DNA-damage induced cell death in yap1;wwtr1 mutant epidermal basal cells

  1. Jason KH Lai  Is a corresponding author
  2. Pearlyn JY Toh
  3. Hamizah A Cognart
  4. Geetika Chouhan
  5. Timothy E Saunders  Is a corresponding author
  1. National University of Singapore, Singapore
  2. Tata Institute of Fundamental Research, India

Abstract

In a previous study, it was reported that Yap1 and Wwtr1 in zebrafish regulates the morphogenesis of the posterior body and epidermal fin fold (Kimelman, D., et al. 2017). We report here that DNA damage induces apoptosis of epidermal basal cells (EBCs) in zebrafish yap1-/-;wwtr1-/- embryos. Specifically, these mutant EBCs exhibit active Caspase-3, Caspase-8 and γH2AX, consistent with DNA damage serving as a stimulus of the extrinsic apoptotic pathway in epidermal cells. Live imaging of zebrafish epidermal cells reveals a steady growth of basal cell size in the developing embryo, but this growth is inhibited in mutant basal cells followed by apoptosis, leading to the hypothesis that factors underscoring cell size play a role in this DNA damage-induced apoptosis phenotype. We tested two of these factors using cell stretching and substrate stiffness assays, and found that HaCaT cells cultured on stiff substrates exhibit more numerous γH2AX foci compared to ones cultured on soft substrates. Thus, our experiments suggest that substrate rigidity may modulate genomic stress in epidermal cells, and that Yap1 and Wwtr1 promotes their survival.

Data availability

All data generated or analysed during this study are included in the manuscript and supporting file; Source Data files have been provided for Figures 1, 3, 4, 5 and 6.

Article and author information

Author details

  1. Jason KH Lai

    National University of Singapore, Singapore, Singapore
    For correspondence
    jasonlaikh@gmail.com
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-3476-4733
  2. Pearlyn JY Toh

    National University of Singapore, Singapore, Singapore
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-0907-7947
  3. Hamizah A Cognart

    National University of Singapore, Singapore, Singapore
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-3090-1526
  4. Geetika Chouhan

    Department of Biological Sciences, Tata Institute of Fundamental Research, Mumbai, India
    Competing interests
    The authors declare that no competing interests exist.
  5. Timothy E Saunders

    National University of Singapore, Singapore, Singapore
    For correspondence
    timothy.saunders@warwick.ac.uk
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-5755-0060

Funding

Ministry of Education - Singapore (MOE2016-T3-1-002)

  • Jason KH Lai
  • Pearlyn JY Toh
  • Hamizah A Cognart
  • Timothy E Saunders

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

Ethics

Animal experimentation: All zebrafish husbandry was performed under standard conditions in accordance with institutional (Biological Resource Center, A*Star, Singapore, and Tata Institute of Fundamental Research, India) and national ethical and animal welfare guidelines (Singapore IACUC: 181323 and GMAC: Res-21-034). All users were trained in ethical handling of zebrafish.

Copyright

© 2022, Lai 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. Jason KH Lai
  2. Pearlyn JY Toh
  3. Hamizah A Cognart
  4. Geetika Chouhan
  5. Timothy E Saunders
(2022)
DNA-damage induced cell death in yap1;wwtr1 mutant epidermal basal cells
eLife 11:e72302.
https://doi.org/10.7554/eLife.72302

Share this article

https://doi.org/10.7554/eLife.72302

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