Ca²⁺-Triggered Synaptic Vesicle Fusion Initiated by Release of Inhibition.

ABSTRACT: Recent structural and functional studies of the synaptic vesicle fusion machinery suggest an inhibited tripartite complex consisting of neuronal soluble N-ethylmaleimide sensitive factor attachment protein receptors (SNAREs), synaptotagmin, and complexin prior to Ca²⁺-triggered synaptic vesicle fusion. We speculate that Ca²⁺-triggered fusion commences with the release of inhibition by Ca²⁺ binding to synaptotagmin C2 domains. Subsequently, fusion is assisted by SNARE complex zippering and by active membrane remodeling properties of synaptotagmin. This additional, inhibitory role of synaptotagmin may be a general principle since other recent studies suggest that Ca²⁺ binding to extended synaptotagmin C2 domains enables lipid transport by releasing

SUBMITTER: Brunger AT 

PROVIDER: S-EPMC6056330 | biostudies-literature | 2018 Aug

REPOSITORIES: biostudies-literature