Fatty acid-binding proteins (FABPs) are a family of lipid chaperones, which contribute to systemic metabolic regulation through diverse lipid signalings. In this study, a midgut-specific FABP gene (Slfabp2) was cloned from Spodoptera litura. RT-PCR and Western blot analysis indicated that RNA and protein levels of SlFABP2 gradually increased and reached a peak at the prepupal stage and maintained a high level during the pupal stage. The expression of SlFABP2 protein was induced by starvation treatment. In vitro binding assay revealed that the recombinant SlFABP2 had high affinities of binding long-chain fatty acids, such as palmitic acid, arachidonate and oleic acid. The results suggest that SlFABP2 may have a unique function that transports intracellular fatty acids and can regulate the metabolism of lipids in metamorphosis. This work provides experimental clues for understanding the potential function of SlFABP2 in fatty acid metabolism in S. litura.

脂肪酸结合蛋白（FABP）是脂质分子伴侣的一个家族，它们通过多种脂质信号传导促进系统性代谢调节。在这项研究中，从斜纹夜蛾（Spodoptera litura）克隆了中肠特异性FABP基因（Slfabp2）。RT-PCR和蛋白质印迹分析表明，SlFABP2的RNA和蛋白质水平逐渐增加，并在pu前阶段达到峰值，并在the阶段维持高水平。的表达S1中FABP2蛋白诱导饥饿处理。体外结合测定显示重组S1FABP2具有结合长链脂肪酸如棕榈酸，花生四烯酸酯和油酸的高亲和力。结果表明SlFABP2可能具有运输细胞内脂肪酸的独特功能，并且可以调节变态过程中脂质的代谢。这项工作为理解SlFABP2在斜纹夜蛾脂肪酸代谢中的潜在功能提供了实验线索。