A Drosophila simulans mutant strain sensitive to benzo[a]pyrene and 2-acetylaminofluorene

We have identified a Drosophila simulans mutant, 364 yv, that is sensitive to the toxic effects of the procarcinogens B(a)P and 2-AAF. Heterozygotes obtained by crossing it to the wild resistant Turku strain (♀ 364 yv × ♂ Turku) were more sensitive than heterozygotes obtained from the reciprocal cross (♀ Turku × ♂ 364yv) to both the toxic and the mutagenic effects of B(a)P in Drosophila tests that measured lethality and the induction of somatic mosaicism, respectively. The non-carcinogens pyrene, B(e)P and 4-AAF were only weakly toxic and non-mutagenic. In the Ames test B(a)P activation with S15 fractions prepared from the homogenates of Drosophila larvae and imagoes of the 364yv strain, as well as of the more resistant D. melanogaster y ++/+w sn³ heterozygotes, did not significantly increase the number of S. typhimurium TA100 revertants even following pretreatment with inducers of microsomal monooxygenases (B(a)P, PCB, PB). As for 2-AAF, a certain increase was observed following only PB, but not B(a)P pretreatment. Possible mechanisms of B(a)P and 2-AAF sensitivity of the 364yv strain, and perspectives on using it for monitoring genotoxic environmental pollutants, are discussed.