Kaur G P, Athwal R S
Department of Microbiology and Molecular Genetics, New Jersey Medical School, Newark 07103.
Somat Cell Mol Genet. 1993 Jan;19(1):83-93. doi: 10.1007/BF01233957.
Complementation of DNA excision repair defect in xeroderma pigmentosum cells of group C (XP-C) has been achieved by the transfer of human chromosome 5. Individual human chromosomes tagged with a selectable marker were transferred to XP-C cells by microcell fusion from mouse-human hybrid cell lines each bearing a single different human chromosome. Analysis of the chromosome transfer clones revealed that introduction of chromosome 5 into XP-C cells corrected the DNA repair defect as well as UV-sensitive phenotypes, while chromosomes 2, 6, 7, 9, 13, 15, 17, and 21 failed to complement. The introduced chromosome 5 in complemented UVr clones was distinguished from the parental XP-C chromosomes by polymorphism for dinucleotide (CA)n repeats at two loci, D5S117 and D5S209. In addition, an intact marked chromosome 5 was rescued into mouse cells from a complemented UVr clone by microcell fusion. Five subclones of a complemented clone that had lost the marked chromosome 5 exhibited UV-sensitive and repair-deficient phenotypes identical to parental XP-C cells. Concordant loss of the transferred chromosome and reappearance of XP-C phenotype further confirmed the presence of a DNA repair gene on human chromosome 5.
通过转移人类5号染色体，已实现对C组着色性干皮病（XP - C）细胞中DNA切除修复缺陷的互补。用可选择标记标记的单个人类染色体通过微细胞融合从每个携带一条不同人类染色体的小鼠 - 人类杂交细胞系转移到XP - C细胞中。对染色体转移克隆的分析表明，将5号染色体导入XP - C细胞可纠正DNA修复缺陷以及紫外线敏感表型，而2号、6号、7号、9号、13号、15号、17号和21号染色体未能实现互补。在互补的UVr克隆中引入的5号染色体通过两个位点D5S117和D5S209处二核苷酸（CA）n重复序列的多态性与亲本XP - C染色体区分开来。此外，通过微细胞融合从一个互补的UVr克隆中将一条完整的标记5号染色体拯救到小鼠细胞中。一个失去标记5号染色体的互补克隆的五个亚克隆表现出与亲本XP - C细胞相同的紫外线敏感和修复缺陷表型。转移染色体的一致丢失和XP - C表型的重新出现进一步证实了人类5号染色体上存在一个DNA修复基因。
