conventional EV analysis techniques. Applying these approaches, we investigated the role of MVE-associated Rab-GTPases, molecular motors and inter-organelle contacts in the regulation of MVE targeting and fusion using the plasma membrane. Final results: Reside imaging of MVE-plasma membrane fusion revealed subpopulations of MVEs that have distinct skills to release exosomes. Combined with conventional EV analysis procedures this method identified endosomal molecular motors involved within the targeting of MVEs towards the plasma membrane for fusion. Additionally, manipulating the interactions of MVEs using the Endoplasmic reticulum affects their capability to fuse not simply with lysosomes but also with all the plasma membrane. Summary/Conclusion: Our data show the interdependency of several crucial mechanisms that modulate MVE homeostasis, inter-organelle contacts and motility, and subsequent exosome release. An increased understanding of the processes involved in MVE exocytosis may possibly contribute to the improvement of novel approaches to target and manipulate exosomal communication in disease. Funding: This study was funded by Fondation pour la Recherche Medicale (AJE20160635884) to G.v.N., the EMBO ALTF 1383-2014 to F.V., the Fondation ARC fellowship (PJA 20161204808) to F.V., LabEx celthisphybio to G.v.N. and F.V., the CCA travel grant to M.B. and also the curie International PhD system to R.P.Background: Most bacteria release extracellular vesicles (EVs). Recent research have discovered these vesicles are capable of gene delivery; on the other hand, the consequences of vesicle-mediated transfer around the patterns and rates of gene flow inside microbial communities remains unclear. Previous research haven’t determined the impact of bot.
