1. Structural Biology and Molecular Biophysics
  2. Neuroscience

Synaptotagmin-1 C2B domain interacts simultaneously with SNAREs and membranes to promote membrane fusion

  1. Shen Wang
  2. Yun Li
  3. Cong Ma  Is a corresponding author
  1. Huazhong University of Science and Technology, China
https://doi.org/10.7554/eLife.14211
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  1. Shen Wang
  2. Yun Li
  3. Cong Ma
(2016)
Synaptotagmin-1 C2B domain interacts simultaneously with SNAREs and membranes to promote membrane fusion
eLife 5:e14211.
https://doi.org/10.7554/eLife.14211
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Abstract

Synaptotagmin-1 (Syt1) acts as a Ca2+ sensor for neurotransmitter release through its C2 domains. It has been proposed that Syt1 promotes SNARE-dependent fusion mainly through its C2B domain, but the underlying mechanism is poorly understood. In this study, we show that the C2B domain interacts simultaneously with acidic membranes and SNARE complexes via the top Ca2+-binding loops, the side polybasic patch, and the bottom face in response to Ca2+. Disruption of the simultaneous interactions completely abrogates the triggering activity of the C2B domain in liposome fusion. We hypothesize that the simultaneous interactions endow the C2B domain with an ability to deform local membranes, and this membrane-deformation activity might underlie the functional significance of the Syt1 C2B domain in vivo.

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Author details

  1. Shen Wang

    Key Laboratory of Molecular Biophysics of the Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, China
    Competing interests
    The authors declare that no competing interests exist.

  2. Yun Li

    Key Laboratory of Molecular Biophysics of the Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, China
    Competing interests
    The authors declare that no competing interests exist.

  3. Cong Ma

    Key Laboratory of Molecular Biophysics of the Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, China
    For correspondence
    cong.ma@hust.edu.cn
    Competing interests
    The authors declare that no competing interests exist.

Copyright

© 2016, Wang 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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  1. Shen Wang
  2. Yun Li
  3. Cong Ma
(2016)
Synaptotagmin-1 C2B domain interacts simultaneously with SNAREs and membranes to promote membrane fusion
eLife 5:e14211.
https://doi.org/10.7554/eLife.14211

Share this article

https://doi.org/10.7554/eLife.14211

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