Abstract

Selective autophagy is mediated by cargo receptors that link the cargo to the isolation membrane via interactions with Atg8 proteins. Atg8 proteins are localized to the membrane in an ubiquitin-like conjugation reaction, but how this conjugation is coupled to the presence of the cargo is unclear. Here we show that the S. cerevisiae Atg19, Atg34 and the human p62, Optineurin and NDP52 cargo receptors interact with the E3-like enzyme Atg12∼Atg5-Atg16, which stimulates Atg8 conjugation. The interaction of Atg19 with the Atg12∼Atg5-Atg16 complex is mediated by its Atg8-interacting motifs (AIMs). We identify the AIM-binding sites in the Atg5 subunit and mutation of these sites impairs selective autophagy. In a reconstituted system the recruitment of the E3 to the prApe1 cargo is sufficient to drive accumulation of conjugated Atg8 at the cargo. The interaction of the Atg12∼Atg5-Atg16 complex and Atg8 with Atg19 is mutually exclusive, which may confer directionality to the system.

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Author details

  1. Dorotea Fracchiolla

    Department of Biochemistry and Cell Biology, University of Vienna, Vienna, Austria
    Competing interests
    The authors declare that no competing interests exist.
  2. Justyna Sawa-Makarska

    Department of Biochemistry and Cell Biology, University of Vienna, Vienna, Austria
    Competing interests
    The authors declare that no competing interests exist.
  3. Bettina Zens

    Department of Biochemistry and Cell Biology, University of Vienna, Vienna, Austria
    Competing interests
    The authors declare that no competing interests exist.
  4. Anita de Ruiter

    Department of Structural and Computational Biology, University of Vienna, Vienna, Austria
    Competing interests
    The authors declare that no competing interests exist.
  5. Gabriele Zaffagnini

    Department of Structural and Computational Biology, University of Vienna, Vienna, Austria
    Competing interests
    The authors declare that no competing interests exist.
  6. Andrea Brezovich

    Department of Biochemistry and Cell Biology, University of Vienna, Vienna, Austria
    Competing interests
    The authors declare that no competing interests exist.
  7. Julia Romanov

    Department of Biochemistry and Cell Biology, University of Vienna, Vienna, Austria
    Competing interests
    The authors declare that no competing interests exist.
  8. Kathrin Runggatscher

    Department of Biochemistry and Cell Biology, University of Vienna, Vienna, Austria
    Competing interests
    The authors declare that no competing interests exist.
  9. Claudine Kraft

    Department of Biochemistry and Cell Biology, University of Vienna, Vienna, Austria
    Competing interests
    The authors declare that no competing interests exist.
  10. Bojan Zagrovic

    Department of Structural and Computational Biology, University of Vienna, Vienna, Austria
    Competing interests
    The authors declare that no competing interests exist.
  11. Sascha Martens

    Department of Biochemistry and Cell Biology, University of Vienna, Vienna, Austria
    For correspondence
    sascha.martens@univie.ac.at
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-3786-8199

Funding

European Research Council (260304)

  • Sascha Martens

European Research Council (646653)

  • Sascha Martens

European Research Council (279408)

  • Bojan Zagrovic

Austrian Science Fund (P25546-B20)

  • Sascha Martens

Austrian Science Fund (P25522-B20)

  • Claudine Kraft

Austrian Science Fund (P28113-B28)

  • Claudine Kraft

Austrian Science Fund (T724-B20)

  • Justyna Sawa-Makarska

Vienna Science and Technology Fund (VRG10-791 001)

  • Claudine Kraft

European Molecular Biology Organization (YIP)

  • Claudine Kraft
  • Sascha Martens

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

Reviewing Editor

  1. Hong Zhang, Institute of Biophysics, Chinese Academy of Sciences, China

Version history

  1. Received: June 6, 2016
  2. Accepted: November 21, 2016
  3. Accepted Manuscript published: November 23, 2016 (version 1)
  4. Version of Record published: December 8, 2016 (version 2)

Copyright

© 2016, Fracchiolla 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. Dorotea Fracchiolla
  2. Justyna Sawa-Makarska
  3. Bettina Zens
  4. Anita de Ruiter
  5. Gabriele Zaffagnini
  6. Andrea Brezovich
  7. Julia Romanov
  8. Kathrin Runggatscher
  9. Claudine Kraft
  10. Bojan Zagrovic
  11. Sascha Martens
(2016)
Mechanism of cargo-directed Atg8 conjugation during selective autophagy
eLife 5:e18544.
https://doi.org/10.7554/eLife.18544

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https://doi.org/10.7554/eLife.18544

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