lncRNA-miRNA网络调控Fn14基因表达及其在皮肌炎骨骼肌损伤中的作用机制研究

Skeletal muscle damage is the leading cause of muscle weakness suffered by dermatomyositis (DM) patients. However, the molecular mechanism remains unclear. In previous study, we found significantly up-regulated expression of TWEAK/Fn14 in DM muscle tissue. Additionally, lncRNA-p0127 was found to be highly expressed in DM muscle by microarray and qPCR analyses, and significantly correlated with the expression of Fn14 mRNA. Further bioinformatics prediction analysis revealed that lncRNA-p0127 may probably be a regulatory RNA targeting to Fn14. In the present proposal, we will address the following issues by using biological techniques such as FISH, RNAi, and RNA immunoprecipitation: (1) The pathogenic role of dysregulated TWEAK/Fn14 axis in muscle damage of DM patients. (2) The molecular mechanism of lncRNA-p0127 regulating Fn14 expression by functioning as a competing endogenous RNA of miRNAs. Our study will probably clarify the role of lncRNA-p0127-miRNA interaction in Fn14 gene regulation and DM muscle damage, and therefore could provide novel insights for the discovery of new targeted therapy for DM.

骨骼肌损伤是导致皮肌炎(DM)患者肌无力的重要原因，但其分子机制仍不明确。我们前期研究证实：(1) TWEAK/Fn14在DM骨骼肌组织中表达异常升高；(2) lncRNA-p0127在DM骨骼肌组织显著高表达，且与Fn14 mRNA表达水平高度相关；生物信息学预测分析提示Fn14是lncRNA-p0127调控的靶基因。本项目通过采用FISH、RNAi、RIP等技术，在DM骨骼肌细胞及成肌细胞中探讨：(1)TWEAK/Fn14通路异常活化在DM骨骼肌细胞损伤中的作用；(2)lncRNA-p0127通过竞争性结合miRNA调控肌细胞Fn14表达的分子机制。本研究有望系统阐明lncRNA-p0127-miRNA相互作用调控Fn14基因表达、参与DM骨骼肌损伤的分子机制，为皮肌炎的治疗靶点发现提供新思路。

骨骼肌损伤是导致皮肌炎(DM)患者肌无力的重要原因，但其分子机制仍不明确。有文献报道骨骼肌细胞自噬的过度活化是DM患者肌肉损伤的机制之一，但是其中的分子通路、信号途径仍不清楚。在国家自然科学基金委的资助下，我们按照研究计划,系统的探讨了TWEAK/Fn14在DM骨骼肌组织中的表达异常及其促进肌细胞自噬活化在皮肌炎骨骼肌损伤中的作用机制，并充分研究了lncRNA-p0127，miRNA-19a-3p，Fn14三者之间相互作用在肌细胞自噬损伤中的机制。主要取得如下成果： (1)证实TWEAK/Fn14在DM骨骼肌组织中表达异常升高；细胞水平证实TWEAK刺激成肌细胞可能通过活化细胞自噬而导致肌细胞损伤，并且这种影响是Fn14蛋白依赖的。（2）miRNA和mRNA芯片研究提示lncRNA-p0127、hsa-miR-19a-3p与Fn14 mRNA存在序列上的相似性，双荧光素酶报告基因试验证实hsa-miR-19a-3p可以直接调控Fn14基因的表达，基因敲降、过表达研究结果表明lncRNA-p0127是通过调控hsa-miR-19a-3p而影响Fn14的表达；这些结果表明lncRNA-p0127可能作为一种miRNA分子海绵，促进Fn14蛋白的表达。项目执行期间，共发表标注基金资助号SCI论文10篇，1人次在国际会议中做大会发言，团队中1名研究人员获得北京市科委课题的资助，1人获得职称晋升,培养博士研究生1人。