Eya2 promotes cell cycle progression by regulating DNA damage response during vertebrate limb regeneration
- Harvard University, United States
- Brigham & Women's Hospital, United States
- Tufts University, United States
- Harvard Medical School, United States
Abstract
How salamanders accomplish progenitor cell proliferation while faithfully maintaining genomic integrity and regenerative potential remains elusive. Here we found an innate DNA damage response mechanism that is evident during blastema proliferation (early- to late-bud) and studied its role during tissue regeneration by ablating the function of one of its components, Eyes absent 2. In eya2 mutant axolotls, we found that DNA damage signaling through the H2AX histone variant was deregulated, especially within the proliferating progenitors during limb regeneration. Ultimately, cell cycle progression was impaired at the G1/S and G2/M transitions and regeneration rate was reduced. Similar data were acquired using acute pharmacological inhibition of the Eya2 phosphatase activity and the DNA damage checkpoint kinases Chk1 and Chk2 in wild-type axolotls. Together, our data indicate that highly-regenerative animals employ a robust DNA damage response pathway which involves regulation of H2AX phosphorylation via Eya2 to facilitate proper cell cycle progression upon injury.
Data availability
Raw data can be accessed in the NIH Sequence Read Archive: SUB6297224.
Article and author information
Author details
Funding
Sara Elizabeth O'Brien Trust (Postdoctoral fellowship)
- Konstantinos Sousounis
National Institutes of Health (K99EY029361)
- Konstantinos Sousounis
Paul G. Allen Family Foundation (Allen Discovery Center at Tufts)
- Michael Levin
- Jessica L Whited
National Institutes of Health (1DP2HD087953)
- Jessica L Whited
National Institutes of Health (1R01HD095494)
- Jessica L Whited
Harvard Stem Cell Institute (HIP)
- Jose Martinez Fernandez
Howard Hughes Medical Institute (Gilliam Fellowship)
- Donald M Bryant
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 experiments involving animals were performed according to IACUC protocol #2016N000369 at Brigham and Women's Hospital. All surgeries were performed while animals were anesthetized in tricaine. All experiments were planned and executed in manners that minimized animal suffering.
Copyright
© 2020, Sousounis 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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Eya2 promotes cell cycle progression by regulating DNA damage response during vertebrate limb regeneration
eLife 9:e51217.
https://doi.org/10.7554/eLife.51217
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