1. Developmental Biology
  2. Stem Cells and Regenerative Medicine
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Damage-responsive, maturity-silenced enhancers regulate multiple genes that direct regeneration in Drosophila

  1. Robin E Harris  Is a corresponding author
  2. Michael J Stinchfield
  3. Spencer L Nystrom
  4. Daniel J McKay
  5. Iswar K Hariharan  Is a corresponding author
  1. Arizona State University, United States
  2. University of North Carolina at Chapel Hill, United States
  3. University of California, Berkeley, United States
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Cite this article as: eLife 2020;9:e58305 doi: 10.7554/eLife.58305

Abstract

Like tissues of many organisms, Drosophila imaginal discs lose the ability to regenerate as they mature. This loss of regenerative capacity coincides with reduced damage-responsive expression of multiple genes needed for regeneration. We previously showed that two such genes, wg and Wnt6, are regulated by a single damage-responsive enhancer that becomes progressively inactivated via Polycomb-mediated silencing as discs mature (Harris et al., 2016). Here we explore the generality of this mechanism and identify additional damage-responsive, maturity-silenced (DRMS) enhancers, some near genes known to be required for regeneration such as Mmp1, and others near genes that we now show function in regeneration. Using a novel GAL4-independent ablation system we characterize two DRMS-associated genes, apontic (apt), which curtails regeneration and CG9752/asperous (aspr), which promotes it. This mechanism of suppressing regeneration by silencing damage-responsive enhancers at multiple loci can be partially overcome by reducing activity of the chromatin regulator extra sex combs (esc).

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Author details

  1. Robin E Harris

    School of Life Sciences, Arizona State University, Tempe, United States
    For correspondence
    Robin.Harris@asu.edu
    Competing interests
    The authors declare that no competing interests exist.

  2. Michael J Stinchfield

    School of Life Sciences, Arizona State University, Tempe, United States
    Competing interests
    The authors declare that no competing interests exist.

  3. Spencer L Nystrom

    Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-1000-1579

  4. Daniel J McKay

    Curriculum in Genetics and Molecular Biology, University of North Carolina at Chapel Hill, Chapel Hill, United States
    Competing interests
    The authors declare that no competing interests exist.

  5. Iswar K Hariharan

    Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    For correspondence
    ikh@berkeley.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-6505-0744

Funding

National Institutes of Health (R35 GM122490)

  • Iswar K Hariharan

American Cancer Society (RP-16238-06-COUN)

  • Iswar K Hariharan

National Institutes of Health (R35 GM128851)

  • Daniel J McKay

American Cancer Society (RSG-17-164-01-DDC)

  • Daniel J McKay

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

Reviewing Editor

  1. Hugo J Bellen, Baylor College of Medicine, United States

Publication history

  1. Received: April 29, 2020
  2. Accepted: May 28, 2020
  3. Accepted Manuscript published: June 3, 2020 (version 1)
  4. Version of Record published: June 17, 2020 (version 2)

Copyright

© 2020, Harris 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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Further reading

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