Myosin VI and branched actin filaments mediate membrane constriction and fission of melanosomal tubule carriers.

ABSTRACT: Vesicular and tubular transport intermediates regulate organellar cargo dynamics. Transport carrier release involves local and profound membrane remodeling before fission. Pinching the neck of a budding tubule or vesicle requires mechanical forces, likely exerted by the action of molecular motors on the cytoskeleton. Here, we show that myosin VI, together with branched actin filaments, constricts the membrane of tubular carriers that are then released from melanosomes, the pigment containing lysosome-related organelles of melanocytes. By combining superresolution fluorescence microscopy, correlative light and electron microscopy, and biochemical analyses, we find that myosin VI motor activity mediates severing by constricting the neck of the tubule at specific melanosomal subdomains. Pinch

SUBMITTER: Ripoll L 

PROVIDER: S-EPMC6080934 | biostudies-literature | 2018 Aug

REPOSITORIES: biostudies-literature