PDZD7-MYO7A complex identified in enriched stereocilia membranes

  1. Clive P Morgan
  2. Jocelyn F Krey
  3. M'Hamed Grati
  4. Bo Zhao
  5. Shannon Fallen
  6. Abhiraami Kannan-Sundhari
  7. Xue Zhong Liu
  8. Dongseok Choi
  9. Ulrich Müller
  10. Peter G Barr-Gillespie  Is a corresponding author
  1. Oregon Health and Science University, United States
  2. University of Miami, United States
  3. The Scripps Research Institute, United States

Abstract

While more than 70 genes have been linked to deafness, most of which are expressed in mechanosensory hair cells of the inner ear, a challenge has been to link these genes into molecular pathways. One example is Myo7a (myosin VIIA), in which deafness mutations affect the development and function of the mechanically sensitive stereocilia of hair cells. We describe here a procedure for the isolation of low-abundance protein complexes from stereocilia membrane fractions. Using this procedure, combined with identification and quantitation of proteins with mass spectrometry, we demonstrate that MYO7A forms a complex with PDZD7, a paralog of USH1C and DFNB31. MYO7A and PDZD7 interact in tissue-culture cells, and co-localize to the ankle-link region of stereocilia in wild-type but not Myo7a mutant mice. Our data thus describe a new paradigm for the interrogation of low-abundance protein complexes in hair cell stereocilia and establish an unanticipated link between MYO7A and PDZD7.

Data availability

The following data sets were generated
    1. Barr-Gillespie
    2. PG
    (2016) D10 Stereocilia Membrane Enrichment
    Available at the PRIDE Archive (accession no. PXD004222).

Article and author information

Author details

  1. Clive P Morgan

    Oregon Hearing Research Center, Oregon Health and Science University, Portland, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Jocelyn F Krey

    Oregon Hearing Research Center, Oregon Health and Science University, Portland, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. M'Hamed Grati

    Department of Otolaryngology, Miller School of Medicine, University of Miami, Miami, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Bo Zhao

    Dorris Neuroscience Center, The Scripps Research Institute, La Jolla, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Shannon Fallen

    Oregon Hearing Research Center, Oregon Health and Science University, Portland, United States
    Competing interests
    The authors declare that no competing interests exist.
  6. Abhiraami Kannan-Sundhari

    Department of Otolaryngology, Miller School of Medicine,, University of Miami, Miami, United States
    Competing interests
    The authors declare that no competing interests exist.
  7. Xue Zhong Liu

    Department of Otolaryngology, Miller School of Medicine,, University of Miami, Miami, United States
    Competing interests
    The authors declare that no competing interests exist.
  8. Dongseok Choi

    OHSU-PSU School of Public Health, Oregon Health and Science University, Portland, United States
    Competing interests
    The authors declare that no competing interests exist.
  9. Ulrich Müller

    Dorris Neuroscience Center, The Scripps Research Institute, La Jolla, United States
    Competing interests
    The authors declare that no competing interests exist.
  10. Peter G Barr-Gillespie

    Oregon Hearing Research Center, Oregon Health and Science University, Portland, United States
    For correspondence
    gillespp@ohsu.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-9787-5860

Funding

National Institute on Deafness and Other Communication Disorders (R01DC002368)

  • Peter G Barr-Gillespie

National Institute on Deafness and Other Communication Disorders (P30DC005983)

  • Peter G Barr-Gillespie

National Institute on Deafness and Other Communication Disorders (R01DC014427)

  • Ulrich Müller
  • Peter G Barr-Gillespie

National Institute on Deafness and Other Communication Disorders (R01DC005965)

  • Ulrich Müller

National Institute on Deafness and Other Communication Disorders (R01DC05575)

  • Xue Zhong Liu

National Institute on Deafness and Other Communication Disorders (R01DC012546)

  • Xue Zhong Liu

National Institute on Deafness and Other Communication Disorders (R01DC012115)

  • Xue Zhong Liu

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 of the animals were handled and euthanized according to a protocol (#IS00003292) that was approved by the institutional animal care and use committee (IACUC) of the Oregon Health & Science University.

Reviewing Editor

  1. Jeremy Nathans, Johns Hopkins University School of Medicine, United States

Publication history

  1. Received: June 24, 2016
  2. Accepted: August 14, 2016
  3. Accepted Manuscript published: August 15, 2016 (version 1)
  4. Version of Record published: August 30, 2016 (version 2)

Copyright

© 2016, Morgan 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. Clive P Morgan
  2. Jocelyn F Krey
  3. M'Hamed Grati
  4. Bo Zhao
  5. Shannon Fallen
  6. Abhiraami Kannan-Sundhari
  7. Xue Zhong Liu
  8. Dongseok Choi
  9. Ulrich Müller
  10. Peter G Barr-Gillespie
(2016)
PDZD7-MYO7A complex identified in enriched stereocilia membranes
eLife 5:e18312.
https://doi.org/10.7554/eLife.18312

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