Establishment and maintenance of heritable chromatin structure during early Drosophila embryogenesis

  1. Shelby A Blythe  Is a corresponding author
  2. Eric F Wieschaus  Is a corresponding author
  1. Howard Hughes Medical Institute, Princeton University, United States

Abstract

During embryogenesis, the initial chromatin state is established during a period of rapid proliferative activity. We have measured with three-minute time resolution how heritable patterns of chromatin structure are initially established and maintained during the midblastula transition (MBT). We find that regions of accessibility are established sequentially, where enhancers are opened in advance of promoters and insulators. These open states are stably maintained in highly condensed mitotic chromatin to ensure faithful inheritance of prior accessibility status across cell divisions. The temporal progression of establishment is controlled by the biological timers that control the onset of the MBT. In general, acquisition of promoter accessibility is controlled by the biological timer that measures the nucleo-cytoplasmic (N:C) ratio whereas timing of enhancer accessibility is regulated independently of the N:C ratio. These different timing classes each associate with binding sites for two transcription factors, GAGA-factor and Zelda, previously implicated in controlling chromatin accessibility at ZGA.

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Article and author information

Author details

  1. Shelby A Blythe

    Howard Hughes Medical Institute, Princeton University, Princeton, United States
    For correspondence
    sblythe@princeton.edu
    Competing interests
    The authors declare that no competing interests exist.
  2. Eric F Wieschaus

    Howard Hughes Medical Institute, Princeton University, Princeton, United States
    For correspondence
    efw@princeton.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-0727-3349

Funding

National Institutes of Health (F32HD072653)

  • Shelby A Blythe

Howard Hughes Medical Institute

  • Shelby A Blythe
  • Eric F Wieschaus

National Institutes of Health (R37HD15587)

  • Eric F Wieschaus

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

Reviewing Editor

  1. Allan C Spradling, Howard Hughes Medical Institute, Carnegie Institution for Science, United States

Version history

  1. Received: July 28, 2016
  2. Accepted: November 21, 2016
  3. Accepted Manuscript published: November 23, 2016 (version 1)
  4. Version of Record published: December 14, 2016 (version 2)

Copyright

© 2016, Blythe & Wieschaus

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. Shelby A Blythe
  2. Eric F Wieschaus
(2016)
Establishment and maintenance of heritable chromatin structure during early Drosophila embryogenesis
eLife 5:e20148.
https://doi.org/10.7554/eLife.20148

Share this article

https://doi.org/10.7554/eLife.20148

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