Correction of alkylation hypersensitivity of CHO-W27-1 cells by transfection with human DNA.
Chinese hamster cells of the mutant strain W27-1 which is hypersensitive to UV and monofunctional alkylating agents were transfected with human DNA ligated to the bacterial xanthine-guanine phosphoribosyltransferase (gpt) gene. Selection was performed for resistance to mycophenolic acid and finally for survival after treatment with high doses of methyl methanesulfonate. A gpt+ transfectant was generated (T38-2-7) which acquired resistance to methyl methanesulfonate and cross-resistance to N-methyl-N'-nitro-N-nitrosoguanidine at levels comparable with the parental (wild-type) strain CHO-9. T38-2-7 cells were not more resistant, however, to UV, mitomycin C and N-hydroxyethyl-N-chloroethylnitrosourea than the mutant W27-1. The transfectant contains integrated human DNA and was shown to be deficient for the O6-methylguanine-DNA methyltransferase. The results indicate that the transfected DNA specifically complemented the defect underlying alkylation hypersensitivity of W27-1 cells or that a gene was transfected which is generally inactive in CHO cells and which causes alkylation resistance.
Kaina
B
B
Laboratory of Molecular Genetics, State University of Leiden, The Netherlands.
D000478:Alkylation; D000818:Animals; D006224:Cricetinae; D003412:Cricetulus; D004247:DNA / Q000378:metabolism*; D008741:Methyl Methanesulfonate / Q000494:pharmacology; D008769:Methylnitronitrosoguanidine / Q000494:pharmacology; D008770:Methylnitrosourea / Q000494:pharmacology; D008780:Methyltransferases / Q000378:metabolism; D019853:O(6)-Methylguanine-DNA Methyltransferase; D014162:Transfection
D008769:Methylnitronitrosoguanidine; D008770:Methylnitrosourea; D004247:DNA; D008741:Methyl Methanesulfonate; D008780:Methyltransferases; D019853:O(6)-Methylguanine-DNA Methyltransferase