Peroxidasin信号通路在先天性白内障发病中的分子机制研究

项目名称： Peroxidasin信号通路在先天性白内障发病中的分子机制研究

项目编号： No.81500708

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 医药、卫生

项目作者： 闫晓河

作者单位： 深圳大学

项目金额： 18万元

中文摘要： Peroxidasin(PXDN)基因突变导致人类先天性白内障、角膜混浊和发育性青光眼。申请人与合作者构建并鉴定首个PXDN基因突变小鼠疾病模型，其眼部表型与人类相似，点突变位于过氧化物酶功能域(T3816A)，并发现PXDN在晶状体上皮细胞表达，晶状体发育异常产生的先天性白内障是造成眼前段发育异常的首发因素。进一步实验显示，PXDN基因突变影响晶状体上皮细胞的增殖和分化以及晶状体囊膜的稳定，并影响眼发育重要基因Pax6和Foxe3的表达。那么，PXDN如何调控晶状体上皮细胞的增殖和分化？该过程涉及哪些信号分子及其转导通路？本研究拟进一步采用定点突变技术、子宫内胚胎电转、RNA干扰、Real-time PCR和Western blot等方法研究PXDN调控晶状体上皮细胞生物学活性的分子基础，阐明PXDN突变产生先天性白内障的分子机制，为PXDN作为先天性白内障治疗的靶点提供充分的科学依据。

中文关键词： 过氧蛋白；先天性白内障；晶状体上皮细胞；晶体发育；分子机制

英文摘要： Mutations in Peroxidasin (PXDN) cause severe anterior segment dysgenesis in humans, including congenital cataract, corneal opacity, and developmental glaucoma. Within an ENU (N-ethyl-N-nitrosourea) - mutagenesis screen, we identified the first mammalian model - ENU-induced PXDN mouse mutant line. We mapped the mutation to chromosome 12 within a critical interval of 2.4 Mb and sequence analysis of cDNA revealed a T3816A mutation resulting in a premature stop codon (Cys1272X) in the peroxidase domain. This mutation causes severe anterior segment dysgenesis and microphthalmia during eye development mimicing the manifestations in patients with PXDN mutations. Peroxidasin is highly expressed in the lens epithelial cells and inner retina. Aberrant lens development was firstly found in the mutants during eye development. Further, the proliferation and differentiation of the lens is disrupted in association with aberrant expression of transcription factor genes (Pax6 and Foxe3) in mutants at different embryonic periods. Additionally, PXDN is involved in the lens epithelium adhesion and consolidation of the basement membrane. However, The action of peroxidasin during lens development remains unclear. This study aims to investigate the molecular mechanisms of PXDN during lens development using site-direct mutagenesis、RNA sliencing, microarray, real-time PCR and western blot. The proposed work holds promise to provide insight into the pathogenesis of congenital cataract and establish peroxidasin as a potential therapeutic target.

英文关键词： Peroxidasin;Congenital cataract;Lens epithelial cells;Lens development;Molecular mechanism