Extracellular vesicle biogenesis and the role of Cx43 in vesicle-mediated intercellular communication. Extracellular vesicle biogenesis and the role of Cx43 in vesicle-mediated intercellular communication. Maturation of endocytic compartments includes the formation of intraluminal vesicles, which mature into multivesicular bodies; these can either fuse with the lysosome, sending their content to degradation, or with the plasma membrane, thereby releasing small vesicles, called exosomes, into the extracellular space. Additionally, microvesicles can originate from the plasma membrane by outward budding. In the recipient cells, exosomes and microvesicles can either fuse (1), be endocytosed (2), or dock with the plasma membrane (3), thereby triggering a response. The presence of Cx43 at the membrane of microvesicles and exosomes may facilitate their docking and/or allow a faster release of extracellular vesicles content into the target cell. Teresa M. Ribeiro-Rodrigues et al. J Cell Sci 2017;130:3619-3630 © 2017. Published by The Company of Biologists Ltd