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

As a global pest, <i>Spodoptera litura</i> 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 <i>S. litura</i> genome database (ASM270686v3), and their expression patterns were analyzed through transcriptome analysis. Three candidate SLC genes with inducible expression characteristics in different tissues, namely, <i>SLC22A5</i>, <i>SLC52A3</i>, and <i>SLC12A4</i>, were selected for further experimental studies. The quantitative real-time polymerase chain reaction results indicated that following exposure to xenobiotics, <i>SLC52A3</i> was expressed in both the midgut and Malpighian tubules, <i>SLC22A5</i> expression was induced in the Malpighian tubules, and <i>SLC12A4</i> was expressed in the midgut. Overexpression of <i>SLC22A5</i>, <i>SLC52A3</i>, and <i>SLC12A4</i> in transgenic <i>Drosophila</i> conferred tolerance to xenobiotics. Furthermore, following the knockdown of <i>SLC52A3</i> via RNA interference, the tolerance of <i>S. litura</i> to both cyantraniliprole and chlorantraniliprole significantly decreased. These results suggest that SLC genes may play roles in driving the development of xenobiotic tolerance in <i>S. litura</i>.