title: Differential expression and induction of two Drosophila cytochrome P450 genes near the Rst(2)DDT locus.
abstract: Previous studies have shown that the major metabolic resistance locus in the insecticide-resistant Drosophila line Rst(2)DDT(Wisconsin) maps between the markers cn and vg on chromosome 2. Six cytochrome P450 genes exist in this region. We investigated the expression levels of these P450 genes in DDT-resistant and -susceptible fly lines. We report: (i) DDT resistance is significant (> 30-fold) and dominant, (ii) resistance is reduced by the cytochrome P450 inhibitor PBO, (iii) there is constitutive over-expression relative to susceptible flies of two genes encoding cytochrome P450 enzymes within the cn-vg region (CYP6G1 = 4.3-fold; CYP12D1 = 6.0-fold), and (iv) exposure to DDT results in an increased expression of only one of these two P450 genes (CYP12D1 > or = 6-fold above constitutive resistant fly baselines).
authors.affiliation: Department of Entomology, Room 100, 1158 Smith Hall, Purdue University, West Lafayette, IN 47907-1158, USA.
authors.forename: A
authors.initials: A
authors.lastname: Brandt
authors.forename: M
authors.initials: M
authors.lastname: Scharf
authors.forename: J H F
authors.initials: JH
authors.lastname: Pedra
authors.forename: G
authors.initials: G
authors.lastname: Holmes
authors.forename: A
authors.initials: A
authors.lastname: Dean
authors.forename: M
authors.initials: M
authors.lastname: Kreitman
authors.forename: B R
authors.initials: BR
authors.lastname: Pittendrigh
mesh_terms: D000818:Animals; D015152:Blotting, Northern; D065607:Cytochrome P-450 Enzyme Inhibitors; D003577:Cytochrome P-450 Enzyme System / Q000096:biosynthesis* / Q000235:genetics / Q000378:metabolism; D003634:DDT; D004247:DNA / Q000737:chemistry / Q000235:genetics; D004330:Drosophila / Q000201:enzymology* / Q000235:genetics / Q000378:metabolism; D004790:Enzyme Induction; D004791:Enzyme Inhibitors / Q000494:pharmacology; D015971:Gene Expression Regulation, Enzymologic / Q000235:genetics*; D007305:Insecticide Resistance / Q000235:genetics; D010574:Pesticide Synergists; D010882:Piperonyl Butoxide / Q000494:pharmacology; D016133:Polymerase Chain Reaction
chemical_list: D065607:Cytochrome P-450 Enzyme Inhibitors; D004791:Enzyme Inhibitors; D010574:Pesticide Synergists; D004247:DNA; D003577:Cytochrome P-450 Enzyme System; D003634:DDT; D010882:Piperonyl Butoxide