CLAMP and Zelda function together to promote Drosophila zygotic genome activation
Abstract
During the essential and conserved process of zygotic genome activation (ZGA), chromatin accessibility must increase to promote transcription. Drosophila is a well-established model for defining mechanisms that drive ZGA. Zelda (ZLD) is a key pioneer transcription factor (TF) that promotes ZGA in the Drosophila embryo. However, many genomic loci that contain GA-rich motifs become accessible during ZGA independent of ZLD. Therefore, we hypothesized that other early TFs that function with ZLD have not yet been identified, especially those that are capable of binding to GA-rich motifs such as CLAMP. Here, we demonstrate that Drosophila embryonic development requires maternal CLAMP to: 1) activate zygotic transcription; 2) increase chromatin accessibility at promoters of specific genes that often encode other essential TFs; 3) enhance chromatin accessibility and facilitate ZLD occupancy at a subset of key embryonic promoters. Thus, CLAMP functions as a pioneer factor which plays a targeted yet essential role in ZGA.
Data availability
To review GEO accession GSE152613:Go to https://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE152613Enter token ihevsmiqnxexrod into the box
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Funding
National Institute of General Medical Sciences (F32GM109663)
- Leila Rieder
National Institute of General Medical Sciences (K99HD092625)
- Leila Rieder
National Institute of General Medical Sciences (R00HD092625)
- Leila Rieder
National Institute of General Medical Sciences (R35GM126994)
- Erica Larschan
National Science Foundation (1845734)
- Nicolas Fawzi
National Institute of General Medical Sciences (R01GM118530)
- Nicolas Fawzi
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2021, Duan 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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