DNA alkylations and mutation after exposure to ethyl methanesulphonate in mammalian cell lines routinely used in mutagenicity testing.
DNA ethylations were measured in four mammalian cell lines, Chinese hamster ovary CHO, mouse lymphoma L5178Y t k+/-, human lymphoblastoid TK6 and Chinese hamster V79, following exposure to [3H]ethyl methanesulphonate. Concurrent estimates of cytotoxicity and gene mutation were also carried out. Total DNA-binding and relative levels of ethylation at N-7 guanine (N-7G), O6 guanine (O6G) and N-3 adenine (N-3A) were essentially the same in all four cell lines. Differences in response to EMS between the cell lines, namely the greater cytotoxicity in TK6 cells, would therefore appear to reflect subsequent handling of the DNA lesions, rather than different levels of DNA ethylation in the cell lines.
School of Biological Sciences, University College of Swansea, UK.
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Waters
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Henderson
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Wilcox
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MR
O'Donovan
D000225:Adenine / Q000378:metabolism; D000478:Alkylation; D000818:Animals; D002460:Cell Line; D002851:Chromatography, High Pressure Liquid; D004247:DNA / Q000378:metabolism; D004249:DNA Damage; D005020:Ethyl Methanesulfonate / Q000378:metabolism / Q000633:toxicity*; D006147:Guanine / Q000378:metabolism; D006801:Humans; D009152:Mutagenicity Tests / Q000379:methods*; D009153:Mutagens / Q000378:metabolism / Q000633:toxicity*; D009154:Mutation; D014316:Tritium
D009153:Mutagens; D014316:Tritium; D006147:Guanine; D004247:DNA; D005020:Ethyl Methanesulfonate; D000225:Adenine