title: Elimination of MNU-induced mutational lesions in V79 Chinese hamster cells.
abstract: Studies were performed on the non-linear dose response for gene mutations induced by low doses of monofunctional methylating agents in V79 Chinese hamster cells. When treatment with methylnitrosourea was applied at the beginning of the S phase in synchronized cells, a linear dose-response curve was obtained, whereas application of the dose after gene replication resulted in a strong reduction of the number of induced mutations. Additional time for repair resulted in reduced dose response of MNU, indicating that an error-free repair process operates on methylated DNA in V79 Chinese hamster cells.
mesh_terms: D000818:Animals; D002453:Cell Cycle; D002478:Cells, Cultured; D006224:Cricetinae; D003412:Cricetulus; D004247:DNA / Q000378:metabolism; D004260:DNA Repair / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D004351:Drug Resistance; D008770:Methylnitrosourea / Q000494:pharmacology*; D009154:Mutation; D009607:Nitrosourea Compounds / Q000494:pharmacology*; D013866:Thioguanine / Q000494:pharmacology
chemical_list: D009607:Nitrosourea Compounds; D008770:Methylnitrosourea; D004247:DNA; D013866:Thioguanine