Activation of the ROS/CncC Pathway Regulates Cytochrome P450 to Confer Cycloxaprid Tolerance in .

The inducible P450 gene plays a key role in the response of insects to insecticide stress. However, the transcriptional regulatory mechanism of insecticide-inducible detoxification enzyme genes has not been well clarified. In the present study, a P450 gene, , could be induced by cycloxaprid in both susceptible and cycloxaprid-resistant strains. RNA interference (RNAi) and transgenic results showed that this P450 gene contributes to cycloxaprid tolerance. Moreover, the results of RNAi, dual-luciferase reporter, and yeast one-hybrid assays verified that is regulated by the transcription factor . In addition, although exposure to cycloxaprid resulted in the accumulation of ROS in both susceptible and cycloxaprid-resistant strains, treatment of melon aphids with NAC reduced ROS levels and decreased and expression. These findings suggest that cycloxaprid-induced ROS accumulation activates the CncC pathway, leading to the upregulated expression of and enhancement of cycloxaprid tolerance in melon aphids. These results deepened our understanding of the regulatory mechanism of insecticide-induced detoxification enzyme gene upregulation in insects.