Lambert C, Couto L B, Weiss W A, Schultz R A, Thompson L H, Friedberg E C
Department of Pathology, Stanford University School of Medicine, CA 94305.
EMBO J. 1988 Oct;7(10):3245-53. doi: 10.1002/j.1460-2075.1988.tb03191.x.
The RAD10 gene of Saccharomyces cerevisiae is required for nucleotide excision repair of DNA. Expression of RAD10 mRNA and Rad10 protein was demonstrated in Chinese hamster ovary (CHO) cells containing amplified copies of the gene, and RAD10 mRNA was also detected in stable transfectants without gene amplification. Following transfection with the RAD10 gene, three independently isolated excision repair-defective CHO cell lines from the same genetic complementation group (complementation group 2) showed partial complementation of sensitivity to killing by UV radiation and to the DNA cross-linking agent mitomycin C. These results were not observed when RAD10 was introduced into excision repair-defective CHO cell lines from other genetic complementation groups, nor when the yeast RAD3 gene was expressed in cells from genetic complementation group 2. Enhanced UV resistance in cells carrying the RAD10 gene was accompanied by partial reactivation of the plasmid-borne chloramphenicol acetyltransferase (cat) gene following its inactivation by UV radiation. The phenotype of CHO cells from genetic complementation group 2 is also specifically complemented by the human ERCC1 gene, and the ERCC1 and RAD10 genes have similar amino acid sequences. The present experiments therefore indicate that the structural homology between the yeast Rad10 and human Ercc1 polypeptides is reflected at a functional level, and suggest that nucleotide excision repair proteins are conserved in eukaryotes.
酿酒酵母的RAD10基因是DNA核苷酸切除修复所必需的。在含有该基因扩增拷贝的中国仓鼠卵巢（CHO）细胞中证实了RAD10 mRNA和Rad10蛋白的表达，并且在没有基因扩增的稳定转染子中也检测到了RAD10 mRNA。用RAD10基因转染后，来自同一遗传互补组（互补组2）的三个独立分离的切除修复缺陷型CHO细胞系对紫外线辐射和DNA交联剂丝裂霉素C的杀伤敏感性显示出部分互补。当将RAD10引入来自其他遗传互补组的切除修复缺陷型CHO细胞系时，或者当酵母RAD3基因在遗传互补组2的细胞中表达时，均未观察到这些结果。携带RAD10基因的细胞中紫外线抗性增强，同时其携带的质粒氯霉素乙酰转移酶（cat）基因在被紫外线辐射灭活后出现部分重新激活。来自遗传互补组2的CHO细胞的表型也被人ERCC1基因特异性互补，并且ERCC1和RAD10基因具有相似的氨基酸序列。因此，本实验表明酵母Rad10和人Ercc1多肽之间的结构同源性在功能水平上得以体现，并提示核苷酸切除修复蛋白在真核生物中是保守的。
