Hansson J, Grossman L, Lindahl T, Wood R D
Imperial Cancer Research Fund, Clare Hall Laboratories, Herts, UK.
Nucleic Acids Res. 1990 Jan 11;18(1):35-40. doi: 10.1093/nar/18.1.35.
A newly developed cell-free system was used to study DNA repair synthesis carried out by extracts from human cell lines in vitro. Extracts from a normal human lymphoid cell line and from cell lines established from individuals with hereditary dysplastic nevus syndrome perform damage-dependent repair synthesis in plasmid DNA treated with cis- or trans-diamminedichloro-platinum(II) or irradiated with ultraviolet light. Cell extracts of xeroderma pigmentosum origin (complementation groups A, C, D, and G) are deficient in DNA repair synthesis. When damaged plasmid DNA was pretreated with purified Escherichia coli UvrABC proteins, xeroderma pigmentosum cell extracts were able to carry out DNA repair synthesis. The ability of E. coli UvrABC proteins to complement xeroderma pigmentosum cell extracts indicates that the extracts are deficient in incision, but can carry out later steps of repair. Thus the in vitro system provides results that are in agreement with the incision defect found from studies of xeroderma pigmentosum cells.
一种新开发的无细胞系统被用于研究人细胞系提取物在体外进行的DNA修复合成。来自正常人淋巴细胞系以及来自遗传性发育异常痣综合征患者所建立的细胞系的提取物，在经顺式或反式二氯二氨合铂（II）处理或紫外线照射的质粒DNA中进行损伤依赖性修复合成。着色性干皮病来源的细胞提取物（互补组A、C、D和G）在DNA修复合成方面存在缺陷。当用纯化的大肠杆菌UvrABC蛋白预处理受损的质粒DNA时，着色性干皮病细胞提取物能够进行DNA修复合成。大肠杆菌UvrABC蛋白补充着色性干皮病细胞提取物的能力表明，提取物在切口方面存在缺陷，但能够进行修复的后续步骤。因此，该体外系统提供的结果与对着色性干皮病细胞研究中发现的切口缺陷一致。
