ASSESSMENT OF GENOTOXICITY OF THE MYCOTOXIN PAXILLINE USING THE SOMATIC MUTATION AND RECOMBINATION TEST IN Drosophila melanogaster

In this study, we have evaluated the possible genotoxicity of paxilline using the somatic mutation and recombination test (SMART) in Drosophila melanogaster. Thirdinstar larvae were used, being trans-heterozygous for the two recessive markers located on the left arm of chromosome 3, multiple wing hairs (mwh) in map position 0.0 and flare-3 (flr3) at 39.0, while the centromere is located in position 47.7. These larvae were fed chronically with different concentrations of paxilline, and positive as well as negative controls were used to accomplish this purpose. SMART is based on the loss of heterozygosity which may occur through various mechanisms, such as mitotic recombination, mutation, deletion, half-translocation, chromosome loss and non-disjunction. Genetic changes occurring in somatic cells of the wing's imaginal discs cause the formation of mutant clones on the wing blade. Deletion, point mutation and nondisjunction induce single spots (small and large ones). Mitotic recombination induces both single spots and twin spots. According to the results obtained from this study, paxilline has a genotoxic effect in concentrations of >= 2 mu M.