Sumoylation of the human histone H4 tail inhibits p300-mediated transcription by RNA polymerase II in cellular extracts.
Sumoylation of the human histone H4 tail inhibits p300-mediated transcription by RNA polymerase II in cellular extracts.
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DOI：
10.7554/elife.67952
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发表时间：
2021-11-08
期刊：
影响因子：
7.7
通讯作者：
Chatterjee C
中科院分区：
文献类型：
--
作者：
Leonen CJA;Shimada M;Weller CE;Nakadai T;Hsu PL;Tyson EL;Mishra A;Shelton PM;Sadilek M;Hawkins RD;Zheng N;Roeder RG;Chatterjee C
在真核生物中，小泛素样修饰物（SUMO）蛋白对组蛋白的翻译后修饰与基因调控、着丝粒定位和双链断裂修复有关。尽管组蛋白H4的summoylation与基因抑制特异性相关，但由于在细胞中位点特异性summoylation H4的挑战，这一点无法得到证实。SUMO与其他与活性基因相关的组蛋白修饰（如H4乙酰化和H3甲基化）之间的生化串扰也尚不清楚。我们在机制研究中解决了这些挑战，使用SUMO-3在Lys12位点进行化学修饰的H4 (H4K12su)，并将其纳入单核小体和染色质粒中进行功能研究。基于单核小体的分析显示，H4K12su抑制组蛋白乙酰转移酶p300介导的转录激活H4尾部乙酰化，以及Set1/COMPASS（与Set1相关的蛋白复合物）组蛋白甲基转移酶复合物扩展催化模块介导的转录相关H3K4甲基化。用染色质粒进行的体外转录实验显示，H4K12su抑制H4尾乙酰化和RNA聚合酶ii介导的转录。最后，模拟H4尾部SUMO-H4融合的细胞实验证实了组蛋白sumo化和乙酰化/甲基化之间的负串扰。因此，我们的研究确定了组蛋白sumo化在人类细胞中基因沉默及其与活性转录相关标记的负生化串扰中的关键作用。
The post-translational modification of histones by the small ubiquitin-like modifier (SUMO) protein has been associated with gene regulation, centromeric localization, and double-strand break repair in eukaryotes. Although sumoylation of histone H4 was specifically associated with gene repression, this could not be proven due to the challenge of site-specifically sumoylating H4 in cells. Biochemical crosstalk between SUMO and other histone modifications, such as H4 acetylation and H3 methylation, that are associated with active genes also remains unclear. We addressed these challenges in mechanistic studies using an H4 chemically modified at Lys12 by SUMO-3 (H4K12su) and incorporated into mononucleosomes and chromatinized plasmids for functional studies. Mononucleosome-based assays revealed that H4K12su inhibits transcription-activating H4 tail acetylation by the histone acetyltransferase p300, as well as transcription-associated H3K4 methylation by the extended catalytic module of the Set1/COMPASS (complex of proteins associated with Set1) histone methyltransferase complex. Activator- and p300-dependent in vitro transcription assays with chromatinized plasmids revealed that H4K12su inhibits both H4 tail acetylation and RNA polymerase II-mediated transcription. Finally, cell-based assays with a SUMO-H4 fusion that mimics H4 tail sumoylation confirmed the negative crosstalk between histone sumoylation and acetylation/methylation. Thus, our studies establish the key role for histone sumoylation in gene silencing and its negative biochemical crosstalk with active transcription-associated marks in human cells.