PDZD7-MYO7A complex identified in enriched stereocilia membranes
- Oregon Health and Science University, United States
- University of Miami, United States
- 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
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D10 Stereocilia Membrane EnrichmentAvailable at the PRIDE Archive (accession no. PXD004222).
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Myosin VIIA 138-1 immunoaffinity purificationAvailable at the PRIDE Archive (accession no. PXD004221).
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HEK cell MYO7A-PDZD7 immunoprecipitationAvailable at the PRIDE Archive (accession no. PXD004266).
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MYO7A PDZD7 complexPublicly accessible at panoramaweb.org.
Article and author information
Author details
Peter G Barr-Gillespie
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.
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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PDZD7-MYO7A complex identified in enriched stereocilia membranes
eLife 5:e18312.
https://doi.org/10.7554/eLife.18312
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