Format

Send to:

Choose Destination
See comment in PubMed Commons below
Biophys J. 2013 Dec 3;105(11):2507-16. doi: 10.1016/j.bpj.2013.10.029.

Conformational dynamics of calcium-triggered activation of fusion by synaptotagmin.

Author information

  • 1Department of Cell Biology, Yale University School of Medicine, New Haven, Connecticut. Electronic address: shyam.krishnakumar@yale.edu.

Abstract

Synaptotagmin triggers rapid exocytosis of neurotransmitters from synaptic vesicles in response to Calcium (Ca(2+)) ions. Here, we use a novel Nanodisc-based system, designed to be a soluble mimetic of the clamped synaptic vesicle-bilayer junction, combined with fluorescence resonance energy transfer (FRET) spectroscopy to monitor the structural relationships among SNAREs (soluble N-ethylmaleimide-sensitive factor attachment protein receptor), Synaptotagmin C2 domains, and the lipid bilayer in real time during the Ca(2+)-activation process. We report that Synaptotagmin remains rigidly fixed on the partially assembled SNARE complex with no detectable internal rearrangement of its C2 domains, even as it rapidly inserts into the bilayer. We hypothesize that this straightforward, one-step physical mechanism could explain how this Ca(2+)- sensor rapidly activates neurotransmitter release from the clamped state.

Copyright © 2013 Biophysical Society. Published by Elsevier Inc. All rights reserved.

PMID:
24314081
[PubMed - indexed for MEDLINE]
PMCID:
PMC3853086
Free PMC Article
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Elsevier Science Icon for PubMed Central
    Loading ...
    Write to the Help Desk