A Conserved Histone H3-H4 Interface Regulates DNA Damage Tolerance and Homologous Recombination during the Recovery from Replication Stress
A Conserved Histone H3-H4 Interface Regulates DNA Damage Tolerance and Homologous Recombination during the Recovery from Replication Stress
复制标题
DOI：
10.1128/mcb.00044-20
复制
发表时间：
2021-04-01
影响因子：
5.3
通讯作者：
Hishida，Takashi
中科院分区：
文献类型：
--
作者：
Hayashi，Masafumi;Keyamura，Kenji;Hishida，Takashi
在真核生物中，基因组DNA被包装成核小体，核小体是协调染色质结构和功能的基本成分。在这项研究中，我们在酿酒酵母中筛选了一组组蛋白H3/H4突变，这些突变会影响DNA损伤耐受性(DDT)缺陷细胞的DNA损伤敏感性。我们发现了一类组蛋白H3/H4突变，它们可以抑制DDT缺陷细胞对甲烷磺酸甲酯(MMS)的敏感性(这里称为组蛋白SDD突变)，这些突变可能聚集在核小体的特定H3-H4界面上。在缺乏RAD51的情况下，组蛋白SDD突变不能抑制DDT缺陷细胞对MMS的敏感性，表明同源重组(HR)与DNA损伤抗性有关。此外，组蛋白SDD突变体在暴露于MMS或紫外线照射后显示了降低的增殖细胞核抗原泛素化水平，这与相对于野生型细胞的MMS诱导的突变减少是一致的。我们还发现，缺乏INO80染色质重构体的组蛋白SDD突变体损害了从MMS诱导的复制停止中HR依赖的恢复，导致缺陷的S期进展和RAD52焦点的增加。综上所述，我们的数据为核小体功能提供了新的见解，这些功能将INO80依赖的染色质重塑与复制阻断恢复过程中DDT和HR的调节联系起来。
In eukaryotes, genomic DNA is packaged into nucleosomes, which are the basal components coordinating both the structures and functions of chromatin. In this study, we screened a collection of mutations for histone H3/H4 mutants inSaccharomyces cerevisiaethat affect the DNA damage sensitivity of DNA damage tolerance (DDT)-deficient cells. We identified a class of histone H3/H4 mutations that suppress methyl methanesulfonate (MMS) sensitivity of DDT-deficient cells (referred to here as the histone SDD mutations), which likely cluster on a specific H3-H4 interface of the nucleosomes. The histone SDD mutations did not suppress the MMS sensitivity of DDT-deficient cells in the absence of Rad51, indicating that homologous recombination (HR) is responsible for DNA damage resistance. Furthermore, the histone SDD mutants showed reduced levels of PCNA ubiquitination after exposure to MMS or UV irradiation, consistent with decreased MMS-induced mutagenesis relative to that of wild-type cells. We also found that histone SDD mutants lacking the INO80 chromatin remodeler impair HR-dependent recovery from MMS-induced replication arrest, resulting in defective S-phase progression and increased Rad52 foci. Taken together, our data provide novel insights into nucleosome functions, which link INO80-dependent chromatin remodeling to the regulation of DDT and HR during the recovery from replication blockage.