title: DNA alkylation repair and the induction of cell death and sister chromatid exchange in human cells.
abstract: Mer- human cells, which lack O6-methylguanine DNA methyltransferase activity, are extremely sensitive to alkylation induced killing, mutation and sister chromatid exchange. We have analyzed a Mer+, a Mer-, and a Mer- revertant HeLa cell line and found that the methyltransferase deficiency correlates with increased levels of mutation and sister chromatid exchange, but does not correlate with increased killing of Mer- HeLa cells by alkylating agents. Furthermore, we show that HeLa Mer- cells repair N-3-methylguanine and N-3-methyladenine just as efficiently as HeLa Mer+ cells.
mesh_terms: D000225:Adenine / Q000031:analogs & derivatives / Q000378:metabolism; D000477:Alkylating Agents / Q000633:toxicity*; D000478:Alkylation; D002470:Cell Survival; D004260:DNA Repair; D006147:Guanine / Q000031:analogs & derivatives / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D008769:Methylnitronitrosoguanidine / Q000633:toxicity; D011687:Purines; D012854:Sister Chromatid Exchange / Q000187:drug effects*
chemical_list: D000477:Alkylating Agents; D011687:Purines; D008769:Methylnitronitrosoguanidine; C044502:3-methylguanine; C025946:3-methyladenine; D006147:Guanine; C008449:O-(6)-methylguanine; D000225:Adenine