【摘要】 谷胱甘肽-S-转移酶（Glutathione-S-transferases,GSTs）在昆虫适应植物次生代谢物质中发挥重要作用，为明确番茄潜叶蛾Tuta absoluta的GSTs基因在其响应α-番茄碱胁迫中的作用。本研究利用PCR技术克隆了番茄潜叶蛾TabsGSTs2基因全长，通过生物信息学方法分析了TabsGSTs2基因的序列特征、理化特性、保守结构域、基因结构和进化关系，通过RT-qPCR技术测定了α-番茄碱胁迫下TabsGSTs2基因的表达情况，利用同源建模和分子对接研究了TabsGSTs2和α-番茄碱的结合能力与结合模式。结果表明，TabsGSTs2基因的CDS全长为609 bp，编码203个氨基酸，理论等电点为8.47，分子量为23.895 kDa;TabsGSTs2具有4个β-折叠和9个α-螺旋，具有典型的GSTs保守结构域，包括GSH结合位点（G-site）和底物结合位点（H-site）;TabsGSTs2属于sigma亚家族成员，与苹果蠹蛾Cydia pomonella的CpGSTs2亲缘关系较近；α-番茄碱胁迫下，TabsGSTs2基因在72 h的表达量显著高于对照；TabsGSTs2与α-番茄碱的结合能力较强，主要以氢键、疏水作用力和盐桥等相互作用维持稳定的结合。研究结果可为后续研究番茄潜叶蛾适应α-番茄碱的分子机制提供参考，为进一步挖掘番茄潜叶蛾防控新靶标提供基础。更多还原

【Abstract】 Glutathione-S-transferases(GSTs) play an important role in insect adaptation to plant secondary metabolites. To clarify the role of the GST gene in the detoxification of Tuta absoluta to α-tomatine, we first cloned the full-length sequence of TabsGSTs2 gene. Bioinformatic analysis was employed to analyze the sequence characteristics, physicochemical properties, conserved domains, gene structure, and evolutionary relationships of the TabsGSTs2 gene. The expression levels of TabsGSTs2 under α-tomatine stress were measured using RT-qPCR, and the binding capacity and mode of TabsGSTs2 to α-tomatine were investigated using homology modeling and molecular docking. The results showed that the CDS of TabsGSTs2 was 609 bp, encoding 203 amino acids, with a theoretical isoelectric point of 8.47 and a molecular weight of 23.895 kDa. TabsGSTs2 contains four β-sheets and nine α-helices, and had the typical conserved domains of GST genes, including the GSH binding site(G-site) and the substrate binding site(Hsite). Phylogenetic analysis indicated that TabsGSTs2 belongs to the sigma subfamily and was closely related to CpGSTs2 of Cydia pomonella. Under α-tomatine stress, the expression level of TabsGSTs2 was significantly higher than that of the control at 72 h. Molecular docking results suggested that TabsGSTs2 bind strongly to α-tomatine, with the interaction being stabilized primarily by hydrogen bonds, hydrophobic forces, and salt bridges. Our study provides reference for subsequent studies of the molecular mechanisms of T. absoluta adaptation to α-tomatine and provides a basis for further exploration of new targets for the control of T. absoluta.更多还原