title: DNA base sequence changes induced by ethyl methanesulfonate in a chromosomally integrated shuttle vector gene in mouse cells.
abstract: We have analyzed the specificity of mutations induced by ethyl methanesulfonate (EtMes) in mouse cells carrying a selectable bacterial gene. The target gene was the Escherichia coli gpt gene contained within a retroviral shuttle vector integrated into mouse chromosomal DNA. Following mutagenesis by EtMes, cells with mutations in the gpt gene were selected as resistant to 6-thioguanine. Shuttle vector sequences were recovered from the mutant cell lines following fusion with monkey COS cells and introduced into bacteria as part of a bacterial plasmid. The DNA base sequences of the mutant genes were directly determined from plasmid DNA. All of the EtMes-induced mutations involving single base changes were found to be G:C to A:T transitions.
authors.affiliation: Center for Genetics, University of Illinois College of Medicine, Chicago 60612.
authors.forename: C R
authors.initials: CR
authors.lastname: Ashman
authors.forename: R L
authors.initials: RL
authors.lastname: Davidson
mesh_terms: D000818:Animals; D001483:Base Sequence; D002460:Cell Line; D004247:DNA / Q000235:genetics*; D004926:Escherichia coli / Q000235:genetics; D005020:Ethyl Methanesulfonate / Q000633:toxicity*; D005798:Genes, Bacterial; D005814:Genes, Viral; D005822:Genetic Vectors; D051379:Mice; D009154:Mutation; D010957:Plasmids; D012190:Retroviridae / Q000235:genetics
chemical_list: D004247:DNA; D005020:Ethyl Methanesulfonate