<i>CYP6DW3</i> Metabolizes Imidacloprid to Imidacloprid-urea in Whitefly (<i>Bemisia tabaci</i>)

Abstract

<i>Bemisia tabaci</i> has developed high resistance to many insecticides and causes substantial agricultural and economic losses annually. The insecticide resistance of whitefly has been widely reported in previous studies; however, the underlying mechanism remains little known. In this study, we cloned two P450 genes: <i>CYP6DW3</i> and <i>CYP6DW5v1;</i> these genes were markedly overexpressed in imidacloprid-resistant whitefly populations compared with susceptible populations, and knockdown of these genes decreased the imidacloprid resistance of whitefly. Moreover, heterologous expression of whitefly P450 genes in SF9 cells and metabolic studies showed that the <i>CYP6DW3</i> protein could metabolize 14.11% imidacloprid and produced imidacloprid-urea <i>in vitro</i>. Collectively, the expression levels of <i>CYP6DW3</i> and <i>CYP6DW5v1</i> are positively correlated with imidacloprid resistance in <i>B. tabaci</i>. Our study further reveals that cytochrome P450 enzymes affect the physiological activities related to resistance in insects, which helps scholars more deeply understand the resistance mechanism, and contributes to the development of integrated pest management framework.