Hunan Provincial Key Laboratory of Phytohormones and Growth Development, College of Bioscience and Biotechnology, Hunan Agricultural University, Changsha 410128, China.
Hunan Academy of Agricultural Sciences, Changsha 410125, China.
Genes (Basel). 2022 Jun 9;13(6):1037. doi: 10.3390/genes13061037.
Replication factor C (RFC) is a heteropentameric ATPase associated with the diverse cellular activities (AAA+ATPase) protein complex, which is composed of one large subunit, known as RFC1, and four small subunits, RFC2/3/4/5. Among them, RFC1 and RFC3 were previously reported to mediate genomic stability and resistance to pathogens in . Here, we generated a viable () mutant with a single amino acid substitution by site-directed mutagenesis. Three of six positive T2 mutants with the same amino acid substitution, but different insertion loci, were sequenced to identify homozygotes, and the three homozygote mutants showed dwarfism, early flowering, and a partially sterile phenotype. RNA sequencing revealed that genes related to DNA repair and replication were highly upregulated. Moreover, the frequency of DNA lesions was found to be increased in mutants. Consistent with this, the mutants were very sensitive to DSB-inducing genotoxic agents. In addition, the G54E amino acid substitution in RFC4 delayed cell cycle progression and led to endoduplication. Overall, our study provides evidence supporting the notion that RFC4 plays an important role in resistance to genotoxicity and cell proliferation by regulating DNA damage repair in .
复制因子 C（RFC）是一种与多种细胞活动（AAA+ATP 酶）相关的异源五聚体 ATP 酶蛋白复合物，由一个大亚基（称为 RFC1）和四个小亚基（RFC2/3/4/5）组成。其中，RFC1 和 RFC3 先前被报道在 中介导基因组稳定性和对病原体的抗性。在这里，我们通过定点诱变产生了一个具有单个氨基酸取代的活的 () 突变体。对具有相同氨基酸取代但插入位置不同的六个阳性 T2 突变体中的三个进行测序以鉴定纯合子，这三个纯合子突变体表现出矮化、早花和部分不育的表型。RNA 测序显示与 DNA 修复和复制相关的基因高度上调。此外，在 突变体中发现 DNA 损伤的频率增加。与此一致， 突变体对诱导 DSB 的遗传毒性剂非常敏感。此外，RFC4 中的 G54E 氨基酸取代延迟细胞周期进程并导致内复制。总体而言，我们的研究提供了证据支持 RFC4 通过调节 中的 DNA 损伤修复在抗遗传毒性和细胞增殖中发挥重要作用的观点。
