Yang Jiayi, Zhang Xu, Feng Jianxun, Leng He, Li Shuqi, Xiao Junyu, Liu Shaofeng, Xu Zhiyun, Xu Jiawei, Li Di, Wang Zhongshi, Wang Jingyang, Li Qing
State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences and Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China.
State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences and Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China; Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China.
Cell Rep. 2016 Feb 9;14(5):1128-1141. doi: 10.1016/j.celrep.2015.12.096. Epub 2016 Jan 21.
DNA replication-coupled (RC) nucleosome assembly is mediated by histone chaperones and is fundamental for epigenetic inheritance and maintenance of genomic integrity. The mechanisms that promote this process are only partially understood. Here, we show that the histone chaperone FACT (facilitates chromatin transactions), consisting of Spt16 and Pob3, promotes newly synthesized histone H3-H4 deposition. We describe an allele of Spt16 (spt16-m) that has a defect in binding to H3-H4 and impairs their deposition onto DNA. Consistent with a direct role for FACT in RC nucleosome assembly, spt16-m displays synthetic defects with other histone chaperones associated with this process, CAF-1 and Rtt106. Importantly, we show that FACT physically associates with Rtt106 and that the acetylation of H3K56, a mark on newly synthesized H3, modulates this interaction. Therefore, FACT collaborates with CAF-1 and Rtt106 in RC nucleosome assembly.
DNA复制偶联(RC)核小体组装由组蛋白伴侣介导,是表观遗传继承和基因组完整性维持的基础。促进这一过程的机制仅得到部分理解。在这里,我们表明由Spt16和Pob3组成的组蛋白伴侣FACT(促进染色质交易)促进新合成的组蛋白H3-H4沉积。我们描述了一个Spt16等位基因(spt16-m),它在与H3-H4结合方面存在缺陷,并损害它们在DNA上的沉积。与FACT在RC核小体组装中的直接作用一致,spt16-m与参与此过程的其他组蛋白伴侣CAF-1和Rtt106表现出合成缺陷。重要的是,我们表明FACT与Rtt106发生物理相互作用,并且新合成的H3上的标记H3K56的乙酰化调节这种相互作用。因此,FACT在RC核小体组装中与CAF-1和Rtt106协作。