The chromatin remodeling protein INO80 contributes to the removal of H2A.Z at the p53-binding site of the p21 gene in response to doxorubicin
The chromatin remodeling protein INO80 contributes to the removal of H2A.Z at the p53-binding site of the p21 gene in response to doxorubicin
复制标题
染色质重塑蛋白 INO80 有助于去除 p21 基因 p53 结合位点上的 H2A.Z，以响应阿霉素
DOI：
10.1111/febs.14615
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发表时间：
2018-09-01
期刊：
影响因子：
5.4
通讯作者：
Jin, Jingji
中科院分区：
文献类型：
--
作者：
Ding, Jian;Yu, Chao;Jin, Jingji
DNA损伤引起的p21(细胞周期蛋白依赖性激酶抑制因子1A)转录激活常常改变组蛋白变异体H_2A.Z在p21基因上的分布。然而，人类INO80复合体是否调节p21启动子上的H2A.Z的变化尚不清楚。我们在这里表明，在p21启动子的p53结合位点近端区域(-2.2kb)，INO80需要用阿霉素(Doxo)激活U2OS细胞中p21的表达，以消除H2A.Z。纯化的INO80复合体，而不是失去DNA滑动活性的INO80E653Q突变复合体，主要负责从体外重组的核小体中去除H2A.Z。这一活性通过MOF介导组蛋白乙酰化而增强，这表明INO80更容易从松散的核小体中去除H2A.Z。此外，还观察到INO80和H2A.Z-2.2kb位于p21转录起始点(TSS)上游。Doxo处理后，该区域的H_2A.Z在短时间内被清除，并激活了p21的表达。然而，INO80通过延迟H2A.Z的清除而抑制了p21的诱导，这表明需要INO80。此外，shMOF介导组蛋白乙酰化减少了p21TSS上游INO80-2.2kb的募集，并抑制了Doxo处理的细胞中H2A.Z的清除。这些数据为INO80复合体对p21的转录调控提供了新的见解。
Transcriptional activation of p21 (cyclin-dependent kinase inhibitor 1A) due to DNA damage often alters the distribution of histone variant H2A.Z at the p21 gene. However, whether the human INO80 complex regulates changes in H2A.Z at the p21 promoter is unclear. We show here that activation of p21 expression by doxorubicin (Doxo) in U2OS cells is required for removal of H2A.Z by INO80 at the p53-binding site proximal region (-2.2 kb) of the p21 promoter. A purified INO80 complex, but not the INO80E653Q mutant-complex, which lost DNA-sliding activity, is mainly responsible for removing H2A.Z from reconstituted nucleosomes in vitro. This activity was enhanced with MOF-mediated histone acetylation, suggesting that INO80 more readily removes H2A.Z from loosened nucleosomes. Also, co-occupancy of INO80 and H2A.Z -2.2 kb upstream of the p21 transcriptional start site (TSS) was observed. H2A.Z at this region was removed in a short time after Doxo treatment and activated p21 expression. However, p21 induction was inhibited by INO80 knockdown by delaying H2A.Z removal, indicating the need for INO80. Moreover, shMOF-mediated histone acetylation reduced recruitment of INO80 -2.2 kb upstream of p21 TSS and inhibited the removal of H2A.Z in Doxo-treated cells. These data provide new insights into the transcriptional regulation of p21 by the INO80 complex.