A molecular mechanism of mitotic centrosome assembly in Drosophila

  1. Paul T Conduit
  2. Jennifer H Richens
  3. Alan Wainman
  4. James Holder
  5. Catarina C Vicente
  6. Metta B Pratt
  7. Carly I Dix
  8. Zsofia A Novak
  9. Ian M Dobbie
  10. Lothar Schermelleh
  11. Jordan W Raff  Is a corresponding author
  1. University of Oxford, United Kingdom
  2. Medical Research Council Laboratory of Molecular Biology, United Kingdom

Abstract

Centrosomes comprise a pair of centrioles surrounded by pericentriolar material (PCM). The PCM expands dramatically as cells enter mitosis, but it is unclear how this occurs. Here, we show that the centriole protein Asl initiates the recruitment of DSpd-2 and Cnn to mother centrioles; both proteins then assemble into co-dependent scaffold-like structures that spread outwards from the mother centriole and recruit most, if not all, other PCM components. In the absence of either DSpd-2 or Cnn mitotic PCM assembly is diminished; in the absence of both proteins it appears to be abolished. We show that DSpd-2 helps incorporate Cnn into the PCM and that Cnn then helps maintain DSpd-2 within the PCM, creating a positive feedback loop that promotes robust PCM expansion around the mother centriole during mitosis. These observations suggest a surprisingly simple mechanism of mitotic PCM assembly in flies.

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Author details

  1. Paul T Conduit

    University of Oxford, Oxford, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  2. Jennifer H Richens

    University of Oxford, Oxford, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  3. Alan Wainman

    University of Oxford, Oxford, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  4. James Holder

    University of Oxford, Oxford, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  5. Catarina C Vicente

    University of Oxford, Oxford, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  6. Metta B Pratt

    University of Oxford, Oxford, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  7. Carly I Dix

    Medical Research Council Laboratory of Molecular Biology, Cambridge, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  8. Zsofia A Novak

    University of Oxford, Oxford, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  9. Ian M Dobbie

    University of Oxford, Oxford, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  10. Lothar Schermelleh

    University of Oxford, Oxford, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  11. Jordan W Raff

    University of Oxford, Oxford, United Kingdom
    For correspondence
    jordan.raff@path.ox.ac.uk
    Competing interests
    The authors declare that no competing interests exist.

Copyright

© 2014, Conduit 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. Paul T Conduit
  2. Jennifer H Richens
  3. Alan Wainman
  4. James Holder
  5. Catarina C Vicente
  6. Metta B Pratt
  7. Carly I Dix
  8. Zsofia A Novak
  9. Ian M Dobbie
  10. Lothar Schermelleh
  11. Jordan W Raff
(2014)
A molecular mechanism of mitotic centrosome assembly in Drosophila
eLife 3:e03399.
https://doi.org/10.7554/eLife.03399

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https://doi.org/10.7554/eLife.03399

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