21929695

not annotated - annotated - LINNAEUS only

Overexpression of a cytochrome P450 monooxygenase, CYP6ER1, is associated with resistance to imidacloprid in the brown planthopper, Nilaparvata lugens.

The brown planthopper, Nilaparvata lugens, is an economically significant pest of rice throughout Asia and has evolved resistance to many insecticides including the neonicotinoid imidacloprid. The resistance of field populations of N. lugens to imidacloprid has been attributed to enhanced detoxification by cytochrome P450 monooxygenases (P450s), although, to date, the causative P450(s) has (have) not been identified. In the present study, biochemical assays using the model substrate 7-ethoxycoumarin showed enhanced P450 activity in several resistant N. lugens field strains when compared with a susceptible reference strain. Thirty three cDNA sequences encoding tentative unique P450s were identified from two recent sequencing projects and by degenerate PCR. The mRNA expression level of 32 of these was examined in susceptible, moderately resistant and highly resistant N. lugens strains using quantitative real-time PCR. A single P450 gene (CYP6ER1) was highly overexpressed in all resistant strains (up to 40-fold) and the level of expression observed in the different N. lugens strains was significantly correlated with the resistance phenotype. These results provide strong evidence for a role of CYP6ER1 in the resistance of N. lugens to imidacloprid.



Ann file

T1	Species 113 130	brown planthopper

N1 Reference T1 Taxonomy:108931

T2 Species 132 150 Nilaparvata lugens

N2 Reference T2 Taxonomy:108931

T3 Species 158 175 brown planthopper

N3 Reference T3 Taxonomy:108931

T4 Species 177 195 Nilaparvata lugens

N4 Reference T4 Taxonomy:108931

T5 Species 236 240 rice

N5 Reference T5 Taxonomy:4530

T6 Species 386 395 N. lugens

N6 Reference T6 Taxonomy:108931

T7 Species 710 719 N. lugens

N7 Reference T7 Taxonomy:108931

T8 Species 1032 1041 N. lugens

N8 Reference T8 Taxonomy:108931

T9 Species 1233 1242 N. lugens

N9 Reference T9 Taxonomy:108931

T10 Species 1392 1401 N. lugens

N10 Reference T10 Taxonomy:108931