Chromatin accessibility established by Pou5f3, Sox19b and Nanog primes genes for activity during zebrafish genome activation

English version

Autoři: Máté Pálfy ^aff001; Gunnar Schulze ^aff002; Eivind Valen ^aff002; Nadine L. Vastenhouw ^aff001
Působiště autorů: Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany ^aff001; Computational Biology Unit, Department of Informatics, University of Bergen, Bergen, Norway ^aff002; Sars International Centre for Marine Molecular Biology, University of Bergen, Bergen, Norway ^aff003
Vyšlo v časopise: Chromatin accessibility established by Pou5f3, Sox19b and Nanog primes genes for activity during zebrafish genome activation. PLoS Genet 16(1): e32767. doi:10.1371/journal.pgen.1008546
Kategorie: Research Article
doi: https://doi.org/10.1371/journal.pgen.1008546

Souhrn

In many organisms, early embryonic development is driven by maternally provided factors until the controlled onset of transcription during zygotic genome activation. The regulation of chromatin accessibility and its relationship to gene activity during this transition remain poorly understood. Here, we generated chromatin accessibility maps with ATAC-seq from genome activation until the onset of lineage specification. During this period, chromatin accessibility increases at regulatory elements. This increase is independent of RNA polymerase II-mediated transcription, with the exception of the hypertranscribed miR-430 locus. Instead, accessibility often precedes the transcription of associated genes. Loss of the maternal transcription factors Pou5f3, Sox19b, and Nanog, which are known to be required for zebrafish genome activation, results in decreased accessibility at regulatory elements. Importantly, the accessibility of regulatory regions, especially when established by Pou5f3, Sox19b and Nanog, is predictive for future transcription. Our results show that the maternally provided transcription factors Pou5f3, Sox19b, and Nanog open up chromatin and prime genes for activity during zygotic genome activation in zebrafish.

Klíčová slova:

Embryos – Gene expression – Gene regulation – Chromatin – Mammalian genomics – Transcription factors – Transcriptional control – Zebrafish

Zdroje

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