TY - JOUR T1 - Mitotic H3K9ac is controlled by phase-specific activity of HDAC2, HDAC3, and SIRT1 JF - Life Science Alliance JO - Life Sci. Alliance DO - 10.26508/lsa.202201433 VL - 5 IS - 10 SP - e202201433 AU - Shashi Gandhi AU - Raizy Mitterhoff AU - Rachel Rapoport AU - Marganit Farago AU - Avraham Greenberg AU - Lauren Hodge AU - Sharon Eden AU - Christopher Benner AU - Alon Goren AU - Itamar Simon Y1 - 2022/10/01 UR - https://www.life-science-alliance.org/content/5/10/e202201433.abstract N2 - Histone acetylation levels are reduced during mitosis. To study the mitotic regulation of H3K9ac, we used an array of inhibitors targeting specific histone deacetylases. We evaluated the involvement of the targeted enzymes in regulating H3K9ac during all mitotic stages by immunofluorescence and immunoblots. We identified HDAC2, HDAC3, and SIRT1 as modulators of H3K9ac mitotic levels. HDAC2 inhibition increased H3K9ac levels in prophase, whereas HDAC3 or SIRT1 inhibition increased H3K9ac levels in metaphase. Next, we performed ChIP-seq on mitotic-arrested cells following targeted inhibition of these histone deacetylases. We found that both HDAC2 and HDAC3 have a similar impact on H3K9ac, and inhibiting either of these two HDACs substantially increases the levels of this histone acetylation in promoters, enhancers, and insulators. Altogether, our results support a model in which H3K9 deacetylation is a stepwise process—at prophase, HDAC2 modulates most transcription-associated H3K9ac-marked loci, and at metaphase, HDAC3 maintains the reduced acetylation, whereas SIRT1 potentially regulates H3K9ac by impacting HAT activity. ER -