miR-204对人胚胎干细胞源性视网膜色素上皮细胞紧密连接的调控机制

Differentiating procedure from hESCs to RPE cells has been in improving and toward maturity in recent years. However, it has been put in the top studies for urgent attention how to get hESCs-derived RPE cells with features closer to hRPE. miRNAs play a critical role in epithelial cell phenotype and function. In our previous work, we studied the roles of miRNAs in directed differentiation of hESCs into RPE. A multitude of differentiatially expressed miRNAs were identified during differentiation. In the current project, we plan to further explore the mechanisms of miR-204 regulation, involved signaling pathways through targeting gene, and the morphology and molecular biological changes of tight junctions. The present study will undoubtedly deepen our understanding of molecular regulation mechanisms in hESCs-derived RPE cell physiology, aiming to achieve an improving procedure.

近年人胚胎干细胞（hESCs）向视网膜色素上皮（RPE）细胞的诱导分化体系日趋成熟，如何使hESCs源性RPE细胞生理特征更为接近RPE，受到关注。miRNA是细胞表型和功能的上游调节者，我们前期工作已完成hESCs向RPE细胞分化各阶段的miRNA差异表达及特征性基因变化的研究，本课题是之前研究的延续，选取miR-204作为研究靶点，通过验证可能的靶基因CTNNBIP1，分析经Wnt/beta-catenin信号传导通路所致细胞紧密连接形态学、跨膜电阻抗（TER）、分子水平的改变，对miR-204下游调控及功能机制进一步探讨，期望更深入的了解hESCs源性RPE细胞的生理调控机制，为分化体系的完善提供新方案。

人胚胎干细胞（hESCs）源性视网膜色素上皮（RPE）细胞具备治疗 RPE 损伤相关疾病的潜能。优化诱导分化体系，使 hESCs 源性 RPE 细胞表型和功能更接近 RPE 细胞，是目前亟待解决的问题。本项目建立了稳定的hESCs 向 RPE 细胞的诱导分化体系，证实hESCs 源性 RPE 细胞中 miR-204 靶向抑制 CTNNBIP1，调节细胞紧密连接的表达。通过miR-204过表达，细胞紧密连接claudin-10，16，19 和ZO-1表达增加，生长因子VEGF和PEDF的分泌极性增加，验证了miR-204对获得上皮特性和维持细胞极性的作用。项目还发现在hESCs源性RPE细胞的分化中，存在间质细胞向上皮转化的过程，miR-204可能在这一过程中起促进作用。本项目从miRNA角度提出开拓分化体系的调控关键节点，有助于获得更为成熟的优化方案。