title: Mutagenic treatments result in inactivation of expression of a transfected bacterial gene integrated into a human cell line.
abstract: The cell line E2 is a SV40-transformed human fibroblast cell line containing a single integrated copy of the bacterial guanine phosphoribosyl transferase (gpt) gene. Treatment of E2 with ultraviolet light (UV) or ethyl methanesulphonate (EMS) induced the formation of Gpt- derivatives. Several induced derivatives have been isolated, and the structure, expression and revertibility of the gpt gene have been analysed. In the majority of cases the Gpt- phenotype resulted from switching off the gpt gene, in most instances by methylation, but in a few cases by phenotypic switching. Thus mutagenic treatment can result in the inactivation of gene expression in human cells. In a small proportion of Gpt- derivatives the gpt sequences were deleted.
authors: MRC Cell Mutation Unit, University of Sussex, Brighton, Great Britain.
authors: A R
authors: AR
authors: Lehmann
authors: C F
authors: CF
authors: Arlett
authors: S A
authors: SA
authors: Harcourt
authors: H
authors: H
authors: Steingrimsdottir
authors: M M
authors: MM
authors: Gebara
mesh_terms: D001374:Azacitidine / Q000494:pharmacology; D015139:Blotting, Southern; D002460:Cell Line; D004260:DNA Repair; D005786:Gene Expression Regulation / Q000187:drug effects; D005798:Genes, Bacterial; D006801:Humans; D007041:Hypoxanthine Phosphoribosyltransferase; D008745:Methylation; D009152:Mutagenicity Tests / Q000379:methods*; D009153:Mutagens; D010430:Pentosyltransferases / Q000235:genetics*; D013866:Thioguanine / Q000633:toxicity; D014466:Ultraviolet Rays
chemical_list: D009153:Mutagens; D010430:Pentosyltransferases; D007041:Hypoxanthine Phosphoribosyltransferase; D013866:Thioguanine; D001374:Azacitidine