1. Structural Biology and Molecular Biophysics
  2. Neuroscience
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Complexin induces a conformational change at the membrane-proximal C-terminal end of the SNARE complex

  1. Ucheor B Choi
  2. Minglei Zhao
  3. Yunxiang Zhang
  4. Ying Lai
  5. Axel T Brunger  Is a corresponding author
  1. Howard Hughes Medical Institute, Stanford University, United States
Research Article
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Cite this article as: eLife 2016;5:e16886 doi: 10.7554/eLife.16886

Abstract

Complexin regulates spontaneous release and activates Ca2+-triggered neurotransmitter release, yet the molecular mechanisms are still unclear. Here we performed single molecule fluorescence resonance energy transfer experiments and uncovered two conformations of complexin-1 when bound to the ternary SNARE complex. In the cis conformation, complexin-1 induces a conformational change at the membrane-proximal C-terminal end of the ternary SNARE complex that specifically depends on the N-terminal, accessory, and central domains of complexin-1. Together with a previous study involving αSNAP, these data suggest that the C-terminal end of the ternary SNARE complex is more plastic than the N-terminal half. In the trans conformation, complexin-1 can simultaneously interact with a ternary SNARE complex via the central domain and a binary SNARE complex consisting of syntaxin-1A and SNAP-25A via the accessory domain. The cis conformation may be involved in activation of synchronous neurotransmitter release, whereas both conformations may be involved in regulating spontaneous release.

Article and author information

Author details

  1. Ucheor B Choi

    Departments of Molecular and Cellular Physiology, Neurology and Neurological Sciences, Photon Science, and Structural Biology, Howard Hughes Medical Institute, Stanford University, Stanford, United States
    Competing interests
    No competing interests declared.
  2. Minglei Zhao

    Departments of Molecular and Cellular Physiology, Neurology and Neurological Sciences, Photon Science, and Structural Biology, Howard Hughes Medical Institute, Stanford University, Stanford, United States
    Competing interests
    No competing interests declared.
  3. Yunxiang Zhang

    Departments of Molecular and Cellular Physiology, Neurology and Neurological Sciences, Photon Science, and Structural Biology, Howard Hughes Medical Institute, Stanford University, Stanford, United States
    Competing interests
    No competing interests declared.
  4. Ying Lai

    Departments of Molecular and Cellular Physiology, Neurology and Neurological Sciences, Photon Science, and Structural Biology, Howard Hughes Medical Institute, Stanford University, Stanford, United States
    Competing interests
    No competing interests declared.
  5. Axel T Brunger

    Departments of Molecular and Cellular Physiology, Neurology and Neurological Sciences, Photon Science, and Structural Biology, Howard Hughes Medical Institute, Stanford University, Stanford, United States
    For correspondence
    brunger@stanford.edu
    Competing interests
    Axel T Brunger, Reviewing editor, eLife.

Reviewing Editor

  1. Antoine M van Oijen, University of Groningen, Netherlands

Publication history

  1. Received: April 13, 2016
  2. Accepted: June 1, 2016
  3. Accepted Manuscript published: June 2, 2016 (version 1)
  4. Version of Record published: June 29, 2016 (version 2)

Copyright

© 2016, Choi et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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