1. Structural Biology and Molecular Biophysics
  2. Cell Biology
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9Å structure of the COPI coat reveals that the Arf1 GTPase occupies two contrasting molecular environments

  1. Svetlana O Dodonova
  2. Patrick Aderhold
  3. Juergen Kopp
  4. Iva Ganeva
  5. Simone Röhling
  6. Wim J Hagen
  7. Irmgard Sinning
  8. Felix Wieland
  9. John AG Briggs  Is a corresponding author
  1. European Molecular Biology Laboratory, Germany
  2. Heidelberg University, Germany
Research Article
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Cite this article as: eLife 2017;6:e26691 doi: 10.7554/eLife.26691

Abstract

COPI coated vesicles mediate trafficking within the Golgi apparatus and between the Golgi and the endoplasmic reticulum. Assembly of a COPI coated vesicle is initiated by the small GTPase Arf1 that recruits the coatomer complex to the membrane, triggering polymerization and budding. The vesicle uncoats before fusion with a target membrane. Coat components are structurally conserved between COPI and clathrin/adaptor proteins. Using cryo-electron tomography and subtomogram averaging, we determined the structure of the COPI coat assembled on membranes in vitro at 9 Å resolution. We also obtained a 2.57 Å resolution crystal structure of βδ-COP. By combining these structures we built a molecular model of the coat. We additionally determined the coat structure in the presence of ArfGAP proteins that regulate coat dissociation. We found that Arf1 occupies contrasting molecular environments within the coat, leading us to hypothesize that some Arf1 molecules may regulate vesicle assembly while others regulate coat disassembly.

Article and author information

Author details

  1. Svetlana O Dodonova

    Structural and Computational Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-5002-8138
  2. Patrick Aderhold

    Heidelberg University Biochemistry Center, Heidelberg University, Heidelberg, Germany
    Competing interests
    The authors declare that no competing interests exist.
  3. Juergen Kopp

    Heidelberg University Biochemistry Center, Heidelberg University, Heidelberg, Germany
    Competing interests
    The authors declare that no competing interests exist.
  4. Iva Ganeva

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

    Heidelberg University Biochemistry Center, Heidelberg University, Heidelberg, Germany
    Competing interests
    The authors declare that no competing interests exist.
  6. Wim J Hagen

    Structural and Computational Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-6229-2692
  7. Irmgard Sinning

    Heidelberg University Biochemistry Center, Heidelberg University, Heidelberg, Germany
    Competing interests
    The authors declare that no competing interests exist.
  8. Felix Wieland

    Heidelberg University Biochemistry Center, Heidelberg University, Heidelberg, Germany
    Competing interests
    The authors declare that no competing interests exist.
  9. John AG Briggs

    Structural and Computational Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany
    For correspondence
    john.briggs@embl.de
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-3990-6910

Funding

Deutsche Forschungsgemeinschaft (SFB638 (A16))

  • Felix Wieland
  • John AG Briggs

Deutsche Forschungsgemeinschaft (SFB638 (Z4))

  • Irmgard Sinning

Deutsche Forschungsgemeinschaft (WI 654/12-1)

  • Felix Wieland

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

Reviewing Editor

  1. Margaret S. Robinson, University of Cambridge, United Kingdom

Publication history

  1. Received: March 10, 2017
  2. Accepted: June 9, 2017
  3. Accepted Manuscript published: June 16, 2017 (version 1)
  4. Version of Record published: June 23, 2017 (version 2)

Copyright

© 2017, Dodonova 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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