HOPS recognizes each SNARE, assembling ternary trans-complexes for rapid fusion upon engagement with the 4th SNARE

  1. Hongki Song
  2. Amy S Orr
  3. Miriam Lee
  4. Max E Harner
  5. William T Wickner  Is a corresponding author
  1. Geisel School of Medicine at Dartmouth, United States

Abstract

Yeast vacuole fusion requires R-SNARE, Q-SNAREs, and HOPS. A HOPS SM-family subunit binds the R- and Qa-SNAREs. We now report that HOPS binds each of the four SNAREs. HOPS catalyzes fusion when the Q-SNAREs are not pre-assembled, ushering them into a functional complex. Co-incubation of HOPS, proteoliposomes bearing R-SNARE, and proteoliposomes with any two Q-SNAREs yields a rapid-fusion complex with 3 SNAREs in a trans-assembly. The missing Q-SNARE then induces sudden fusion. HOPS can 'template' SNARE complex assembly through SM recognition of R- and Qa-SNAREs. Though the Qa-SNARE is essential for spontaneous SNARE assembly, HOPS also assembles a rapid-fusion complex between R- and QbQc-SNARE proteoliposomes in the absence of Qa-SNARE, awaiting Qa for fusion. HOPS-dependent fusion is saturable at low concentrations of each Q-SNARE, showing binding site functionality. HOPS thus tethers membranes, recognizes the R-SNARE, and recognizes Qa or Qb/Qc SNAREs, assembling R+Qa or R+QbQc rapid fusion intermediates.

Data availability

All data generated or analyzed during this study are included in the manuscript and supporting files. Source data files have been provided for Figures 1, 3, 4, 5, 6, 8, 9 and 10.N/A

Article and author information

Author details

  1. Hongki Song

    Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-3761-5434
  2. Amy S Orr

    Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Miriam Lee

    Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Max E Harner

    Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-5513-1046
  5. William T Wickner

    Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, United States
    For correspondence
    William.T.Wickner@dartmouth.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-8431-0468

Funding

National Institutes of Health (R35GM118037)

  • William T Wickner

Deutsche Forschungsgemeinschaft (HA 7730/2-1)

  • Max E Harner

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

Reviewing Editor

  1. Yongli Zhang, Yale University School of Medicine, United States

Version history

  1. Received: November 13, 2019
  2. Accepted: January 19, 2020
  3. Accepted Manuscript published: January 21, 2020 (version 1)
  4. Version of Record published: January 31, 2020 (version 2)

Copyright

© 2020, Song 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. Hongki Song
  2. Amy S Orr
  3. Miriam Lee
  4. Max E Harner
  5. William T Wickner
(2020)
HOPS recognizes each SNARE, assembling ternary trans-complexes for rapid fusion upon engagement with the 4th SNARE
eLife 9:e53559.
https://doi.org/10.7554/eLife.53559

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https://doi.org/10.7554/eLife.53559

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