Overexpression of Multiple Cytochrome P450 Genes Conferring Clothianidin Resistance in .

Cytochrome P450 monooxygenases (P450s) play important roles in the detoxification metabolism of xenobiotics and are involved in the resistance of insects to many insecticides. In this study, piperonyl butoxide (PBO), an inhibitor of P450 enzyme activity, significantly increased the toxicity of clothianidin in the clothianidin-resistant (CL-R) population of . The enzyme activity of P450 in the CL-R population was significantly higher than that in the SS population. Furthermore, four P450 genes were found to be significantly overexpressed in the CL-R population. Tissue-specific expression analysis indicates that , , , and were most highly expressed in the midgut and/or Malpighian tubules. After exposure to LC of clothianidin, the expression levels of the four P450 genes were significantly upregulated. The RNAi-mediated knockdown of , , and significantly increased the susceptibility of to clothianidin. These results suggest that P450 genes are involved in clothianidin resistance in . This provides a better understanding of P450-mediated clothianidin resistance in and will contribute to the management of insect resistance to insecticides.