Complexin Binding to Membranes and Acceptor t-SNAREs Explains Its Clamping Effect on Fusion.

ABSTRACT: Complexin-1 is a SNARE effector protein that decreases spontaneous neurotransmitter release and enhances evoked release. Complexin binds to the fully assembled four-helical neuronal SNARE core complex as revealed in competing molecular models derived from x-ray crystallography. Presently, it is unclear how complexin binding to the postfusion complex accounts for its effects upon spontaneous and evoked release in vivo. Using a combination of spectroscopic and imaging methods, we characterize in molecular detail how complexin binds to the 1:1 plasma membrane t-SNARE complex of syntaxin-1a and SNAP-25 while simultaneously binding the lipid bilayer at both its N- and C-terminal ends. These interactions are cooperative, and binding to the prefusion acceptor t-SNARE complex is stronger than to t

SUBMITTER: Zdanowicz R 

PROVIDER: S-EPMC5607037 | biostudies-literature | 2017 Sep

REPOSITORIES: biostudies-literature