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Complexin-1 enhances the on-rate of vesicle docking via simultaneous SNARE and membrane interactions.

ABSTRACT: In synaptic terminals, complexin is thought to have inhibitory and activating roles for spontaneous "mini" release and evoked synchronized neurotransmitter release, respectively. We used single vesicle-vesicle microscopy imaging to study the effect of complexin-1 on the on-rate of docking between vesicles that mimic synaptic vesicles and the plasma membrane. We found that complexin-1 enhances the on-rate of docking of synaptic vesicle mimics containing full-length synaptobrevin-2 and full-length synaptotagmin-1 to plasma membrane-mimicking vesicles containing full-length syntaxin-1A and SNAP-25A. This effect requires the C-terminal domain of complexin-1, which binds to the membrane, the presence of PS in the membrane, and the core region of complexin-1, which binds to the SNARE complex.

SUBMITTER: Diao J

PROVIDER: S-EPMC3854000 | biostudies-literature | 2013 Oct

REPOSITORIES: biostudies-literature

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Complexin-1 enhances the on-rate of vesicle docking via simultaneous SNARE and membrane interactions.

Diao Jiajie J Cipriano Daniel J DJ Zhao Minglei M Zhang Yunxiang Y Shah Sachi S Padolina Mark S MS Pfuetzner Richard A RA Brunger Axel T AT

Journal of the American Chemical Society 20131004 41

In synaptic terminals, complexin is thought to have inhibitory and activating roles for spontaneous "mini" release and evoked synchronized neurotransmitter release, respectively. We used single vesicle-vesicle microscopy imaging to study the effect of complexin-1 on the on-rate of docking between vesicles that mimic synaptic vesicles and the plasma membrane. We found that complexin-1 enhances the on-rate of docking of synaptic vesicle mimics containing full-length synaptobrevin-2 and full-length ...[more]

PMID: 24083833

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