VAMP2 and synaptotagmin mobility in chromaffin granule membranes: implications for regulated exocytosis.

ABSTRACT: Granule-plasma membrane docking and fusion can only occur when proteins that enable these reactions are present at the granule-plasma membrane contact. Thus, the mobility of granule membrane proteins may influence docking and membrane fusion. We measured the mobility of vesicle associated membrane protein 2 (VAMP2), synaptotagmin 1 (Syt1), and synaptotagmin 7 (Syt7) in chromaffin granule membranes in living chromaffin cells. We used a method that is not limited by standard optical resolution. A bright flash of strongly decaying evanescent field produced by total internal reflection was used to photobleach GFP-labeled proteins in the granule membrane. Fluorescence recovery occurs as unbleached protein in the granule membrane distal from the glass interface diffuses into the more bleached pr

SUBMITTER: Abbineni PS 

PROVIDER: S-EPMC9265163 | biostudies-literature | 2022 May

REPOSITORIES: biostudies-literature