1. Cell Biology

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
https://doi.org/10.7554/eLife.43434
Share this article
Cite this article
  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
  2. Download BibTeX
  3. Download .RIS

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

The following data sets were generated

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

Version 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.

Metrics

  • 4,587
    views
  • 547
    downloads
  • 30
    citations

Views, downloads and citations are aggregated across all versions of this paper published by eLife.

Download links

A two-part list of links to download the article, or parts of the article, in various formats.

Downloads (link to download the article as PDF)

Open citations (links to open the citations from this article in various online reference manager services)

Cite this article (links to download the citations from this article in formats compatible with various reference manager tools)

  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

Share this article

https://doi.org/10.7554/eLife.43434

Categories and tags

Research organism

Further reading

    1. Cell Biology

    Mecp2 fine-tunes quiescence exit by targeting nuclear receptors

    Jun Yang, Shitian Zou ... Xiaochun Bai
    Research Article

    Quiescence (G0) maintenance and exit are crucial for tissue homeostasis and regeneration in mammals. Here, we show that methyl-CpG binding protein 2 (Mecp2) expression is cell cycle-dependent and negatively regulates quiescence exit in cultured cells and in an injury-induced liver regeneration mouse model. Specifically, acute reduction of Mecp2 is required for efficient quiescence exit as deletion of Mecp2 accelerates, while overexpression of Mecp2 delays quiescence exit, and forced expression of Mecp2 after Mecp2 conditional knockout rescues cell cycle reentry. The E3 ligase Nedd4 mediates the ubiquitination and degradation of Mecp2, and thus facilitates quiescence exit. A genome-wide study uncovered the dual role of Mecp2 in preventing quiescence exit by transcriptionally activating metabolic genes while repressing proliferation-associated genes. Particularly disruption of two nuclear receptors, Rara or Nr1h3, accelerates quiescence exit, mimicking the Mecp2 depletion phenotype. Our studies unravel a previously unrecognized role for Mecp2 as an essential regulator of quiescence exit and tissue regeneration.

    1. Cancer Biology
    2. Cell Biology

    Exosomes: How tumors escape the immune system

    Stefanie Schmieder
    Insight

    Mutations in the gene for β-catenin cause liver cancer cells to release fewer exosomes, which reduces the number of immune cells infiltrating the tumor.

    1. Cell Biology
    2. Neuroscience

    Unraveling the link between neuropathy target esterase NTE/SWS, lysosomal storage diseases, inflammation, abnormal fatty acid metabolism, and leaky brain barrier

    Mariana I Tsap, Andriy S Yatsenko ... Halyna R Shcherbata
    Research Article Updated

    Mutations in Drosophila Swiss cheese (SWS) gene or its vertebrate orthologue neuropathy target esterase (NTE) lead to progressive neuronal degeneration in flies and humans. Despite its enzymatic function as a phospholipase is well established, the molecular mechanism responsible for maintaining nervous system integrity remains unclear. In this study, we found that NTE/SWS is present in surface glia that forms the blood-brain barrier (BBB) and that NTE/SWS is important to maintain its structure and permeability. Importantly, BBB glia-specific expression of Drosophila NTE/SWS or human NTE in the sws mutant background fully rescues surface glial organization and partially restores BBB integrity, suggesting a conserved function of NTE/SWS. Interestingly, sws mutant glia showed abnormal organization of plasma membrane domains and tight junction rafts accompanied by the accumulation of lipid droplets, lysosomes, and multilamellar bodies. Since the observed cellular phenotypes closely resemble the characteristics described in a group of metabolic disorders known as lysosomal storage diseases (LSDs), our data established a novel connection between NTE/SWS and these conditions. We found that mutants with defective BBB exhibit elevated levels of fatty acids, which are precursors of eicosanoids and are involved in the inflammatory response. Also, as a consequence of a permeable BBB, several innate immunity factors are upregulated in an age-dependent manner, while BBB glia-specific expression of NTE/SWS normalizes inflammatory response. Treatment with anti-inflammatory agents prevents the abnormal architecture of the BBB, suggesting that inflammation contributes to the maintenance of a healthy brain barrier. Considering the link between a malfunctioning BBB and various neurodegenerative diseases, gaining a deeper understanding of the molecular mechanisms causing inflammation due to a defective BBB could help to promote the use of anti-inflammatory therapies for age-related neurodegeneration.