CYTOCHROME-P450 GENE CLUSTERS IN DROSOPHILA-MELANOGASTER

Twelve cytochrome P450 cDNA fragments were cloned from Drosophila mela nogaster by reverse transcriptase/PCR (RT/PCR) using degenerate oligon ucleotide primers. The corresponding genes belong to several subfamili es of the CYP4 and CYP9 P450 families. Only two of these genes, Cyp4d1 and Cyp4d2, have previously been described. In situ hybridization of each of the cDNA fragments showed two clusters of genes; one near the tip of the X chromosome and the other on the left arm of chromosome 2. Interestingly the latter cluster comprises widely divergent genes bel onging both to the CYP9 and CYP4 families and also to the CYP6 family (Cyp6a2). Putative allelic variants of several of the genes were found in different insecticide-resistant and -susceptible strains (Hikone R , Haag 79 and Oregon R). The identification of these genes and alleles will allow us to clarify the involvement of P450s in xenobiotic metab olism and will facilitate a genetic analysis of P450 functions in inse cts.