肠道细菌和中肠miRNA协同调控白纹伊蚊感染登革热病毒效率的机制研究

Aedes albopictus is among the most important vectors of arboviral diseases. With the rapid global expansion of Ae. albopictus, Dengue fever has became one of the most serious arboviruses worldwide. Recent studies indicated that midgut microbiota and microRNA (miRNA) of mosquitoes significantly affect development, digestion, metabolism, and immunity of their hosts. Midgut of Ae. albopictus is the first line of defense infection, replication and dissemination of dengue virus. However, there still lack of research on the coordinated regulation of midgut microbiota and miRNA in the infection of dengue virus to Ae. albopictus. Therefore, in this study we will investigate the affects of midgut microbiota to the fitness of Ae. albopictus (number of eggs, survival time and the hatching rate) and discuss the reciprocal regulation among midgut microbiota and miRNA. Firstly, composition of midgut microbiota and expression level of miRNA of Ae. albopictus will be detected based on the high-throughput sequencing technology following the infection of dengue virus. And then, the influence of midgut microbiota and miRNA on the infection level of dengue virus to Ae. albopictus will be explored using microecology methods and overexpression or suppression of specific miRNA. Finally, the coordinated of midgut microbiota and miRNA in regulate of infection efficiency of dengue virus to Ae. albopictus will be illuminated. Research of this study would provide theoretical basis for the development of efficient methods to prevent and control of Ae. albopictus and dengue fever.

白纹伊蚊是登革热的重要传播媒介之一，随着白纹伊蚊在全球的快速扩散，登革热已成为全球最严重的蚊媒病毒病之一。肠道细菌和微小RNA（miRNA）在蚊虫生长发育、营养代谢、免疫防御等多个方面均具有重要作用。中肠是登革热病毒感染、复制和传播的第一道屏障，但有关肠道细菌和中肠miRNA对白纹伊蚊感染登革热病毒的协同调控作用仍未有研究。本项目将深入研究肠道细菌对白纹伊蚊适合度（产卵量、存活时间和孵化率）的影响，探讨肠道细菌和中肠miRNA的相互调控作用。基于高通量测序技术研究登革热病毒感染对肠道细菌组成及中肠miRNA表达水平的影响；通过微生态学技术和过表达或抑制目标miRNA的方法，探究肠道细菌和中肠miRNA对白纹伊蚊感染登革热病毒情况的影响，进而探讨肠道细菌和中肠miRNA在白纹伊蚊感染登革热病毒效率方面的协同调控作用。本项目的开展将为开发白纹伊蚊和登革热的高效综合防制方法奠定理论基础。

白纹伊蚊是登革热病毒的重要传播媒介，也是全球100种最具入侵性的物种之一。由于缺乏安全有效的疫苗和抗病毒药物用于登革热的特异性预防，蚊媒防制仍是防控该病的主要手段。本项目通过分离培养共获得17株可培养的白纹伊蚊共生细菌，发现不同发育阶段的菌群多样性存在明显差异；感染登革热病毒导致白纹伊蚊共生菌群的组成和多样性均发生明显变化，其中12个物种的丰度显著下调，9个物种的丰度显著上调。白纹伊蚊感染登革热病毒后，中肠的15个miRNA的表达量上调，6个miRNA的表达量下调；257个lncRNA的表达量上调，102个lncRNA的表达量下调；发现并验证miR-989的表达量与登革热病毒的感染密切相关，且可以显著影响DENV2在C6/36细胞中的复制水平。基于基因间的调控关系构建了以miR-989为中心的调控网络，发现23个lncRNA、2个mRNA与miR-989间存在直接调控关系。相关研究结果将为利用共生细菌防控白纹伊蚊、解析共生细菌和miRNA调控登革热病毒感染效率等方面的研究提供基础资料。