Key Laboratory of Entomology and Pest Control Engineering, College of Plant Protection, Southwest University, Chongqing 400715, China.
Key Laboratory of Entomology and Pest Control Engineering, College of Plant Protection, Southwest University, Chongqing 400715, China; Key Laboratory of Agricultural Biosafety and Green Production of Upper Yangtze River (Ministry of Education), Academy of Agricultural Sciences, Southwest University, Chongqing 400716, China.
Pestic Biochem Physiol. 2024 Feb;199:105763. doi: 10.1016/j.pestbp.2023.105763. Epub 2023 Dec 30.
The oriental fruit fly, Bactrocera dorsalis (Hendel), an invasive insect pest infesting fruits and vegetables, possesses a remarkable capacity for environmental adaptation. The investigation of behind mechanisms of the stress adaptability in B. dorsalis holds significantly practical relevance. Previous studies on the molecular mechanism underlying stress resistance in B. dorsalis have predominantly focused on nuclear-coding genes, with limited exploration on organelle-coding genes. In this study, we assessed alterations in the mitochondrial physiological parameters of B. dorsalis under exposure to malathion, avermectin, and beta-cypermethrin at LD dosages. The results showed that all three insecticides were capable of reducing mitochondrial complex IV activity and ATP content. Expression patterns of mitochondrial coding genes across different developmental stages, tissues and insecticide exposures were analyzed by RT-qPCR. The results revealed that these mitochondrial coding genes were expressed in various tissues and at different developmental stages. Particularly noteworthy, atp6, cox2, and cytb exhibited substantial up-regulation in response to malathion and avermectin treatment. Furthermore, RNAi-mediated knockdown of atp6 and cox2 resulted in the increased toxicity of malathion and avermectin against B. dorsalis, and cox2 silencing was also associated with the decreased complex IV activity. These findings suggest that atp6 and cox2 most likely play pivotal roles in mediating tolerance or resistance to malathion and avermectin in B. dorsalis. Our results provide novel insights into the role of mitochondrial coding genes in conferring tolerance to insecticides in B. dorsalis, with practical implications for controlling this pest in the field.
东方果实蝇，Bactrocera dorsalis（Hendel），一种侵袭水果和蔬菜的入侵昆虫害虫，具有非凡的环境适应能力。研究 B. dorsalis 应激适应性的背后机制具有重要的实际意义。以前关于 B. dorsalis 应激抗性的分子机制的研究主要集中在核编码基因上，对细胞器编码基因的研究有限。在这项研究中，我们评估了 LD 剂量下马拉硫磷、阿维菌素和β-氯氰菊酯暴露对 B. dorsalis 线粒体生理参数的影响。结果表明，这三种杀虫剂都能降低线粒体复合物 IV 活性和 ATP 含量。通过 RT-qPCR 分析了不同发育阶段、组织和杀虫剂暴露下线粒体编码基因的表达模式。结果表明，这些线粒体编码基因在不同组织和不同发育阶段都有表达。特别值得注意的是，atp6、cox2 和 cytb 在受到马拉硫磷和阿维菌素处理时表现出显著上调。此外，atp6 和 cox2 的 RNAi 介导敲低导致马拉硫磷和阿维菌素对 B. dorsalis 的毒性增加，cox2 沉默也与复合物 IV 活性降低有关。这些发现表明，atp6 和 cox2 很可能在介导 B. dorsalis 对马拉硫磷和阿维菌素的耐受性或抗性中发挥关键作用。我们的结果为线粒体编码基因在赋予 B. dorsalis 对杀虫剂的耐受性中的作用提供了新的见解，对田间控制这种害虫具有实际意义。
