title: Induction of forward mutations at the thymidine kinase locus of mouse lymphoma cells: evidence for electrophilic and non-electrophilic mechanisms.
abstract: A database of 209 chemicals tested for induction of forward mutations at the heterozygous thymidine kinase (TK +/-) locus in L5178Y mouse lymphoma cells was analyzed for structure-activity relationships using the MultiCASE expert system. Consistent with evidence of several contributing biological mechanisms, these studies suggest that such mutations may occur by more than one mechanism. As might be expected, there was evidence for a component involving direct electrophilic attack on the cellular DNA, in a manner previously established as causative in the induction of mutations in Salmonella. In addition, however, there was also strong evidence for another mechanism or mechanisms involving chromosome missegregation, cellular toxicity or an alternate site of action, such as the microtubules.
authors.affiliation: Department of Environmental and Occupational Health, University of Pittsburgh, PA 15238, USA.
authors.forename: B
authors.initials: B
authors.lastname: Henry
authors.forename: S G
authors.initials: SG
authors.lastname: Grant
authors.forename: G
authors.initials: G
authors.lastname: Klopman
authors.forename: H S
authors.initials: HS
authors.lastname: Rosenkranz
mesh_terms: D000818:Animals; D016208:Databases, Factual; D008223:Lymphoma / Q000201:enzymology*; D051379:Mice; D009152:Mutagenicity Tests; D009153:Mutagens / Q000737:chemistry / Q000633:toxicity; D009154:Mutation; D012486:Salmonella typhimurium / Q000235:genetics; D013329:Structure-Activity Relationship; D013937:Thymidine Kinase / Q000235:genetics*; D014407:Tumor Cells, Cultured
chemical_list: D009153:Mutagens; D013937:Thymidine Kinase