Sex-specific expression of detoxification proteins contributes to differential metabolic detoxification capacity and acaricide sensitivity in female and male Tetranychus cinnabarinus (Boisduval).

Pronounced sex-specific differences exist in the toxicological traits of spider mite species. Our previous work showed that female Tetranychus cinnabarinus exhibit significantly higher tolerance to acaricides than males, primarily driven by elevated detoxification enzyme activity. However, the molecular basis underlying this sex-specific difference remains unclear. Here, we used pyridaben and cyflumetofen as representative acaricides to dissect the molecular mechanisms underlying sex-specific differences in detoxification metabolism between female and male mites. After 48 h of cyflumetofen exposure, GST activity increased significantly in female mites. Following pyridaben exposure, the activities of both P450 (24 h and 48 h) and CCE (48 h) increased significantly in female mites. Under the same conditions, only P450 activity increased significantly in male mites after 48 h of pyridaben exposure. Proteomic profiling identified 33 differentially expressed detoxification enzymes, predominantly from the major detoxification families P450, GST, and CCE; among them, 26 were significantly upregulated in females relative to males. Six detoxification enzymes, including CYP392A3, CYP389C5, TcGSTd02, TcGSTd13, TcCCE39, and TcCCE52, were selected for functional characterization. We successfully obtained six active recombinant detoxification enzymes through heterologous expression. IC50 and in vitro metabolism assays showed that these recombinant proteins display both shared and distinct capacities for metabolizing or sequestering cyflumetofen and pyridaben. RNAi and bioassay results demonstrated that silencing CYP389C5, TcGSTd02, and TcCCE52 resulted in more pronounced changes in acaricide susceptibility in female than in male mites. Collectively, this study demonstrates that the sex-biased protein abundance identifies candidate biochemical contributors to differential susceptibility in female and male mites.