1. Structural Biology and Molecular Biophysics
  2. Cell Biology
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CatSperζ regulates the structural continuity of sperm Ca2+ signaling domains and is required for normal fertility

  1. Jean-Ju Chung  Is a corresponding author
  2. Kiyoshi Miki
  3. Doory Kim
  4. Sang-Hee Shim
  5. Huanan F Shi
  6. Jae Yeon Hwang
  7. Xinjiang Cai
  8. Yusuf Iseri
  9. Xiaowei Zhuang
  10. David E Clapham  Is a corresponding author
  1. Yale School of Medicine, United States
  2. Howard Hughes Medical Institute, Boston Children's Hospital, United States
  3. Howard Hughes Medical Institute, Harvard University, United States
  4. Ichan School of Medicine at Mount Sinai, United States
Research Article
  • Cited 78
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Cite this article as: eLife 2017;6:e23082 doi: 10.7554/eLife.23082

Abstract

We report that the Gm7068 (CatSperε) and Tex40 (CatSperζ) genes encode novel subunits of a 9-subunit CatSper ion channel complex. Targeted disruption of CatSperζ reduces CatSper current and sperm rheotactic efficiency in mice, resulting in severe male subfertility. Normally distributed in linear quadrilateral nanodomains along the flagellum, the complex lacking CatSperζ is disrupted at ~0.8 μm intervals along the flagellum. This disruption renders the proximal flagellum inflexible and alters the 3D flagellar envelope, thus preventing sperm from reorienting against fluid flow in vitro and efficiently migrating in vivo. Ejaculated CatSperζ-null sperm cells retrieved from the mated female uterus partially rescue in vitro fertilization (IVF) that failed with epididymal spermatozoa alone. Human CatSperε is quadrilaterally arranged along the flagella, similar to the CatSper complex in mouse sperm. We speculate that the newly identified CatSperζ subunit is a late evolutionary adaptation to maximize fertilization inside the mammalian female reproductive tract.

Article and author information

Author details

  1. Jean-Ju Chung

    Department of Cellular and Molecular Physiology, Yale School of Medicine, New Haven, United States
    For correspondence
    jean-ju.chung@yale.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-8018-1355

  2. Kiyoshi Miki

    Howard Hughes Medical Institute, Boston Children's Hospital, Boston, United States
    Competing interests
    The authors declare that no competing interests exist.

  3. Doory Kim

    Department of Chemistry and Chemical Biology, Howard Hughes Medical Institute, Harvard University, Cambridge, United States
    Competing interests
    The authors declare that no competing interests exist.

  4. Sang-Hee Shim

    Department of Chemistry and Chemical Biology, Howard Hughes Medical Institute, Harvard University, Cambridge, United States
    Competing interests
    The authors declare that no competing interests exist.

  5. Huanan F Shi

    Department of Cellular and Molecular Physiology, Yale School of Medicine, New Haven, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-3710-5917

  6. Jae Yeon Hwang

    Department of Cellular and Molecular Physiology, Yale School of Medicine, New Haven, United States
    Competing interests
    The authors declare that no competing interests exist.

  7. Xinjiang Cai

    Department of Medicine, Ichan School of Medicine at Mount Sinai, New York, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-8933-7133

  8. Yusuf Iseri

    Howard Hughes Medical Institute, Boston Children's Hospital, Boston, United States
    Competing interests
    The authors declare that no competing interests exist.

  9. Xiaowei Zhuang

    Department of Chemistry and Chemical Biology, Howard Hughes Medical Institute, Harvard University, Cambridge, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-6034-7853

  10. David E Clapham

    Howard Hughes Medical Institute, Boston Children's Hospital, Boston, United States
    For correspondence
    dclapham@enders.tch.harvard.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-4459-9428

Funding

Howard Hughes Medical Institute

  • Xiaowei Zhuang
  • David E Clapham

Yale School of Medicine (Goodman-Gilman Yale Scholar Award 2015-08)

  • Jean-Ju Chung

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

Ethics

Animal experimentation: This study was performed in strict accordance with the recommendations in the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health. All the mice were treated in accordance with guidelines approved by the Boston Children's Hospital (13-01-2341R) and Yale (2015-20079) Animal Care and Use Committees (IACUC).

Reviewing Editor

  1. Kenton J Swartz, National Institutes of Health, United States

Publication history

  1. Received: November 8, 2016
  2. Accepted: February 20, 2017
  3. Accepted Manuscript published: February 22, 2017 (version 1)
  4. Accepted Manuscript updated: February 23, 2017 (version 2)
  5. Version of Record published: March 22, 2017 (version 3)

Copyright

© 2017, Chung 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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