颗粒细胞PPARG基因剪接变体在PCOS发病机制中的作用

Polycystic ovary syndrome (PCOS) is characterized by ovulation dysfunction, hyperandrogenism and polycystic ovary morphology, which jeopardizes women’s reproductive health. Moreover, approximately 50–70% of patients have insulin resistance, and increased risks of diabetes and cardiovascular diseases. The etiology of PCOS is still unknown. Peroxisome proliferator-activated receptor-gamma（PPARG）is an important regulator of follicular development, ovarian steroid hormone synthesis/metabolism, cell cycle regulation and glycometabolism. Recently, we firstly find PPARG pre-mRNA splicing variants in ovarian granulosa cells of PCOS patients, suggesting a role of PPARG in the pathogenesis of PCOS. In this study, we plan to detect the expression level, translation efficiency and protein structure of different PPARG splicing variants by quantitative PCR, bioinformatics and luciferase reporter technology. Then we aim to analyze the parental origin and cis-elements using heterozygous SNP site analysis and DNA sequencing of flanking fragments. Furthermore, we intend to utilize in vitro cell model and transcription factor assay to investigate the impact of androgen on the expression of PPARG splicing variants and the transcriptional regulation mechanism. Lastly, we aim to reveal the effect of PPARG splicing variants on expression of down-stream target genes by RNA-seq and ChIP-seq, and check the function of granulose cells with cell models. Thus, the present study would clarify the epigenetic role of PPARG splicing variants in the pathogenesis and throw new light on the treatment of PCOS.

多囊卵巢综合征（PCOS）以排卵障碍、高雄激素和卵巢多囊改变为特征，还常合并胰岛素抵抗，发生糖尿病和心血管疾病的风险上升，严重威胁女性健康，但其病因不明。我们首次发现PCOS患者颗粒细胞中存在过氧化物酶体增生物激活受体γ（PPARG）的剪接变体，且与高雄激素有关。PPARG是卵巢甾体激素合成代谢和卵子发生的重要调节因子，本项目拟通过测序、荧光素酶报告实验明确临床患者颗粒细胞中各型PPAR剪接变体的表达丰度、蛋白空间结构及翻译效率；结合体外细胞实验、染色质免疫共沉淀、DNA定点突变分析高雄对剪接变体表达的影响；利用转录组、ChIP-seq探索剪接变体对下游基因调控及颗粒细胞激素合成、增殖、凋亡、缝隙连接等功能的影响，从而阐明PPARG剪接变体在PCOS发生中的作用及其机制。本研究有助于解析PCOS的发病机理，为其治疗和遗传阻断提供理论基础，具有重大的科研价值和社会意义。