1. Cell Biology
  2. Neuroscience
Download icon

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
Research Article
  • Cited 17
  • Views 1,464
  • Annotations
Cite this article as: eLife 2016;5:e18312 doi: 10.7554/eLife.18312

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.

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 8, 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.

Metrics

  • 1,464
    Page views
  • 416
    Downloads
  • 17
    Citations

Article citation count generated by polling the highest count across the following sources: Scopus, Crossref, PubMed Central.

Download links

A two-part list of links to download the article, or parts of the article, in various formats.

Downloads (link to download the article as PDF)

Download citations (links to download the citations from this article in formats compatible with various reference manager tools)

Open citations (links to open the citations from this article in various online reference manager services)

Further reading

    1. Biochemistry and Chemical Biology
    2. Cell Biology
    Haibin Yang et al.
    Research Article Updated

    Communications between actin filaments and integrin-mediated focal adhesion (FA) are crucial for cell adhesion and migration. As a core platform to organize FA proteins, the tripartite ILK/PINCH/Parvin (IPP) complex interacts with actin filaments to regulate the cytoskeleton-FA crosstalk. Rsu1, a Ras suppressor, is enriched in FA through PINCH1 and plays important roles in regulating F-actin structures. Here, we solved crystal structures of the Rsu1/PINCH1 complex, in which the leucine-rich-repeats of Rsu1 form a solenoid structure to tightly associate with the C-terminal region of PINCH1. Further structural analysis uncovered that the interaction between Rsu1 and PINCH1 blocks the IPP-mediated F-actin bundling by disrupting the binding of PINCH1 to actin. Consistently, overexpressing Rsu1 in HeLa cells impairs stress fiber formation and cell spreading. Together, our findings demonstrated that Rsu1 is critical for tuning the communication between F-actin and FA by interacting with the IPP complex and negatively modulating the F-actin bundling.

    1. Cell Biology
    2. Chromosomes and Gene Expression
    Qiuying Liu et al.
    Research Article Updated

    The regulation of stem cell fate is poorly understood. Genetic studies in Caenorhabditis elegans lead to the hypothesis that a conserved cytoplasmic double-negative feedback loop consisting of the RNA-binding protein Trim71 and the let-7 microRNA controls the pluripotency and differentiation of stem cells. Although let-7-microRNA-mediated inhibition of Trim71 promotes differentiation, whether and how Trim71 regulates pluripotency and inhibits the let-7 microRNA are still unknown. Here, we show that Trim71 represses Ago2 mRNA translation in mouse embryonic stem cells. Blocking this repression leads to a specific post-transcriptional increase of mature let-7 microRNAs, resulting in let-7-dependent stemness defects and accelerated differentiation in the stem cells. These results not only support the Trim71-let-7-microRNA bi-stable switch model in controlling stem cell fate, but also reveal that repressing the conserved pro-differentiation let-7 microRNAs at the mature microRNA level by Ago2 availability is critical to maintaining pluripotency.