Identification and Functional Validation of the Role of Solute Carriers in Shaping Xenobiotic Tolerance in Polyphagous Pests of Spodoptera litura

As a global pest, Spodoptera litura causes significant economic losses annually, making it imperative to investigate its metabolic detoxification mechanisms. The solute carrier (SLC) gene constitutes a superfamily of genes that can directly or indirectly influence the metabolic detoxification functions of insects. In this study, 108 SLC genes were identified via the S. litura genome database (ASM270686v3), and their expression patterns were analyzed through transcriptome analysis. Three candidate SLC genes with inducible expression characteristics in different tissues, namely, SLC22A5, SLC52A3, and SLC12A4, were selected for further experimental studies. The quantitative real-time polymerase chain reaction results indicated that following exposure to xenobiotics, SLC52A3 was expressed in both the midgut and Malpighian tubules, SLC22A5 expression was induced in the Malpighian tubules, and SLC12A4 was expressed in the midgut. Overexpression of SLC22A5, SLC52A3, and SLC12A4 in transgenic Drosophila conferred tolerance to xenobiotics. Furthermore, following the knockdown of SLC52A3 via RNA interference, the tolerance of S. litura to both cyantraniliprole and chlorantraniliprole significantly decreased. These results suggest that SLC genes may play roles in driving the development of xenobiotic tolerance in S. litura.