EGR3基因在精神分裂症网络调控中的分子机制研究

Our previous study has provided strong evidence that EGR3 is one of susceptibility genes of schizophrenia in Han Chinese population in northwest China. Accordingly, we propose to further investigate the role and molecular mechanism of EGR3 gene in SZ pathogenesis. First, we will use the techniques, such as Real-time PCR, Westernblotting, gene cloning and cell transfection in SZ case-control population, animal model and cell model to test the expression of EGR3 and its effect to the related neurons. Second, the downstream genes regulated by EGR3 will be screened and verified by RNAi, chip assay, and ChIP technology etc. in vitro; then the expression of the genes will be tested in vivo; furthermore, Taqman genotyping and association study will be performed in SZ case-control population to shed light upon the relationship between the genes and the disease. Finally, the SZ related neurotransmitter receptor antagonists were added to cells and the neurotransmitter system which mostly affected the expression of EGR3 and its signal transduction pathway will be determined by such as Real-time PCR methods; then the SZ related miRNA targeted EGR3 gene 3'UTR and the SZ related transcription factor targeted EGR3 gene reporter region will be validated by reporter gene assay and ChIP methods respectively. The results of this project will systematically demonstrate the role and molecular mechanism of EGR3 in schizophrenia and provide new methods and ideas for the development of clinical diagnosis and treatment.

我们前期在中国西北汉族人群中验证了早期生长反应基因3（EGR3）是精神分裂症（SZ）的易感基因。本研究首先在人群样本、在体模型和细胞模型中，用Real-time PCR、Western blotting、基因克隆及真核细胞转染等方法检测EGR3的表达及对相关神经元的作用。其次，采用RNAi、芯片、Real-time PCR、ChIP及Taqman基因分型等技术在细胞中筛选EGR3调节的下游基因，并在动物模型以及人群样本中进行验证。最后，用SZ相关神经递质受体拮抗剂处理细胞，Real-time PCR等方法筛选对EGR3表达影响最大的递质系统及其信号通路；报告基因系统及ChIP方法分别研究作用该基因 3'UTR区的SZ相关miRNAs及作用该基因启动子区的SZ相关转录因子。此项研究将揭示EGR3在SZ中的作用及网络调控中的分子机制，为疾病的临床诊断和防治提供新的方法和思路。

精神分裂症（SZ）是一种复杂性疾病，受遗传因素和环境因素的共同作用，其中遗传因素占80%左右。目前为止发现SZ易感基因有1000多种，生物大分子在调控过程中，存在着直接或间接的相互作用，形成复杂的网络调控。课题组在前期的研究中，在中国西北汉族人群中验证了EGR3基因是SZ的易感基因。EGR3作为一个转录因子，在SZ的网络调控中起到了重要的作用。在本项目的资助下，课题组对EGR3在SZ的中的功能及分子作用机制进行了深入细致的研究。研究发现，在首发SZ病人和MK-801诱导的细胞模型中，EGR3基因的表达发生了显著性的变化；生物信息学和分子生物学方法表明，几个和SZ相关的microRAN直接调控了EGR3基因的表达；芯片结果表明EGR3基因调控了和SZ相关的一些基因和相关的几个信号通路。目前实验正在进行细胞水平的ChIP实验验证和在体水平的实验验证及行为学测试。此项研究揭示了EGR3基因和谷氨酸神经递质通路相关，鉴定出了EGR3上游和下游作用的生物大分子，为疾病的临床诊断和防治提供了实验室数据和研究基础。