Luo Qiaozhi, Mao Jianjun, Li Yuyan, Wang Mengqing, Zhang Lisheng, Shen Zhongjian
State Key Laboratory for Biology of Plant Diseases and Insect Pests, Key Laboratory of Natural Enemy Insects of Ministry of Agriculture and Rural Affairs, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China.
Key Laboratory of Animal Biosafety Risk Prevention and Control (North) of Ministry of Agriculture and Rural Affairs, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, China.
Insect Mol Biol. 2025 Feb;34(1):218-227. doi: 10.1111/imb.12964. Epub 2024 Oct 23.
Protein disulphide isomerase (PDI) possesses disulphide isomerase, oxidoreductase and molecular chaperone activities, and is involved in regulating various physiological processes. However, there are few studies on the function in insect diapause. In this study, we cloned one novel member PDI family (TMX3, thioredoxin-related transmembrane protein 3) in Arma chinensis. The AcTMX3 encodes 426 amino acids that contains a predicted N-terminal signal sequence, a thioredoxin-like domain with the CXXC active site and a potential transmembrane region, which are typical sequence features of TMX3. RT-qPCR results showed that AcTMX3 was mainly expressed in the head under non-diapause conditions, while AcTMX3 was highly expressed in the fat body (central metabolic organ) under diapause conditions. Moreover, temporal expression profile showed that compared with non-diapause conditions, diapause conditions significantly induced AcTMX3 expression, and the expression of AcTMX3 was enhanced at 15°C. Silencing AcTMX3 in A. chinensis significantly inhibited the expression of antioxidant genes (AcTrx2 and AcTrx-like), increased the content of HO and ascorbate and reduced the survival rate of A. chinensis under diapause conditions. Our results suggested that AcTMX3 played an important role in the resistance of A. chinensis to oxidative stress under diapause conditions.
蛋白质二硫键异构酶（PDI）具有二硫键异构酶、氧化还原酶和分子伴侣活性，并参与调节各种生理过程。然而，关于其在昆虫滞育中的功能研究较少。在本研究中，我们克隆了中华大刀螳中一个新的PDI家族成员（TMX3，硫氧还蛋白相关跨膜蛋白3）。AcTMX3编码426个氨基酸，包含一个预测的N端信号序列、一个具有CXXC活性位点的硫氧还蛋白样结构域和一个潜在的跨膜区域，这些都是TMX3的典型序列特征。RT-qPCR结果显示，在非滞育条件下，AcTMX3主要在头部表达，而在滞育条件下，AcTMX3在脂肪体（中央代谢器官）中高表达。此外，时间表达谱显示，与非滞育条件相比，滞育条件显著诱导AcTMX3表达，且在15°C时AcTMX3的表达增强。在中华大刀螳中沉默AcTMX3显著抑制了抗氧化基因（AcTrx2和AcTrx样）的表达，增加了HO和抗坏血酸的含量，并降低了滞育条件下中华大刀螳的存活率。我们的结果表明，AcTMX3在滞育条件下中华大刀螳对氧化应激的抗性中起重要作用。
