稻飞虱迁飞调控对地磁强度变化的磁响应机制研究

Many insects can use magnetoreception to gain the orientation or location information from the geomagnetic field (GMF). In addition, it has not been clear until now whether GMF could affect other life activities of insects. Recently, the applicant found that physiological and behavioral phenotypes for migratory regulation of the nocturnally migratory brown planthopper, Nilaparvata lugens and white-backed planthopper, Sogatella furcifera responded significantly to changes in GMF intensity, which indicated the existence of the strategy for magnetic response in migratory regulation. In this project, based on the migration pattern of rice planthoppers, we will make use of artificial magnetic field for the simulation of changes in GMF intensity, and five crucial parts in regulation of rice planthopper migration including wing development, energy intake, reproductive regulation, phototaxis and flight behavior will be studied. The phenotypes, genes and signaling pathways responding significantly to changes in GMF intensity will be explored first. Then, patterns of Cryptochromes and MagR in regulating the phenotypes, downstream genes and signaling pathways found above will be analyzed with the RNAi technique. Finally, combined with the way how Cryptochromes and MagR work based on the immunological technique, we aim to further reveal the magnetic response mechanism for migratory regulation of rice planthopper to changes in GMF intensity. Through this project, it will perfect the migratory biology as well as make a contribution for the forecast of the occurrences and field control of rice planthopper. Moreover, the study will play a positive role in promoting the uncovering of fining magnetoreception mechanisms for migratory insects.

许多昆虫可利用磁感受能力从地磁场获取定向定位信息，此外，尚不明确地磁场是否可影响昆虫其他生命活动。申请人近期研究发现，水稻夜间迁飞性重大害虫褐飞虱和白背飞虱的迁飞调控生理、行为表型对地磁强度变化响应显著，反映出稻飞虱可能具备迁飞调控的磁响应策略。本项目拟依据稻飞虱迁飞规律，以人工磁场模拟其迁飞路径所涉及的地磁强度变化，围绕稻飞虱翅的发育、能源摄取、生殖调控、趋光与飞行行为五个迁飞调控关键环节：首先开展磁响应表型探究及磁响应基因、信号通路的生物信息学挖掘；然后利用RNAi技术分析稻飞虱磁感受关键基因（隐花色素和磁受体基因）对所发现磁响应表型及相关基因、信号通路的调控模式；最后结合免疫学技术明确磁感受关键蛋白的作用方式，深入解析稻飞虱迁飞调控对地磁强度变化的磁响应机制。本研究将完善稻飞虱迁飞生物学，服务于稻飞虱迁飞测报及稻田防控，并将对进一步揭示迁飞昆虫的磁感受机理起到积极促进作用。

许多昆虫可利用磁感受能力从地磁场获取定向定位信息。本团队前期研究反映出稻飞虱可能具备迁飞调控的磁响应策略。本项目依据稻飞虱迁飞规律，人工模拟地磁强度变化，围绕稻飞虱翅的发育、能源摄取、生殖调控、趋光与飞行五个迁飞调控关键环节：首先开展了稻飞虱迁飞调控对地磁强度变化的磁响应表型研究，发现稻飞虱的翅型分化、能源摄取、生殖调控、趋光行为和飞行行为均可特异性响应磁场强度变化，证明了地磁场对稻飞虱迁飞调控的重要作用；其次，利用转录组测序结合RNAi技术开展了磁响应基因及信号通路初步挖掘，发现仅5μT的差异即可引起134个基因显著性差异表达，并发现敲减磁感受关键基因MagR可显著影响与褐飞虱生殖相关的信号通路，进一步发现隐花色素（Cryptochromes, Crys）、类胰岛素通路、神经肽和激脂激素通路可能参与了以Crys为上游磁感受基因的磁响应信号转导；随后，基于RNAi技术，以寿命为磁响应表型开展了稻飞虱上游磁感受关键基因功能研究，并以趋光性为磁响应表型开展了下游磁响应基因功能研究，研究发现Crys和MagR或参与磁感受过程，共济蛋白同源基因（Frataxin homolog，FH）或参与和趋光性相关的下游磁响应信号通路；最后，结合RNAi和qRT-PCR技术探究了磁感受关键基因Cry1，Cry2和MagR之间的潜在互作，结合免疫学技术明确了稻飞虱磁感受关键蛋白Cry1和MagR在复眼中的分布，并以帝王蝶为迁飞模式昆虫进一步佐证了Cry1在复眼和触角中的高转录和蛋白水平分布。综上，本项目进一步佐证并完善了本团队前期提出的“基于Crys介导的激素信号转导的磁响应”，深入探讨了稻飞虱迁飞调控对地磁强度变化的磁响应机制。本项目的开展完善了稻飞虱迁飞生物学，并将最终服务于稻飞虱迁飞测报及稻田防控。