Overexpression of cytochrome P450 CYP6BG1 may contribute to chlorantraniliprole resistance in Plutella xylostella (L.)

• Published in: Pest management science Vol. 74; no. 6; pp. 1386 - 1393
• Main Authors: Li, Xiuxia, Li, Ran, Zhu, Bin, Gao, Xiwu, Liang, Pei
• Format: Journal Article
• Language: English
• Published: Chichester, UK John Wiley & Sons, Ltd 01.06.2018; Wiley Subscription Services, Inc
• Subjects: Butterflies & moths; chlorantraniliprole; crops; CYP6BG1; Cytochrome; cytochrome P-450; Cytochrome P450; Detoxification; double-stranded RNA; Drosophila melanogaster; Enzymatic activity; enzyme activity; Fruit flies; Gene expression; genes; insect pests; Insecticide resistance; Insecticides; Metabolism; Mutation; Pests; Plutella xylostella; Ribonucleic acid; RNA; RNA interference; RNA-mediated interference; Toxicity; transgenic fruit fly; transgenic insects; CYP6BG1; Plutella xylostella; transgenic fruit fly; insecticide resistance; chlorantraniliprole
• ISSN: 1526-498X; 1526-4998; 1526-4998
• DOI: 10.1002/ps.4816

BACKGROUND The diamondback moth Plutella xylostella (L.) is the most widely distributed pest of cruciferous crops and has developed resistance to most commonly used insecticides, including chlorantraniliprole. Resistance to chlorantraniliprole is likely caused by mutations of the target, the ryanodine receptor, and/or mediated by an increase in detoxification enzyme activities. Although target‐site resistance is documented in detail, resistance mediated by increased metabolism has rarely been reported. RESULTS The activity of cytochrome P450 was significantly higher in two resistant P. xylostella populations than in a susceptible one. Among ten detected cytochrome P450 genes, CYP6BG1 was significantly overexpressed (over 80‐fold) in a field‐resistant population compared with expression in a susceptible one. Knockdown of CYP6BG1 by RNA interference dramatically reduced the 7‐ethoxycoumarin‐O‐deethylase (7‐ECOD) activity of P450 by 45.5% and increased the toxicity of chlorantraniliprole toward P. xylostella by 26.8% at 48 h postinjection of double‐stranded RNA. By contrast, overexpression of CYP6BG1 in a transgenic Drosophila melanogaster line significantly decreased the toxicity of the insecticide to the transgenic flies. CONCLUSIONS Overexpression of CYP6BG1 may contribute to chlorantraniliprole resistance in P. xylostella. Our findings will provide new insights into the mechanisms of resistance to diamide insecticides in other insect pests. © 2017 Society of Chemical Industry Knockdown of CYP6BG1 reduced the total P450 activity and increased the chlorantraniliprole toxicity to P. xylostella; overexpression of CYP6BG1 in D. melanogaster decreased the insecticide toxicity to the flies.