The mesoscale organization of syntaxin 1A and SNAP25 is determined by SNARE-SNARE-interactions

  1. Jasmin Mertins
  2. Jérôme Finke
  3. Ricarda Antonia Sies
  4. Kerstin Rink
  5. Jan Hasenauer
  6. Thorsten Lang  Is a corresponding author
  1. University of Bonn, Germany
  2. Heidelberg University Biochemistry Center, Germany

Abstract

SNARE proteins have been described as the effectors of fusion events in the secretory pathway more than two decades ago. The strong interactions between SNARE-domains are clearly important in membrane fusion, but it is unclear whether they are involved in any other cellular processes. Here, we analyzed two classical SNARE proteins, syntaxin 1A and SNAP25. Although they are supposed to be engaged in tight complexes, we surprisingly find them largely segregated in the plasma membrane. Syntaxin 1A only occupies a small fraction of the plasma membrane area. Yet, we find it is able to redistribute the far more abundant SNAP25 on the mesoscale by gathering crowds of SNAP25 molecules onto syntaxin-clusters in a SNARE-domain dependent manner. Our data suggests that SNARE-domain interactions are not only involved in driving membrane fusion on the nanoscale, but also play an important role in controlling the general organization of proteins on the mesoscale. Further, we propose this mechanisms preserves active syntaxin 1A-SNAP25 complexes at the plasma membrane.

Data availability

All data generated or analysed during this study are included in the manuscript and supporting files.

Article and author information

Author details

  1. Jasmin Mertins

    Department of Membrane Biochemistry, Life and Medical Sciences Institute, University of Bonn, Bonn, Germany
    Competing interests
    The authors declare that no competing interests exist.
  2. Jérôme Finke

    Department of Membrane Biochemistry, Life and Medical Sciences Institute, University of Bonn, Bonn, Germany
    Competing interests
    The authors declare that no competing interests exist.
  3. Ricarda Antonia Sies

    Department of Membrane Biochemistry, Life and Medical Sciences Institute, University of Bonn, Bonn, Germany
    Competing interests
    The authors declare that no competing interests exist.
  4. Kerstin Rink

    Heidelberg University Biochemistry Center, Heidelberg, Germany
    Competing interests
    The authors declare that no competing interests exist.
  5. Jan Hasenauer

    Department of Membrane Biochemistry, Life and Medical Sciences Institute, University of Bonn, Bonn, Germany
    Competing interests
    The authors declare that no competing interests exist.
  6. Thorsten Lang

    Department of Membrane Biochemistry, Life and Medical Sciences Institute, University of Bonn, Bonn, Germany
    For correspondence
    thorsten.lang@uni-bonn.de
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-9128-0137

Funding

Deutsche Forschungsgemeinschaft (Project Number 112927078)

  • Thorsten Lang

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Reviewing Editor

  1. Axel T Brunger, Stanford University School of Medicine, Howard Hughes Medical Institute, United States

Publication history

  1. Received: April 8, 2021
  2. Accepted: November 14, 2021
  3. Accepted Manuscript published: November 15, 2021 (version 1)
  4. Version of Record published: November 29, 2021 (version 2)

Copyright

© 2021, Mertins 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. Jasmin Mertins
  2. Jérôme Finke
  3. Ricarda Antonia Sies
  4. Kerstin Rink
  5. Jan Hasenauer
  6. Thorsten Lang
(2021)
The mesoscale organization of syntaxin 1A and SNAP25 is determined by SNARE-SNARE-interactions
eLife 10:e69236.
https://doi.org/10.7554/eLife.69236
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