First Author | Wen PJ | Year | 2016 |
Journal | Nat Commun | Volume | 7 |
Pages | 12604 | PubMed ID | 27576662 |
Mgi Jnum | J:241906 | Mgi Id | MGI:5903838 |
Doi | 10.1038/ncomms12604 | Citation | Wen PJ, et al. (2016) Actin dynamics provides membrane tension to merge fusing vesicles into the plasma membrane. Nat Commun 7:12604 |
abstractText | Vesicle fusion is executed via formation of an Omega-shaped structure (Omega-profile), followed by closure (kiss-and-run) or merging of the Omega-profile into the plasma membrane (full fusion). Although Omega-profile closure limits release but recycles vesicles economically, Omega-profile merging facilitates release but couples to classical endocytosis for recycling. Despite its crucial role in determining exocytosis/endocytosis modes, how Omega-profile merging is mediated is poorly understood in endocrine cells and neurons containing small approximately 30-300 nm vesicles. Here, using confocal and super-resolution STED imaging, force measurements, pharmacology and gene knockout, we show that dynamic assembly of filamentous actin, involving ATP hydrolysis, N-WASP and formin, mediates Omega-profile merging by providing sufficient plasma membrane tension to shrink the Omega-profile in neuroendocrine chromaffin cells containing approximately 300 nm vesicles. Actin-directed compounds also induce Omega-profile accumulation at lamprey synaptic active zones, suggesting that actin may mediate Omega-profile merging at synapses. These results uncover molecular and biophysical mechanisms underlying Omega-profile merging. |