Modulating vesicle priming reveals that vesicle immobilization is necessary but not sufficient for fusion-competence.

ABSTRACT: In neurons and neuroendocrine cells, docked vesicles need to undergo priming to become fusion competent. Priming is a multi-step process that was shown to be associated with vesicle immobilization. However, it is not known whether vesicle immobilization is sufficient to acquire complete fusion competence. To extend our understanding of the physical manifestation of vesicle priming, we took advantage of tomosyn, a SNARE-related protein that specifically inhibits vesicle priming, and measured its effect on vesicle dynamics in live chromaffin cells using total internal reflection fluorescence microscopy. We show here that while in control cells vesicles undergo immobilization before fusion, vesicle immobilization is attenuated in tomosyn overexpressing cells. This in turn increases the turnov

SUBMITTER: Yizhar O 

PROVIDER: S-EPMC2444019 | biostudies-literature | 2008 Jul

REPOSITORIES: biostudies-literature