Dynamic regulation of histone modifications and long-range chromosomal interactions during post-mitotic transcriptional reactivation [Hi-C]

ABSTRACT: During mitosis, transcription of genomic DNA is dramatically reduced, before its reactivation occurs during nuclear reformation in anaphase/telophase. Many aspects of the underlying principles that mediate transcriptional memory and reactivation in the daughter cells remain unclear. Here, we used ChIP-seq on synchronized cells at different stages after mitosis to generate genome-wide maps of histone modifications. In combination with EU-RNA-seq and Hi-C analyses, we show that, during prometaphase, promoters, enhancers, and insulators retain H3K4me3 and H3K4me1, while losing H3K27ac. Enhancers harboring mitotic H3K4me1 are associated with cell type-specific transcription factor motifs and mitotic activation of cell identity genes. As cells exit mitosis, promoters regain H3K27ac, which correlates with transcriptional reactivation. Insulators also gain H3K27ac and CCCTC binding factors (CTCF) in anaphase/telophase. This increase may play a role in the establishment of topologically associating domains (TADs). Together, our results show that the genome is reorganized in sequential order, in which histone methylations occur first in prometaphase, histone acetylation and CTCF in anaphase/telophase, transcription in cytokinesis, and long-range chromatin interactions in early G1. Our results provide insights into the histone modification landscape that allows faithful reestablishment of the transcriptional program and TADs during cell division.

ORGANISM(S): Homo sapiens

PROVIDER: GSE141067 | GEO | 2020/06/11

REPOSITORIES: GEO