A bioactive peptide amidating enzyme is required for ciliogenesis

  1. Dhivya Kumar
  2. Daniela Strenkert
  3. Ramila S Patel-King
  4. Michael T Leonard
  5. Sabeeha S Merchant
  6. Richard E Mains
  7. Stephen M King  Is a corresponding author
  8. Betty A Eipper  Is a corresponding author
  1. University of Connecticut Health Center, United States
  2. University of California Los Angeles, United States
  3. University of California, Los Angeles, United States

Abstract

The pathways controlling cilium biogenesis in different cell types have not been fully elucidated. We recently identified peptidylglycine α-amidating monooxygenase (PAM), an enzyme required for generating amidated bioactive signaling peptides, in Chlamydomonas and mammalian cilia. Here, we show that PAM is required for the normal assembly of motile and primary cilia in Chlamydomonas, planaria and mice. Chlamydomonas PAM knockdown lines failed to assemble cilia beyond the transition zone, had abnormal Golgi architecture and altered levels of cilia assembly components. Decreased PAM gene expression reduced motile ciliary density on the ventral surface of planaria and resulted in the appearance of cytosolic axonemes lacking a ciliary membrane. The architecture of primary cilia on neuroepithelial cells in Pam-/- mouse embryos was also aberrant. Our data suggest that PAM activity and alterations in post-Golgi trafficking contribute to the observed ciliogenesis defects and provide an unanticipated, highly conserved, link between PAM, amidation and ciliary assembly.

Article and author information

Author details

  1. Dhivya Kumar

    Department of Molecular Biology and Biophysics, University of Connecticut Health Center, Farmington, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-3737-014X
  2. Daniela Strenkert

    Department of Chemistry and Biochemistry, University of California Los Angeles, Los Angeles, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Ramila S Patel-King

    Department of Molecular Biology and Biophysics, University of Connecticut Health Center, Farmington, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Michael T Leonard

    Department of Chemistry and Biochemistry, University of California Los Angeles, Los Angeles, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Sabeeha S Merchant

    Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, United States
    Competing interests
    The authors declare that no competing interests exist.
  6. Richard E Mains

    Department of Neuroscience, University of Connecticut Health Center, Farmington, United States
    Competing interests
    The authors declare that no competing interests exist.
  7. Stephen M King

    Department of Molecular Biology and Biophysics, University of Connecticut Health Center, Farmington, United States
    For correspondence
    king@uchc.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-5484-5530
  8. Betty A Eipper

    Department of Neuroscience, University of Connecticut Health Center, Farmington, United States
    For correspondence
    eipper@uchc.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-1171-5557

Funding

National Institutes of Health (DK032949)

  • Betty A Eipper

National Institutes of Health (GM051293)

  • Stephen M King

National Institutes of Health (GM042143)

  • Sabeeha S Merchant

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

Ethics

Animal experimentation: All procedures involving mice were approved by the UCHC Institutional Animal Care and Use Committee (protocol 101529-1119), in accordance with National Institutes of Health and ARRIVE guidelines (https://www. nc3rs.org.uk/arrive-guidelines).

Reviewing Editor

  1. Anna Akhmanova, Utrecht University, Netherlands

Publication history

  1. Received: February 3, 2017
  2. Accepted: May 15, 2017
  3. Accepted Manuscript published: May 17, 2017 (version 1)
  4. Version of Record published: June 6, 2017 (version 2)
  5. Version of Record updated: June 16, 2017 (version 3)

Copyright

© 2017, Kumar 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. Dhivya Kumar
  2. Daniela Strenkert
  3. Ramila S Patel-King
  4. Michael T Leonard
  5. Sabeeha S Merchant
  6. Richard E Mains
  7. Stephen M King
  8. Betty A Eipper
(2017)
A bioactive peptide amidating enzyme is required for ciliogenesis
eLife 6:e25728.
https://doi.org/10.7554/eLife.25728

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