Establishment and maintenance of heritable chromatin structure during early Drosophila embryogenesis.

TitleEstablishment and maintenance of heritable chromatin structure during early Drosophila embryogenesis.
Publication TypeJournal Article
Year of Publication2016
AuthorsBlythe, SA, Wieschaus, EF
JournalElife
Volume5
Date Published2016 11 23
ISSN2050-084X
Abstract

During embryogenesis, the initial chromatin state is established during a period of rapid proliferative activity. We have measured with 3-min 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.

DOI10.7554/eLife.20148
Alternate JournalElife
PubMed ID27879204
PubMed Central IDPMC5156528
Grant ListF32 HD072653 / HD / NICHD NIH HHS / United States
R37 HD015587 / HD / NICHD NIH HHS / United States