1. Chromosomes and Gene Expression
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GAF is essential for zygotic genome activation and chromatin accessibility in the early Drosophila embryo

  1. Marissa M Gaskill
  2. Tyler J Gibson
  3. Elizabeth D Larson
  4. Melissa M Harrison  Is a corresponding author
  1. University of Wisconsin-Madison, United States
Research Article
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Cite this article as: eLife 2021;10:e66668 doi: 10.7554/eLife.66668

Abstract

Following fertilization, the genomes of the germ cells are reprogrammed to form the totipotent embryo. Pioneer transcription factors are essential for remodeling the chromatin and driving the initial wave of zygotic gene expression. In Drosophila melanogaster, the pioneer factor Zelda is essential for development through this dramatic period of reprogramming, known as the maternal-to-zygotic transition (MZT). However, it was unknown whether additional pioneer factors were required for this transition. We identified an additional maternally encoded factor required for development through the MZT, GAGA Factor (GAF). GAF is necessary to activate widespread zygotic transcription and to remodel the chromatin accessibility landscape. We demonstrated that Zelda preferentially controls expression of the earliest transcribed genes, while genes expressed during widespread activation are predominantly dependent on GAF. Thus, progression through the MZT requires coordination of multiple pioneer-like factors, and we propose that as development proceeds control is gradually transferred from Zelda to GAF.

Data availability

Sequencing data have been deposited in GEO under accession code GSE152773.

The following data sets were generated
The following previously published data sets were used

Article and author information

Author details

  1. Marissa M Gaskill

    Department of Biomolecular Chemistry, University of Wisconsin-Madison, Madison, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Tyler J Gibson

    Department of Biomolecular Chemistry, University of Wisconsin-Madison, Madison, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Elizabeth D Larson

    Department of Biomolecular Chemistry, University of Wisconsin-Madison, Madison, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Melissa M Harrison

    Department of Biomolecular Chemistry, University of Wisconsin-Madison, Madison, United States
    For correspondence
    mharrison3@wisc.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-8228-6836

Funding

National Institutes of Health (R01GM111694)

  • Melissa M Harrison

National Institutes of Health (R35GM136298)

  • Melissa M Harrison

Vallee Foundation

  • Melissa M Harrison

National Institutes of Health (T32GM007215)

  • Marissa M Gaskill
  • Tyler J Gibson

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

Reviewing Editor

  1. Yukiko M Yamashita, Whitehead Institute/MIT, United States

Publication history

  1. Received: January 19, 2021
  2. Accepted: March 14, 2021
  3. Accepted Manuscript published: March 15, 2021 (version 1)

Copyright

© 2021, Gaskill 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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