Dynein-2 intermediate chains play crucial but distinct roles in primary cilia formation and function

  1. Laura Vuolo
  2. Nicola L Stevenson
  3. Kate J Heesom
  4. David John Stephens  Is a corresponding author
  1. University of Bristol, United Kingdom

Abstract

The dynein-2 microtubule motor is the retrograde motor for intraflagellar transport. Mutations in dynein-2 components cause skeletal ciliopathies, notably Jeune syndrome. Dynein-2 contains a heterodimer of two non-identical intermediate chains, WDR34 and WDR60. Here, we use knockout cell lines to demonstrate that each intermediate chain has a distinct role in cilium function. Using quantitative proteomics, we show that WDR34 KO cells can assemble a dynein-2 motor complex that binds IFT proteins yet fails to extend an axoneme, indicating complex function is stalled. In contrast, WDR60 KO cells do extend axonemes but show reduced assembly of dynein-2 and binding to IFT proteins. Both proteins are required to maintain a functional transition zone and for efficient bidirectional intraflagellar transport. Our results indicate that the subunit asymmetry within the dynein-2 complex is matched with a functional asymmetry between the dynein-2 intermediate chains. Furthermore, this work reveals that loss of function of dynein-2 leads to defects in transition zone architecture, as well as intraflagellar transport.

Data availability

Proteomics data are included as an Excel file which is readily readable and accessible for the majority of researchers. The mass spectrometry proteomics data have been deposited to the ProteomeXchange Consortium via the PRIDE [1] partner repository with the dataset identifier PXD010398.

The following data sets were generated

Article and author information

Author details

  1. Laura Vuolo

    School of Biochemistry, University of Bristol, Bristol, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-9801-9206
  2. Nicola L Stevenson

    School of Biochemistry, University of Bristol, Bristol, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  3. Kate J Heesom

    Proteomics Facility, Faculty of Biomedical Sciences, University of Bristol, Bristol, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  4. David John Stephens

    School of Biochemistry, University of Bristol, Bristol, United Kingdom
    For correspondence
    david.stephens@bristol.ac.uk
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-5297-3240

Funding

Medical Research Council (MR/P000177/1)

  • Nicola L Stevenson
  • David John Stephens

Biotechnology and Biological Sciences Research Council (BB/N000420/1)

  • Laura Vuolo
  • David John Stephens

Medical Research Council (MR/K018019/1)

  • Nicola L Stevenson
  • David John Stephens

Biotechnology and Biological Sciences Research Council (BB/L014181/1)

  • David John Stephens

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

Reviewing Editor

  1. Andrew P Carter, MRC Laboratory of Molecular Biology, United Kingdom

Publication history

  1. Received: June 28, 2018
  2. Accepted: October 14, 2018
  3. Accepted Manuscript published: October 15, 2018 (version 1)
  4. Accepted Manuscript updated: October 16, 2018 (version 2)
  5. Version of Record published: November 1, 2018 (version 3)

Copyright

© 2018, Vuolo 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. Laura Vuolo
  2. Nicola L Stevenson
  3. Kate J Heesom
  4. David John Stephens
(2018)
Dynein-2 intermediate chains play crucial but distinct roles in primary cilia formation and function
eLife 7:e39655.
https://doi.org/10.7554/eLife.39655

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