O6-Methylguanine-DNA methyltransferase-defective human cell mutant: O6-methylguanine, DNA strand breaks and cytotoxicity
- 1 January 1988
- journal article
- research article
- Published by Oxford University Press (OUP) in Carcinogenesis: Integrative Cancer Research
- Vol. 9 (10) , 1749-1753
- https://doi.org/10.1093/carcin/9.10.1749
Abstract
We have isolated an isogenic O6-methylguanine (O6-MeG)-DNA methyltransferase-defective mutant from a HeLa cell line. This mutant exhibits excess DNA strand breaks and considerable cytotoxicity after N-methyl-N'-nitro-N-nitroso-guanidine (MNNG) treatment. The increased frequency ofstrand breaks after MNNG treatment was not abolished by DNA synthesis inhibitors. We propose that the presence of unrepaired O6-MeG lesions leads to excess strand breaks and these, in turn, are mainly responsible for the cytotoxicity.This publication has 3 references indexed in Scilit:
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