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Histone variant H2A.Z regulates nucleosome unwrapping and CTCF binding in mouse ES cells

ABSTRACT: Nucleosome is the basic structural unit of chromatin, and its dynamics plays critical roles in the regulation of genome functions. However, how the nucleosome structure is regulated by histone variants in vivo is still largely uncharacterized. Here, by employing Micrococcal nuclease (MNase) digestion of crosslinked chromatin followed by chromatin immunoprecipitation (ChIP) and paired-end sequencing (MNase-X-ChIP-seq), we mapped genome-wide unwrapping states of nucleosomes containing histone variant H2A.Z in mouse embryonic stem (ES) cells. We found that H2A.Z is enriched with unwrapped nucleosomes. Interestingly, the function of +1 H2A.Z nucleosome in transcriptional regulation is correlated with the unwrapping states. We further showed that H2A.Z nucleosomes adjacent the CTCF binding sites (CBS) may adopt an open conformation. We confirmed the unwrapping state of H2A.Z nucleosomes under native condition by re-ChIP of H2A.Z after CTCF CUT&RUN in mouse ES cells. Importantly, we found that depletion of H2A.Z results in increased CTCF binding, indicating dynamic competition between the unwrapped H2A.Z nucleosomal intermediates and CTCF at the CBS. Taken together, our results showed that histone variant H2A.Z regulates transcription and CTCF binding through modulating the nucleosome unwrapping.

ORGANISM(S): Mus musculus

PROVIDER: GSE146082 | GEO | 2020/04/27

REPOSITORIES: GEO

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Histone variant H2A.Z regulates nucleosome unwrapping and CTCF binding in mouse ES cells

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