华中农业大学揭示高温介导害虫对杀虫剂敏感性变异机制

　　近日，华中农业大学植物科学技术学院农药毒理学及有害生物抗药性团队的研究进展在线发表，研究揭示了高温条件下褐飞虱对杀虫剂敏感性的变异机制，解析了共生菌调控宿主解毒代谢的信号通路，为全球变暖背景下害虫防治及农药的科学合理使用提供了重要的理论依据。

 

　　高温及抗生素抑制褐飞虱共生菌介导的解毒代谢

 

　　杀虫剂在保障全球范围内的粮食安全生产中发挥了重要作用，该研究团队前期研究发现新烟碱类杀虫剂对褐飞虱的毒力呈现出显著的正温度效应（Pesticide Biochemistry and Physiology, 2019, 156, 80-86）。基于该特性，该研究团队进一步以温度响应性聚合物修饰的中空介孔二氧化硅纳米复合物为载体材料巧妙设计制备了温度响应性纳米载药体系，该体系对褐飞虱的毒力与温度呈显著正相关，且较传统剂型具有更长的持效期，可显著提高杀虫剂利用率（Chemical Engineering Journal, 2020, 383, 123169）。然而，高温介导害虫杀虫剂敏感性变异的机制仍是未解之谜。

 

 

　　共生菌Wolbachia调控褐飞虱解毒代谢

 

　　研究发现，高温胁迫可显著抑制褐飞虱温度敏感性共生菌，进而抑制褐飞虱解毒代谢酶基因的表达，破坏共生菌介导宿主的解毒代谢。分子机制上的研究进一步揭示了温度敏感性共生菌可通过宿主CncC信号通路对褐飞虱解毒代谢酶基因表达的调控。该研究明确了温度敏感性共生菌沃尔巴克氏体（Wolbachia）在调控褐飞虱解毒代谢中的重要作用，阐明了高温导致褐飞虱杀虫剂敏感性变异机制。深入了解昆虫共生菌调控宿主杀虫剂解毒代谢的机制有助于建立杀虫剂抗性协同进化的模型，推动害虫抗药性高效管理策略的制定，并为“靶菌治虫”策略的实施奠定了重要基础。

 

　　研究成果以“Decline in symbiont-dependent host detoxification metabolism contributes to increased insecticide susceptibility of insects under high temperature”为题在The ISME Journal发表。植物科学技术学院农药学专业博士研究生张云骅为论文第一作者，万虎副教授和美国弗罗里达大学的Adam C. N. Wong助理教授为论文的共同通讯作者，李建洪教授参与了项目的指导，何顺副教授参与了研究，上述研究得到国家自然科学基金、国家重点研发计划、湖北省自然科学基金、校自主创新基金等项目的资助。

 

　　【英文摘要】

 

　　The interactions between insects and their bacterial symbionts are shaped by a variety of abiotic factors, including temperature. As global temperatures continue to break high records, a great deal of uncertainty surrounds how agriculturally important insect pests and their symbionts may be affected by elevated temperatures, and its implications for future pest management. In this study, we examine the role of bacterial symbionts in the brown planthopper Nilaparvata lugens response to insecticide （imidacloprid） under different temperature scenarios. Our results reveal that the bacterial symbionts orchestrate host detoxification metabolism via the CncC pathway to promote host insecticide resistance, whereby the symbiont-inducible CncC pathway acts as a signaling conduit between exogenous abiotic stimuli and host metabolism. However, this insect-bacterial partnership function is vulnerable to high temperature, which causes a significant decline in host-bacterial content. In particular, we have identified the temperature-sensitive Wolbachia as a candidate player in N. lugens detoxification metabolism. Wolbachia-dependent insecticide resistance was confirmed through a series of insecticide assays and experiments comparing Wolbachia-free and Wolbachia-infected N. lugens and also Drosophila melanogaster. Together, our research reveals elevated temperatures negatively impact insect-bacterial symbiosis, triggering adverse consequences on host response to insecticide （imidacloprid） and potentially other xenobiotics.

 

　　论文链接：

 

　　https://www.nature.com/articles/s41396-021-01046-1