Propidium: Induction of petites and recovery from ethidium mutagenesis in [formula omitted][formula omitted

Abstract

It was shown that petite induction in growing cells of Saccharomyces cerevisiae by ethidium was strongly stimulated by the presence of propidium, a phenanthridinium dye of similar structure to ethidium. Propidium itself also induced petites in growing but not in resting cells. Furthermore, propidium could prevent petite induction in resting cells and caused recovery from ethidium induction with prolonged incubation. A possible mode of action of propidium in the ethidium-induced petite mutagenesis is discussed.