Fatty acid synthase regulates lipid metabolism in Panonychus citri (McGregor) (Acari: Tetranychidae) and its potential for mite control

Fatty acid synthase (FAS) is a vital enzyme required for synthesis of unsaturated fatty acids which play important roles in many physiological processes. However, the function of FAS in lipid metabolism and reproduction of Panonychus citri adult female, and its potential for mite control remain unclear. In this study, the complementary DNA (cDNA) of PcFAS was obtained which contained nine conservative functional domains. The highest expression level of PcFAS was in adult female. RNA interference silencing of PcFAS in adult females resulted in a lethal phenotype, extended the developmental time and increased mortality. Additionally, FAS knockdown was revealed to significantly down-regulate FAS activity, total free fatty acid and triglyceride levels. Furthermore, the results of lipidomics analysis of P. citri after knockdown of PcFAS revealed that 40 lipid subclasses and 1012 lipid moleculars were identified and the main enriched pathways of differential lipid metabolites were focused on fat digestion and absorption, vitamin digestion and absorption, regulation of lipolysis in adipocytes and cholesterol metabolism. Conclusively, this study not only reveals the pivotal function of FAS in fatty acid metabolism, survival and reproduction of P. citri adult female, but also provides a novel target for control of citrus spider mite driven by lipid metabolism with biorational insecticide. © 2025 Society of Chemical Industry.