Phosphorylation of histone H3 at serine 10 (H3S10ph) by Aurora kinases plays an important role in mitosis; however, H3S10ph also marks regulatory regions of inducible genes in interphase mammalian cells, implicating mitosis-independent functions. Using the fluorescent ubiquitin-mediated cell cycle indicator (FUCCI), we found that 30% of the genome in interphase mouse embryonic stem cells (ESCs) is marked with H3S10ph. H3S10ph broadly demarcates gene-rich regions in G1 and is positively correlated with domains of early DNA replication timing (RT) but negatively correlated with H3K9me2 and lamin-associated domains (LADs). Consistent with mitosis-independent kinase activity, this pattern was preserved in ESCs treated with Hesperadin, a potent inhibitor of Aurora B/C kinases. Disruption of H3S10ph by expression of nonphosphorylatable H3.3S10A results in ectopic spreading of H3K9me2 into adjacent euchromatic regions, mimicking the phenotype observed in Drosophila JIL-1 kinase mutants. Conversely, interphase H3S10ph domains expand in Ehmt1 (also known as Glp) null ESCs, revealing that H3S10ph deposition is restricted by H3K9me2. Strikingly, spreading of H3S10ph at RT transition regions (TTRs) is accompanied by aberrant transcription initiation of genes co-oriented with the replication fork in Ehmt1^−/− and Ehmt2^−/− ESCs, indicating that establishment of repressive chromatin on the leading strand following DNA synthesis may depend upon these lysine methyltransferases. H3S10ph is also anti-correlated with H3K9me2 in interphase murine embryonic fibroblasts (MEFs) and is restricted to intragenic regions of actively transcribing genes by EHMT2. Taken together, these observations reveal that H3S10ph may play a general role in restricting the spreading of repressive chromatin in interphase mammalian cells.

Aurora激酶使丝氨酸10（H3S10ph）处的组蛋白H3磷酸化在有丝分裂中起重要作用；然而，H3S10ph还标记了相间哺乳动物细胞中可诱导基因的调控区，暗示了有丝分裂非依赖性功能。使用荧光泛素介导的细胞周期指示器（FUCCI），我们发现相间小鼠胚胎干细胞（ESCs）中30％的基因组标记有H3S10ph。H3S10ph广泛划定了G1中的基因富集区域，并且与早期DNA复制时机（RT）的域呈正相关，而与H3K9me2和层蛋白相关的域（LAD）则呈负相关。与不依赖有丝分裂的激酶活性一致，这种模式在用Hesperadin处理的ESC中得以保留，而Hesperadin是Aurora B / C激酶的有效抑制剂。通过不可磷酸化的H3的表达破坏H3S10ph。果蝇JIL-1激酶突变体。相反，相间H3S10ph域在Ehmt1（也称为Glp）空ESC中扩展，表明H3S10ph沉积受到H3K9me2的限制。令人惊讶的是，H3S10ph在RT过渡区（TTR）的扩散伴随着与Ehmt1 ^-/-和Ehmt2 ^-/-中的复制叉共同定向的基因的异常转录起始ESC，表明在DNA合成后前导链上抑制性染色质的建立可能取决于这些赖氨酸甲基转移酶。H3S10ph在相间鼠胚胎成纤维细胞（MEF）中也与H3K9me2抗相关，并且被EHMT2限制在活跃转录基因的基因内区域。综上所述，这些观察结果表明，H3S10ph可能在限制抑制性染色质在相间哺乳动物细胞中的扩散中起一般作用。