Pak1 and PP2A antagonize aPKC function to support cortical tension induced by the Crumbs-Yurt complex

  1. Cornelia Biehler
  2. Katheryn E Rothenberg
  3. Alexandra Jette
  4. Helori-Mael Gaude
  5. Rodrigo Fernandez-Gonzalez
  6. Patrick Laprise  Is a corresponding author
  1. Universite Laval, Canada
  2. University of Toronto, Canada
  3. Université Laval, Canada

Abstract

The Drosophila polarity protein Crumbs is essential for the establishment and growth of the apical domain in epithelial cells. The protein Yurt limits the ability of Crumbs to promote apical membrane growth, thereby defining proper apical/lateral membrane ratio that is crucial for forming and maintaining complex epithelial structures such as tubes or acini. Here, we show that Yurt also increases Myosin-dependent cortical tension downstream of Crumbs. Yurt overexpression thus induces apical constriction in epithelial cells. The kinase aPKC phosphorylates Yurt, thereby dislodging the latter from the apical domain and releasing apical tension. In contrast, the kinase Pak1 promotes Yurt dephosphorylation through activation of the phosphatase PP2A. The Pak1-PP2A module thus opposes aPKC function and supports Yurt-induced apical constriction. Hence, the complex interplay between Yurt, aPKC, Pak1 and PP2A contributes to the functional plasticity of Crumbs. Overall, our data increase our understanding of how proteins sustaining epithelial cell polarization and Myosin-dependent cell contractility interact with one another to control epithelial tissue architecture.

Data availability

Source data have been provided for all figures and are available as supporting files.

Article and author information

Author details

  1. Cornelia Biehler

    BMBMP, Universite Laval, Quebec, Canada
    Competing interests
    The authors declare that no competing interests exist.
  2. Katheryn E Rothenberg

    CSB, University of Toronto, Toronto, Canada
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-8191-7528
  3. Alexandra Jette

    BMBMP, Universite Laval, Wuebec, Canada
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-5423-2374
  4. Helori-Mael Gaude

    BMBMP, Universite Laval, Quebec, Canada
    Competing interests
    The authors declare that no competing interests exist.
  5. Rodrigo Fernandez-Gonzalez

    Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Canada
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-0770-744X
  6. Patrick Laprise

    BMBMP, Université Laval, Quebec, Canada
    For correspondence
    Patrick.Laprise@crchudequebec.ulaval.ca
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-9785-4376

Funding

Canadian Institutes of Health Research (Operating grant,MOP-142236)

  • Patrick Laprise

Canadian Institutes of Health Research (Operating grant,MOP-156279)

  • Rodrigo Fernandez-Gonzalez

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

Reviewing Editor

  1. Michel Bagnat, Duke University, United States

Version history

  1. Received: March 2, 2021
  2. Accepted: June 30, 2021
  3. Accepted Manuscript published: July 2, 2021 (version 1)
  4. Version of Record published: July 15, 2021 (version 2)

Copyright

© 2021, Biehler 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. Cornelia Biehler
  2. Katheryn E Rothenberg
  3. Alexandra Jette
  4. Helori-Mael Gaude
  5. Rodrigo Fernandez-Gonzalez
  6. Patrick Laprise
(2021)
Pak1 and PP2A antagonize aPKC function to support cortical tension induced by the Crumbs-Yurt complex
eLife 10:e67999.
https://doi.org/10.7554/eLife.67999

Share this article

https://doi.org/10.7554/eLife.67999

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