Cd Exposure Confers Cross-Tolerance of Larvae to β-Cypermethrin through miRNA-Mediated Post-Transcriptional Regulation.

Heavy metals are prevalent environmental contaminants in pest habitats. This study investigates the tolerance of larvae to β-cypermethrin under cadmium (Cd) stress. Exposure to Cd markedly enhanced larval tolerance to β-cypermethrin. The P450 enzyme was found to be crucial in triggering this cross-tolerance. Notably, Cd exposure significantly upregulated the expression of and both before and after β-cypermethrin treatment. Silencing these genes reduced the β-cypermethrin tolerance in Cd-exposed larvae. Furthermore, overexpression of and significantly improved the tolerance of 9 cells and to β-cypermethrin. Silencing of , a key gene in the miRNA synthesis pathway, significantly diminished the β-cypermethrin tolerance in Cd-treated larvae. The miR-2739 controlled overexpression of , while miR-2854 controlled overexpression, both of which were essential for β-cypermethrin cross-tolerance in larvae under Cd exposure. Collectively, Cd exposure induces cross-tolerance to β-cypermethrin in larvae through miRNA-mediated post-transcriptional regulation.