Towards Understanding the Roles of Histone H3 serine 10 Phosphorylation in Mouse Embryonic Stem Cells

摘要

Histone H3 serine 10 phosphorylation (H3S10ph) is a histone posttranslational modification (PTM) mark that is highly enriched in mitosis. In multiple model organisms tested, H3S10ph is required for chromosome condensation and/or segregation. H3S10ph has also been shown to be associated with active transcription in interphase. We showed that H3S10ph is highly enriched in mammalian embryonic stem cells (ESCs), indicating a potential role of H3S10ph in pluripotency. We hypothesize that H3S10ph has a role in the transcriptional regulation and interplays with other histone PTMs to regulate transcription in ESCs. To investigate the roles of H3S10ph in ESCs, we first characterized the levels of H3S10ph, in combination of a few other histone PTMs on the H3 9-17 peptide. We showed that H3S10ph often coexist with methylation (me) of H3 lysine 9 (H3K9), in both mouse ESCs and Hela cells, indicating crosstalk between K9me and S10ph. In order to test if enrichment of H3S10ph in mouse ESCs are cell cycle-dependent, we additionally quantify H3S10ph based on the stages of cell cycle. The majority of H3S10ph signal was observed in mitotic cells. However, H3S10ph may still have a transcriptional role in ESCs. Chromatin Immunoprecipitation followed by deep sequencing (ChIP-seq) experiments will be performed to identify sequence-specific localization of H3S10ph in mouse ESCs, throughout the cell cycle.