重要媒介蚊虫昼夜节律的分子调控机制

白纹伊蚊和致倦库蚊是重要的媒介蚊虫，拥有明显且不同的昼夜节律。昼夜节律对于媒介蚊虫的吸血传病及其防制非常重要。虽然2017年诺贝尔奖颁予了“生物昼夜节律的分子机制”领域的研究成果，但目前对蚊虫昼夜节律的调控机制却知之甚少。本项目拟在前期对白纹伊蚊嗅觉发生、性别决定等工作基础上，针对重要蚊媒的昼夜节律展开研究：（1）运用基因组和生物信息学技术，克隆鉴定白纹伊蚊和致倦库蚊的昼夜节律基因；（2）进行转录组测序，分析不同时间点昼夜节律基因的表达谱特征；（3）进行ChIP-seq，分析与CLK/CYC异二聚体结合的昼夜节律基因及其表达调控；（4）进行小RNA测序，分析miRNA的表达规律及其对昼夜节律基因的调控作用；（5）对候选的昼夜节律基因和调控分子进行knock in/knock out的功能分析。研究目标是阐明白纹伊蚊和致倦库蚊昼夜节律的调节机制，为重要媒介蚊虫的防制提供分子靶标和科学指引。

Aedes albopictus and Culex quinquefasciatus are the most common but critical vectors that transmit many viral diseases all over the world. Interestingly, two species of mosquitoes possess sophisticated circadian clocks but completely different nyctohemeral rhythms, i.e., Ae. albopictus is diurnal, while Cx. quinquefasciatus keeps nocturnal. The 2017 Nobel Prize has been awarded for the work on discoveries of molecular mechanisms controlling the circadian rhythm, yet the role of circadian clocks in the mosquitoes remains unknown. Consequently, based on our previous studies on olfactory and sex determination in Ae. albopictus, we propose to carry out the specific aims as follows: (1) Characterize the circadian genes in both Ae. albopictus and Cx. quinquefasciatus using bioinformatics and molecular cloning; (2) Analyze the expression profile of the circadian genes at different time points using RNA-sequencing technology; (3) Perform ChIP-seq to analyze regulation and expression of the CLK/CYC heterodimer; (4) Conduct microRNA-sequencing to identify miRNAs that regulate the expression of the circadian genes; (5) Knock in and/or knock out candidate circadian genes to verify their functions. The overall objectives of the proposal are determining and demonstrating mechanisms of expression and regulation of the circadian genes in Ae. albopictus and Cx. quinquefasciatus, which would potentially explain the reason that cause distinct nyctohemeral rhythms and lead to control vector-borne infectious diseases.