1. Structural Biology and Molecular Biophysics
  2. Cell Biology
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The Caenorhabditis elegans protein SAS-5 forms large oligomeric assemblies critical for centriole formation

  1. Kacper B Rogala
  2. Nicola J Dynes
  3. Georgios N Hatzopoulos
  4. Jun Yan
  5. Sheng Kai Pong
  6. Carol V Robinson
  7. Charlotte M Deane
  8. Pierre Gönczy
  9. Ioannis Vakonakis  Is a corresponding author
  1. University of Oxford, United Kingdom
  2. Swiss Federal Institute of Technology, Switzerland
Research Article
  • Cited 26
  • Views 2,061
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Cite this article as: eLife 2015;4:e07410 doi: 10.7554/eLife.07410

Abstract

Centrioles are microtubule-based organelles crucial for cell division, sensing and motility. In C. elegans, the onset of centriole formation requires notably the proteins SAS-5 and SAS-6, which have functional homologs across eukaryotic evolution. Whereas the molecular architecture of SAS-6 and its role in initiating centriole formation are well understood, the mechanisms by which SAS-5 and its relatives function is unclear. Here, we combine biophysical and structural analysis to uncover the architecture of SAS-5 and examine its functional implications in vivo. Our work reveals that two distinct self-associating domains are necessary to form higher-order oligomers of SAS-5: a trimeric coiled coil and a novel globular dimeric Implico domain. Disruption of either domain leads to centriole duplication failure in worm embryos, indicating that large SAS-5 assemblies are necessary for function in vivo.

Article and author information

Author details

  1. Kacper B Rogala

    Department of Biochemistry, University of Oxford, Oxford, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.

  2. Nicola J Dynes

    Swiss Institute for Experimental Cancer Research, School of Life Sciences, Swiss Federal Institute of Technology, Lausanne, Switzerland
    Competing interests
    The authors declare that no competing interests exist.

  3. Georgios N Hatzopoulos

    Department of Biochemistry, University of Oxford, Oxford, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.

  4. Jun Yan

    Department of Chemistry, University of Oxford, Oxford, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.

  5. Sheng Kai Pong

    Swiss Institute for Experimental Cancer Research, School of Life Sciences, Swiss Federal Institute of Technology, Lausanne, Switzerland
    Competing interests
    The authors declare that no competing interests exist.

  6. Carol V Robinson

    Department of Chemistry, University of Oxford, Oxford, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.

  7. Charlotte M Deane

    Department of Statistics, University of Oxford, Oxford, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.

  8. Pierre Gönczy

    Swiss Institute for Experimental Cancer Research, School of Life Sciences, Swiss Federal Institute of Technology, Lausanne, Switzerland
    Competing interests
    The authors declare that no competing interests exist.

  9. Ioannis Vakonakis

    Department of Biochemistry, University of Oxford, Oxford, United Kingdom
    For correspondence
    ioannis.vakonakis@bioch.ox.ac.uk
    Competing interests
    The authors declare that no competing interests exist.

Reviewing Editor

  1. Anthony A Hyman, Max Planck Institute of Molecular Cell Biology and Genetics, Germany

Publication history

  1. Received: March 10, 2015
  2. Accepted: May 28, 2015
  3. Accepted Manuscript published: May 29, 2015 (version 1)
  4. Version of Record published: June 18, 2015 (version 2)

Copyright

© 2015, Rogala 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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