1. Cell Biology
  2. Structural Biology and Molecular Biophysics

Calaxin stabilizes the docking of outer arm dyneins onto ciliary doublet microtubule in vertebrates

  1. Hiroshi Yamaguchi
  2. Motohiro Morikawa
  3. Masahide Kikkawa  Is a corresponding author
  1. University of Tokyo, Japan
https://doi.org/10.7554/eLife.84860
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  1. Hiroshi Yamaguchi
  2. Motohiro Morikawa
  3. Masahide Kikkawa
(2023)
Calaxin stabilizes the docking of outer arm dyneins onto ciliary doublet microtubule in vertebrates
eLife 12:e84860.
https://doi.org/10.7554/eLife.84860
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Abstract

Outer arm dynein (OAD) is the main force generator of ciliary beating. Although OAD loss is the most frequent cause of human primary ciliary dyskinesia, the docking mechanism of OAD onto the ciliary doublet microtubule (DMT) remains elusive in vertebrates. Here, we analyzed the functions of Calaxin/Efcab1 and Armc4, the two of five components of vertebrate OAD-DC (docking complex), using zebrafish spermatozoa and cryo-electron tomography. Mutation of armc4 caused complete loss of OAD, whereas mutation of calaxin caused only partial loss of OAD. Detailed structural analysis revealed that calaxin-/- OADs are tethered to DMT through DC components other than Calaxin, and that recombinant Calaxin can autonomously rescue the deficient DC structure and the OAD instability. Our data demonstrate the discrete roles of Calaxin and Armc4 in the OAD-DMT interaction, suggesting the stabilizing process of OAD docking onto DMT in vertebrates.

Data availability

The Source Data files contain the numerical data and raw gel images used to generate the figures.The maps generated in this study have been deposited in EMDB under the following accession numbers: EMD-34791, EMD-34792, EMD-34793, EMD-34794, EMD-34795, EMD-34796, EMD-34797, EMD-34798, EMD-34799, EMD-34800, EMD-34801, and EMD-34802.

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Author details

  1. Hiroshi Yamaguchi

    Department of Cell Biology and Anatomy, University of Tokyo, Tokyo, Japan
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-8722-129X

  2. Motohiro Morikawa

    Department of Cell Biology and Anatomy, University of Tokyo, Tokyo, Japan
    Competing interests
    The authors declare that no competing interests exist.

  3. Masahide Kikkawa

    Department of Cell Biology and Department of Cell Biology and Anatomy, Graduate School of Medicine, University of Tokyo, Tokyo, Japan
    For correspondence
    mkikkawa@m.u-tokyo.ac.jp
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-7656-8194

Funding

Japan Society for the Promotion of Science (KAKENHI Grant Number 16H02502)

  • Masahide Kikkawa

Japan Society for the Promotion of Science (KAKENHI Grant Number 21H04762)

  • Masahide Kikkawa

Japan Agency for Medical Research and Development (Grant Number JP22ama121002j001)

  • Masahide Kikkawa

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

Copyright

© 2023, Yamaguchi 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. Hiroshi Yamaguchi
  2. Motohiro Morikawa
  3. Masahide Kikkawa
(2023)
Calaxin stabilizes the docking of outer arm dyneins onto ciliary doublet microtubule in vertebrates
eLife 12:e84860.
https://doi.org/10.7554/eLife.84860

Share this article

https://doi.org/10.7554/eLife.84860

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