Genetic studies on the interaction between base excision repair and recombinational repair using human gene knockout cells

在这项研究中，我们进行了遗传分析之间的相互作用的碱基切除修复和重组修复在人类细胞。具体而言，我们通过使用Nalm-6细胞的基因靶向破坏了分别参与碱基切除修复同源重组或非同源末端连接的PolB、Rad 54和Lig 4基因。此外，我们试图为这些基因制造双敲除突变细胞系。我们研究了这些突变体的生长速率、细胞周期分布和重组能力。此外，使用这些突变体，我们已经成功地分析了细胞的敏感性，以各种遗传毒性剂，如X-射线，紫外线，烷化剂，过氧化氢，拓扑异构酶抑制剂，和复制应力。这些研究使我们得出结论，同源重组对于修复由单链断裂引起的DNA双链断裂是重要的。最重要的是，这项工作突出了人类细胞中DNA聚合酶β和DNA连接酶W之间的遗传相互作用。

In this study, we have performed genetic analysis on the interaction between base excision repair and recombinational repair in human cells. Specifically, we disrupted, by means of gene targeting using Nalm-6 cells, the PolB, Rad54, and Lig4 genes involved in base excision repair homologous recombination, or nonhomologous end-joining, respectively. Additionally, we tried to make double-knockout mutant cell lines for those genes. We investigated the growth rate, cell cycle distributions, and recombination capacity of these mutants. Furthermore, using these mutants, we have successfully analyzed cellular sensitivity to a variety of genotoxic agents such as X-rays, UV light, alkylating agents, hydrogen peroxide, topoisomerase inhibitors, and replication stress. These studies led us to conclude that homologous recombination is important for repairing DNA double-strand breaks that arose from single-strand breaks. Most importantly, this work has highlighted the genetic interaction between DNApolymerase beta and DNAligase W in human cells.