目前帕金森病(PD)的诊断还缺乏有效的生物标记物。本课题组前期通过病例对照研究发现miR-31在PD患者血清和脑组织中的表达均下降。生物信息学分析发现PD致病基因GIGYF2可能是miR-31的靶基因。我们推测：miR-31可能通过调节GIGYF2的表达而在PD发病中起重要作用。本研究拟首先通过荧光素酶基因报告实验验证GIGYF2是miR-31的靶基因，并确定miR-31可通过作用于GIGYF2促进MPP+诱导的细胞凋亡；然后通过建立PD细胞和小鼠模型确定miR-31可通过降低GIGYF2蛋白表达，进而激活PI3K／Akt信号通路和凋亡通路而参与PD发病的机制；再通过PD患者的脑组织标本，对此机制进行进一步验证。最后以血清miR-31作为生物标记物对PD病人进行为期4年的随访，确定其临床应用价值。本项目的研究结果有助于PD发病机制的阐明，为PD临床诊断提供新的生物标志物。

At present, there is no efficient biomarkers to diagnose Parkinson's disease (PD). Through case-control study our group previously found the level of miR-31 markedly decreased in the serum and brain tissues of PD. Bioinformatics analysis showed that GIGYF2 gene may be the target of miR-31. In this study, we will confirm GIGYF2 is the target of miR-31 by luciferase reporter assay. Then, we will demonstrate that overexpression of miR-31 could negatively regulate GIGYF2 expression and exacerbate MPP+-induced apoptosis. Through constructing MPP+-induced PD cell model and MPTP-induced PD mouse model, we will confirm that overexpression of GIGYF2 can reduce GIGYF2 expression, inhibit PI3K／Akt pathway and exacerbate apoptosis of cells. Furthermore, we will examine the effect of miR-31 on the expression of GIGYF2, the activities of PI3K／Akt pathway and apoptosis pathway using PD brain samples. Finaly, the clinical value of miR-31 will be verified by following up PD patients using miR-31 as a PD biomarker for 4 years. Results of this study will be helpful to elucidate the pathogenesis of PD, on the other hand, results of this study will provide a new biomarker for PD clinical diagnosis.