1. Developmental Biology
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Patched1 and Patched2 inhibit Smoothened non-cell autonomously

  1. Brock Roberts
  2. Catalina Casillas
  3. Astrid C Alfaro
  4. Carina Jägers
  5. Henk Roelink  Is a corresponding author
  1. University of California, Berkeley, United States
Research Article
  • Cited 15
  • Views 1,908
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Cite this article as: eLife 2016;5:e17634 doi: 10.7554/eLife.17634

Abstract

Smoothened (Smo) inhibition by Patched (Ptch) is central to Hedgehog (Hh) signaling. Ptch, a proton driven antiporter, is required for Smo inhibition via an unknown mechanism. Hh ligand binding to Ptch reverses this inhibition and activated Smo initiates the Hh response. To determine whether Ptch inhibits Smo strictly in the same cell or also mediates non cell-autonomous Smo inhibition, we generated genetically mosaic neuralized embryoid bodies (nEBs) from mouse embryonic stem cells (mESCs). These experiments utilized novel mESC lines in which Ptch1, Ptch2, Smo, Shh and 7dhcr were inactivated via gene editing in multiple combinations, allowing us to measure non-cell autonomous interactions between cells with differing Ptch1/2 status. In several independent assays the Hh response was repressed by Ptch1/2 in nearby cells. When 7dhcr was targeted cells displayed elevated non-cell autonomous inhibition. These findings support a model in which Ptch1/2 mediate secretion of a Smo-inhibitory cholesterol precursor.

Article and author information

Author details

  1. Brock Roberts

    Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Catalina Casillas

    Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Astrid C Alfaro

    Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Carina Jägers

    Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Henk Roelink

    Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    For correspondence
    roelink@berkeley.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-5260-3634

Funding

National Institute of General Medical Sciences (R01GM097035)

  • Henk Roelink

California Institute of Regenerative Medicine (TG2-01164)

  • Brock Roberts

National Institute of General Medical Sciences (1R01GM117090)

  • Henk Roelink

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

Reviewing Editor

  1. Marianne E Bronner, California Institute of Technology, United States

Publication history

  1. Received: May 10, 2016
  2. Accepted: August 22, 2016
  3. Accepted Manuscript published: August 23, 2016 (version 1)
  4. Version of Record published: September 7, 2016 (version 2)

Copyright

© 2016, Roberts 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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