title: Expression and induction of three family 4 cytochrome P450 (CYP4)* genes identified from insecticide-resistant and susceptible western corn rootworms, Diabrotica virgifera virgifera.
abstract: We have previously determined that cytochrome P450-based oxidation is involved in resistance to the insecticides methyl parathion and carbaryl in geographically distinct Nebraska western corn rootworm populations. Three new family 4 cytochrome P450 (CYP4) gene fragments (CYP4AJ1, CYP4G18 and CYP4AK1) were cloned and sequenced from insecticide-resistant and -susceptible western corn rootworms. Insecticide bioassays indicated the resistant population employed in this study was significantly resistant to the insecticides methyl parathion and carbaryl. CYP4AJ1 and CYP4G18 were cloned from both genomic PCR and RT-PCR products, although only CYP4AJ1 contains an intronic region. Alignments of inferred amino acid sequences with other homologous insect CYP4 genes indicates a high degree of similarity. Northern analysis concurrently employing mixed probes representing each of the three rootworm CYP4 fragments identified increased mRNA transcript signals (i) in resistant rootworms and (ii) following induction by the P450 inducer pentamethyl benzene. These results support our previous documentation of P450-based insecticide resistance and suggest increased CYP4 transcript abundance can serve as a molecular resistance-associated marker.
authors: Department of Entomology, 202 Plant Industry, University of Nebraska, Lincoln, NE 68583-0816, USA.
authors: M E
authors: ME
authors: Scharf
authors: S
authors: S
authors: Parimi
authors: L J
authors: LJ
authors: Meinke
authors: L D
authors: LD
authors: Chandler
authors: B D
authors: BD
authors: Siegfried
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D001681:Biological Assay; D001517:Coleoptera / Q000201:enzymology* / Q000235:genetics; D003577:Cytochrome P-450 Enzyme System / Q000235:genetics*; D018076:DNA, Complementary; D015870:Gene Expression; D007305:Insecticide Resistance / Q000235:genetics; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction / Q000379:methods; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D018076:DNA, Complementary; D003577:Cytochrome P-450 Enzyme System; C434941:cytochrome P-450 CYP4AJ1 (corn rootworm); C434943:cytochrome P-450 CYP4AK1 (corn rootworm); C434942:cytochrome P-450 CYP4G18 (corn rootworm)