Electron cryo-tomography provides insight into procentriole architecture and assembly mechanism

  1. Sam Li  Is a corresponding author
  2. Jose-Jesus Fernandez
  3. Wallace F Marshall
  4. David A Agard  Is a corresponding author
  1. University of California, San Francisco, United States
  2. Centro Nacional de Biotecnologia, CSIC, Spain

Abstract

Centriole is an essential structure with multiple functions in cellular processes. Centriole biogenesis and homeostasis is tightly regulated. Using electron cryo-tomography (cryoET) we present the structure of procentrioles from Chlamydomonas reinhardtii. We identified a set of non-tubulin components attached to the triplet microtubule (MT), many are at the junctions of tubules likely to reinforce the triplet. We describe structure of the A-C linker that bridges neighboring triplets. The structure infers that POC1 is likely an integral component of A-C linker. Its conserved WD40 β-propeller domain provides attachment sites for other A-C linker components. The twist of A-C linker results in an iris diaphragm-like motion of the triplets in the longitudinal direction of procentriole. Finally, we identified two assembly intermediates at the growing ends of procentriole allowing us to propose a model for the procentriole assembly. Our results provide a comprehensive structural framework for understanding the molecular mechanisms underpinning procentriole biogenesis and assembly.

Data availability

8 structures based on the subtomogram averaging have been deposited in the EMDB under the accession codes: EMD-9167, EMD-9168, EMD-9169, EMD-9170, EMD-9171, EMD-9172, EMD-9173, EMD-9174

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Article and author information

Author details

  1. Sam Li

    Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, United States
    For correspondence
    samli@msg.ucsf.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-0210-8192
  2. Jose-Jesus Fernandez

    Macromolecular structures, Centro Nacional de Biotecnologia, CSIC, Madrid, Spain
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-2222-3355
  3. Wallace F Marshall

    Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. David A Agard

    Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, United States
    For correspondence
    agard@msg.ucsf.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-3512-695X

Funding

Howard Hughes Medical Institute

  • David A Agard

National Institutes of Health (GM031627)

  • David A Agard

National Institutes of Health (GM118099)

  • David A Agard

National Institutes of Health (PO1 GM105537)

  • David A Agard

National Institutes of Health (GM113602)

  • Wallace F Marshall

Fundacion Ramon Areces

  • Jose-Jesus Fernandez

Spanish AEI/FEDER (SAF2017-84565-R)

  • Jose-Jesus Fernandez

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

Reviewing Editor

  1. Sriram Subramaniam, University of British Columbia, Canada

Publication history

  1. Received: November 6, 2018
  2. Accepted: February 10, 2019
  3. Accepted Manuscript published: February 11, 2019 (version 1)
  4. Version of Record published: February 21, 2019 (version 2)

Copyright

© 2019, Li 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. Sam Li
  2. Jose-Jesus Fernandez
  3. Wallace F Marshall
  4. David A Agard
(2019)
Electron cryo-tomography provides insight into procentriole architecture and assembly mechanism
eLife 8:e43434.
https://doi.org/10.7554/eLife.43434

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