Hsp70 and Hsp90 Elaborately Regulate RNAi Efficiency in .

Heat-shock proteins (HSPs) serve as molecular chaperones in the RNA interference (RNAi) pathway of eukaryotic organisms. In model organisms, Hsp70 and Hsp90 facilitate the folding and remodeling of the client protein Argonaute (Ago). However, the specific function of HSPs in the RNAi pathway of (L.) (Lepidoptera: Plutellidae) remains unknown. In this study, we identified and analyzed the coding sequences of and (also known as ). Both PxHsc70-4 and PxHsp83 exhibited three conserved domains that covered a massive portion of their respective regions. The knockdown or inhibition of and in vitro resulted in a significant increase in the gene expression of the dsRNA-silenced reporter gene , leading to a decrease in its RNAi efficiency. Interestingly, the overexpression of PxHsc70-4 and PxHsp83 in DBM, Sf9, and S2 cells resulted in an increase in the bioluminescent activity of dsRNA-silenced luciferase, indicating a decrease in its RNAi efficiency via the overexpression of Hsp70/Hsp90. Furthermore, the inhibition of and in vivo resulted in a significant increase in the gene expression of . These findings demonstrated the essential involvement of a specific quantity of Hsc70-4 and Hsp83 in the siRNA pathway in . Our study offers novel insights into the roles played by HSPs in the siRNA pathway in lepidopteran insects.