Membrane Docking of the Synaptotagmin 7 C2A Domain: Electron Paramagnetic Resonance Measurements Show Contributions from Two Membrane Binding Loops.

ABSTRACT: The synaptotagmin (Syt) family of proteins plays an important role in vesicle docking and fusion during Ca(2+)-induced exocytosis in a wide variety of cell types. Its role as a Ca(2+) sensor derives primarily from its two C2 domains, C2A and C2B, which insert into anionic lipid membranes upon binding Ca(2+). Syt isoforms 1 and 7 differ significantly in their Ca(2+) sensitivity; the C2A domain from Syt7 binds Ca(2+) and membranes much more tightly than the C2A domain from Syt1, at least in part because of greater contributions from the hydrophobic effect. While the structure and membrane activity of Syt1 have been extensively studied, the structural origins of differences between Syt1 and Syt7 are unknown. This study used site-directed spin labeling and electron paramagnetic resonance spect

SUBMITTER: Osterberg JR 

PROVIDER: S-EPMC4630001 | biostudies-literature | 2015 Sep

REPOSITORIES: biostudies-literature