Induction of ouabain-resistant mutations in C3H 10T1/2 mouse cells by ultraviolet light.

Abstract

Ouabain-resistant mutants were induced in C3H mouse embryo 10T1/2 fibroblasts by exposure to UV light, thus making available an in vitro system for studying mutagenesis and oncogenic transformation in parallel. 86Rb uptake studies showed that biochemical mutants at the plasma membrane Na+, K+ transport ATPase (EC 3.6.1.3) locus were being selected for in this system. The optimal expression time for the mutants depended on the dose of UV light, as was the induced mutation frequency. The ratio of transformation to mutation frequencies was on the order of 10 for 4 doses, suggesting that the target size in the cellular genome for transformation may be approximately 10 times the size of the Na+, K+ ATPase gene. Transformation and mutation induction may be quantitatively studied in this single system.