Odd-paired is a pioneer-like factor that coordinates with Zelda to control gene expression in embryos
Abstract
Pioneer factors such as Zelda (Zld) help initiate zygotic transcription in Drosophila early embryos, but whether other factors support this dynamic process is unclear. Odd-paired (Opa), a zinc-finger transcription factor expressed at cellularization, controls the transition of genes from pair-rule to segmental patterns along the anterior-posterior axis. Finding that Opa also regulates expression through enhancer sog_Distal along the dorso-ventral axis, we hypothesized Opa’s role is more general. Chromatin-immunoprecipitation (ChIP-seq) confirmed its in vivo binding to sog_Distal but also identified widespread binding throughout the genome, comparable to Zld. Furthermore, chromatin assays (ATAC-seq) demonstrate that Opa, like Zld, influences chromatin accessibility genome-wide at cellularization, suggesting both are pioneer factors with common as well as distinct targets. Lastly, embryos lacking opa exhibit widespread, late patterning defects spanning both axes. Collectively, these data suggest Opa is a general timing factor and likely late-acting pioneer factor that drives a secondary wave of zygotic gene expression.
Data availability
GEO accession number SuperSeries GSE153329. SubSeries: ChIP-seq and singled-end ATAC-seq (GSE140722), and RNA-seq and paired-end ATAC-seq data access (GSE153328).RNA-seq and paired-end ATAC-seq data access: https://www.ncbi.nlm.nih.gov/geo/info/submissionftp.html, folder name: GEO_Theodora and Directory name: uploads/tkoromila_YTqdmKKoThe codes for RNA-seq, Opa ChIP-seq and ATAC-seq processing (alignment and peak calling) were uploaded to github: https://github.com/caltech-bioinformatics-resource-center/Stathopoulos_Lab
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ChIP-seq and singled-end ATAC-seqNCBI Gene Expression Omnibus, GSE140722.
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RNA-seq and paired-end ATAC-seq dataNCBI Gene Expression Omnibus, GSE153328.
Article and author information
Author details
Funding
National Institute of General Medical Sciences (R35GM118146)
- Angelike Stathopoulos
Eunice Kennedy Shriver National Institute of Child Health and Human Development (R03HD097535)
- Angelike Stathopoulos
Bioinformatics Resource Center at the Beckman Institute of Caltech (n/a)
- Fan Gao
Stony Brook University College of Arts and Sciences (n/a)
- J Peter Gergen
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2020, Koromila 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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