VAMP-7 links granule exocytosis to actin reorganization during platelet activation.

摘要: Platelet activation results in profound morphologic changes accompanied by release of granule contents. Recent evidence indicates that fusion granules with the plasma membrane during provides auxiliary to cover growing actin structures. Yet little is known about how coupled reorganization. Vesicle-associated protein (VAMP)-7 found on platelet vesicles and possesses an N-terminal longin domain capable linking exocytosis cytoskeletal remodeling. We have evaluated platelets from VAMP-7(-/-) mice determine whether this VAMP isoform contributes spreading. demonstrated a partial defect dense impaired aggregation. α Granule was diminished both vitro vivo thrombus formation. Consistent role VAMP-7 remodeling, spreading matrices decreased compared wild-type controls. Immunoprecipitation revealed association VPS9-domain ankyrin repeat (VARP), adaptor interacts membrane-bound cytoskeleton proteins Arp2/3. VAMP-7, VARP, Arp2/3 localized periphery These studies demonstrate participates secretion suggest mechanism whereby links