The CryoEM structure of the Saccharomyces cerevisiae ribosome maturation factor Rea1

  1. Piotr Sosnowski  Is a corresponding author
  2. Linas Urnavicius
  3. Andreas Boland
  4. Robert Fagiewicz
  5. Johan Busselez
  6. Gabor Papai
  7. Helgo Schmidt  Is a corresponding author
  1. Institut de Génétique et de Biologie Moléculaire et Cellulaire, France
  2. MRC Laboratory of Molecular Biology, United Kingdom

Abstract

The biogenesis of 60S ribosomal subunits is initiated in the nucleus where rRNAs and proteins form pre-60S particles. These pre-60S particles mature by transiently interacting with various assembly factors. The ~5000 amino-acid AAA+ ATPase Rea1 (or Midasin) generates force to mechanically remove assembly factors from pre-60S particles, which promotes their export to the cytosol. Here we present three Rea1 cryoEM structures. We visualize the Rea1 engine, a hexameric ring of AAA+ domains, and identify an α-helical bundle of AAA2 as a major ATPase activity regulator. The α-helical bundle interferes with nucleotide induced conformational changes that create a docking site for the substrate binding MIDAS domain on the AAA+ ring. Furthermore, we reveal the architecture of the Rea1 linker, which is involved in force generation and extends from the AAA+ ring. The data presented here provide insights into the mechanism of one of the most complex ribosome maturation factors.

Data availability

The atomic coordinates for the Rea1 AAA+ ring and the Rea1 linker in the ADP state have been deposited with PDB IDs 6HYP and 6HYD, respectively. The accession codes for the Rea1 and Rea1_ΔAAA2L-H2α models in the AMPPNP state are 6I26 and 6I27, respectively. The accession codes for the cryoEM maps of the Rea1 AAA+ ring and the Rea1 linker in the ADP state are EMD-0309 and EMD-0308, respectively. The accession code for the unsharpened cryoEM map of the Rea1 AAA+ ring in the ADP state is EMD-0330. The cryoEM maps of the Rea1 and Rea1_ΔAAA2L-H2α AMPPNP states have the EMD accession codes EMD-0328 and EMD-0329, respectively.

The following data sets were generated

Article and author information

Author details

  1. Piotr Sosnowski

    Institut de Génétique et de Biologie Moléculaire et Cellulaire, Illkirch, France
    For correspondence
    sosnowsp@igbmc.fr
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-4902-9560
  2. Linas Urnavicius

    Division of Structural Studies, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  3. Andreas Boland

    Division of Structural Studies, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-1218-6714
  4. Robert Fagiewicz

    Institut de Génétique et de Biologie Moléculaire et Cellulaire, Illkirch, France
    Competing interests
    The authors declare that no competing interests exist.
  5. Johan Busselez

    Institut de Génétique et de Biologie Moléculaire et Cellulaire, Illkirch, France
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-4078-1265
  6. Gabor Papai

    Institut de Génétique et de Biologie Moléculaire et Cellulaire, Illkirch, France
    Competing interests
    The authors declare that no competing interests exist.
  7. Helgo Schmidt

    Institut de Génétique et de Biologie Moléculaire et Cellulaire, Illkirch, France
    For correspondence
    schmidth@igbmc.fr
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-8004-8316

Funding

HS-ATIP-avenir grant (CDP 0B1INSB-HS-9ADO1051)

  • Helgo Schmidt

LabEX startup grant (GIE I-LABEX-HS)

  • Helgo Schmidt

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

Reviewing Editor

  1. Andres E Leschziner, University of California, San Diego, United States

Publication history

  1. Received: June 12, 2018
  2. Accepted: November 8, 2018
  3. Accepted Manuscript published: November 21, 2018 (version 1)
  4. Accepted Manuscript updated: November 26, 2018 (version 2)
  5. Version of Record published: December 7, 2018 (version 3)

Copyright

© 2018, Sosnowski 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. Piotr Sosnowski
  2. Linas Urnavicius
  3. Andreas Boland
  4. Robert Fagiewicz
  5. Johan Busselez
  6. Gabor Papai
  7. Helgo Schmidt
(2018)
The CryoEM structure of the Saccharomyces cerevisiae ribosome maturation factor Rea1
eLife 7:e39163.
https://doi.org/10.7554/eLife.39163

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