The Fat Body-Specific GST Gene <i>SlGSTe11</i> Enhances the Tolerance of <i>Spodoptera litura</i> to Cyantraniliprole and Nicotine

<i>Spodoptera litura</i> is a significant agricultural pest, and its glutathione <i>S</i>-transferase (GST) plays a crucial role in insecticide resistance. This study aimed to investigate the relationship between the <i>SlGSTe11</i> gene of <i>S. litura</i> and resistance to cyantraniliprole and nicotine. Transcriptome analysis revealed that <i>SlGSTe11</i> is highly expressed mainly in fat bodies, with a significant increase in <i>SlGSTe11</i> gene expression under induction by cyantraniliprole and nicotine. The ectopic expression of the <i>SlGSTe11</i> gene in transgenic fruit flies resulted in a 5.22-fold increase in the tolerance to cyantraniliprole. Moreover, compared to the UAS-<i>SlGSTe11</i> line, the Act5C-UAS><i>SlGSTe11</i> line laid more eggs and had a lower mortality after nicotine exposure. RNAi-mediated inhibition of <i>SlGSTe11</i> gene expression led to a significant increase in the mortality of <i>S. litura</i> under cyantraniliprole exposure. <i>In vitro</i> metabolism experiments demonstrated that the recombinant <i>SlGSTe11</i> protein efficiently metabolizes cyantraniliprole. Molecular docking results indicated that <i>SlGSTe11</i> has a strong affinity for both cyantraniliprole and nicotine. These findings suggest that <i>SlGSTe11</i> is involved in the development of resistance to cyantraniliprole and nicotine in <i>S. litura</i>.