Comparative genetic screens in human cells reveal new regulatory mechanisms in WNT signaling

  1. Andres M Lebensohn
  2. Ramin Dubey
  3. Leif R Neitzel
  4. Ofelia Tacchelly-Benites
  5. Eungi Yang
  6. Caleb D Marceau
  7. Eric M Davis
  8. Bhaven B Patel
  9. Zahra Bahrami-Nejad
  10. Kyle J Travaglini
  11. Yashi Ahmed
  12. Ethan Lee
  13. Jan E Carette  Is a corresponding author
  14. Rajat Rohatgi  Is a corresponding author
  1. Stanford University School of Medicine, United States
  2. Vanderbilt University Medical Center, United States
  3. Geisel School of Medicine at Dartmouth College, United States
  4. University of Colorado, Boulder, United States

Abstract

The comprehensive understanding of cellular signaling pathways remains a challenge due to multiple layers of regulation that may become evident only when the pathway is probed at different levels or critical nodes are eliminated. To discover regulatory mechanisms in canonical WNT signaling, we conducted a systematic forward genetic analysis through reporter-based screens in haploid human cells. Comparison of screens for negative, sensitizing and positive regulators of WNT signaling, mediators of R-spondin-dependent signaling and suppressors of constitutive signaling induced by loss of the tumor suppressor APC or casein kinase 1α uncovered new regulatory features at many levels of the pathway. These include a requirement for the transcription factor TFAP4, a role for the DAX domain of AXIN2 in controlling β-catenin activity, a contribution of GPI anchor biosynthetic enzymes and glypicans to R-spondin-potentiated signaling, and two different mechanisms that regulate signaling when distinct components of the β-catenin destruction complex are lost.

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The following data sets were generated

Article and author information

Author details

  1. Andres M Lebensohn

    Department of Biochemistry, Stanford University School of Medicine, Stanford, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Ramin Dubey

    Department of Biochemistry, Stanford University School of Medicine, Stanford, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Leif R Neitzel

    Department of Cell and Developmental Biology, Vanderbilt University Medical Center, Nashville, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Ofelia Tacchelly-Benites

    Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth College, Hanover, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Eungi Yang

    Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth College, Hanover, United States
    Competing interests
    The authors declare that no competing interests exist.
  6. Caleb D Marceau

    Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, United States
    Competing interests
    The authors declare that no competing interests exist.
  7. Eric M Davis

    Department of Molecular, Cellular, and Developmental Biology, University of Colorado, Boulder, Boulder, United States
    Competing interests
    The authors declare that no competing interests exist.
  8. Bhaven B Patel

    Department of Biochemistry, Stanford University School of Medicine, Stanford, United States
    Competing interests
    The authors declare that no competing interests exist.
  9. Zahra Bahrami-Nejad

    Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, United States
    Competing interests
    The authors declare that no competing interests exist.
  10. Kyle J Travaglini

    Department of Biochemistry, Stanford University School of Medicine, Stanford, United States
    Competing interests
    The authors declare that no competing interests exist.
  11. Yashi Ahmed

    Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth College, Hanover, United States
    Competing interests
    The authors declare that no competing interests exist.
  12. Ethan Lee

    Department of Cell and Developmental Biology, Vanderbilt University Medical Center, Nashville, United States
    Competing interests
    The authors declare that no competing interests exist.
  13. Jan E Carette

    Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, United States
    For correspondence
    carette@stanford.edu
    Competing interests
    The authors declare that no competing interests exist.
  14. Rajat Rohatgi

    Department of Biochemistry, Stanford University School of Medicine, Stanford, United States
    For correspondence
    rrohatgi@stanford.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-7609-8858

Funding

National Institutes of Health (DP2 AI104557,DP2 GM105448,R01 GM081635,R01 GM103926,RO1 CA105038)

  • Yashi Ahmed
  • Ethan Lee
  • Jan E Carette
  • Rajat Rohatgi

National Science Foundation (DBI-1039423)

  • Yashi Ahmed

David and Lucile Packard Foundation (Fellow Award)

  • Jan E Carette

Helen Hay Whitney Foundation (Novartis Fellowship)

  • Andres M Lebensohn

Stanford University School of Medicine (Josephine Q. Berry Fellowship)

  • Rajat Rohatgi

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

Reviewing Editor

  1. Utpal Banerjee, University of California, Los Angeles, United States

Publication history

  1. Received: September 13, 2016
  2. Accepted: December 7, 2016
  3. Accepted Manuscript published: December 20, 2016 (version 1)
  4. Accepted Manuscript updated: December 22, 2016 (version 2)
  5. Version of Record published: January 23, 2017 (version 3)
  6. Version of Record updated: February 1, 2017 (version 4)

Copyright

© 2016, Lebensohn 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. Andres M Lebensohn
  2. Ramin Dubey
  3. Leif R Neitzel
  4. Ofelia Tacchelly-Benites
  5. Eungi Yang
  6. Caleb D Marceau
  7. Eric M Davis
  8. Bhaven B Patel
  9. Zahra Bahrami-Nejad
  10. Kyle J Travaglini
  11. Yashi Ahmed
  12. Ethan Lee
  13. Jan E Carette
  14. Rajat Rohatgi
(2016)
Comparative genetic screens in human cells reveal new regulatory mechanisms in WNT signaling
eLife 5:e21459.
https://doi.org/10.7554/eLife.21459
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