Specific lid-base contacts in the 26S proteasome control the conformational switching required for substrate degradation

  1. Eric R Greene
  2. Ellen A Goodall
  3. Andres H de la Peña
  4. Mary E Matyskiela
  5. Gabriel C Lander
  6. Andreas Martin  Is a corresponding author
  1. University of California, Berkeley, United States
  2. The Scripps Research Institute, United States
  3. Celgene, United States

Abstract

The 26S proteasome is essential for proteostasis and the regulation of vital processes through ATP-dependent degradation of ubiquitinated substrates. To accomplish the multi-step degradation process, the proteasome's regulatory particle, consisting of lid and base subcomplexes, undergoes major conformational changes whose origin is unknown. Investigating the Saccharomyces cerevisiae proteasome, we found that peripheral interactions between the lid subunit Rpn5 and the base AAA+-ATPase ring are important for stabilizing the substrate-engagement-competent state and coordinating the conformational switch to processing states upon substrate engagement. Disrupting these interactions perturbs the conformational equilibrium and interferes with degradation initiation, while later processing steps remain unaffected. Similar defects in early degradation steps are observed when eliminating hydrolysis in the ATPase subunit Rpt6, whose nucleotide state seems to control proteasome conformational transitions. These results provide important insight into interaction networks that coordinate conformational changes with various stages of degradation, and how modulators of conformational equilibria may influence substrate turnover.

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. Eric R Greene

    Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    Competing interests
    No competing interests declared.
  2. Ellen A Goodall

    Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-9876-5973
  3. Andres H de la Peña

    Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, United States
    Competing interests
    No competing interests declared.
  4. Mary E Matyskiela

    Structral and Chemical Biology, Celgene, San Diego, United States
    Competing interests
    No competing interests declared.
  5. Gabriel C Lander

    Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, United States
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-4921-1135
  6. Andreas Martin

    Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    For correspondence
    a.martin@berkeley.edu
    Competing interests
    Andreas Martin, Reviewing editor, eLife.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-0923-3284

Funding

Howard Hughes Medical Institute

  • Andreas Martin

National Institutes of Health (R01-GM094497)

  • Andreas Martin

National Institutes of Health (DP2EB020402)

  • Gabriel C Lander

American Cancer Society (132279-PF-18-189-01-DMC)

  • Andres H de la Peña

Pew Charitable Trusts

  • Gabriel C Lander

National Institutes of Health (S10OD021634)

  • Gabriel C Lander

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

Reviewing Editor

  1. Franz-Ulrich Hartl, Max Planck Institute for Biochemistry, Germany

Publication history

  1. Received: June 30, 2019
  2. Accepted: November 27, 2019
  3. Accepted Manuscript published: November 28, 2019 (version 1)
  4. Version of Record published: December 13, 2019 (version 2)

Copyright

© 2019, Greene 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. Eric R Greene
  2. Ellen A Goodall
  3. Andres H de la Peña
  4. Mary E Matyskiela
  5. Gabriel C Lander
  6. Andreas Martin
(2019)
Specific lid-base contacts in the 26S proteasome control the conformational switching required for substrate degradation
eLife 8:e49806.
https://doi.org/10.7554/eLife.49806
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