桥粒斑蛋白DSP参与II型肺泡上皮细胞线粒体凋亡途径在特发性肺纤维化机制中的研究

Desmoplakin (DSP) is a GWAS-identified genetic risk locus in idiopathic pulmonary fibrosis (IPF). IPF subjects express a significantly higher level of DSP than control subjects. Our recent study revealed the potential mechanisms by which IPF regulates DSP overexpression. We demonstrated that stiff matrix promotes DSP overexpression through induction of demethylation of the DSP promoter in vitro and developed CRISPR/dCas9/Dnmt3A-mediated epigenome editing to reverse stiff matrix-induced DSP overexpression by epigenetic reprogramming of methylation of the DSP promoter. However, the function of DSP in the pathogenesis of IPF remains unclear. DSP as a major desmosomal protein plays a critical role in the maintenance of epithelial barrier function and the regulation of wound healing. We speculate that DSP promotes IPF by regulate actin cytoskeleton remodeling, inhibit Mkl1 nuclear translocation, reduce the expression of Bcl-2 and induce apoptosis of alveolar epithelial type II cells. Reverse DSP overexpression and protect against lung fibrosis in vivo by CRISPR/dCas9–mediated epigenome editing. This study will investigate the role of DSP in IPF and determine whether the DSP alters disease progression in IPF.

全基因组关联研究发现桥粒斑蛋白DSP在特发性肺纤维化IPF患者肺中的表达显著增加，是IPF疾病的风险基因。我们近期的研究发现硬基质通过诱导DSP启动子去甲基化从而促进DSP过表达，揭示了IPF调节DSP过表达的机制。通过运用表观基因组编辑工具CRISPR/dCas9/Dnmt3a，证明了靶向DSP启动子甲基化能够逆转硬基质诱导的DSP过表达。然而，DSP如何促进IPF的作用机制还不清楚。DSP作为主要的桥粒蛋白在维持上皮细胞功能和调节伤口愈合中起关键作用。推测DSP通过介导肌动蛋白细胞骨架重排，抑制Mkl1入核，降低Bcl-2表达，启动线粒体凋亡途径，诱导Ⅱ型肺泡上皮细胞凋亡，促进肺纤维化。本项目中拟运用CRISPR/dCas9/Dnmt3a表观基因组编辑技术调节DSP的表达，探讨DSP在IPF中的作用机制，为进一步阐明IPF发病机制和寻找新的基因治疗途径提供理论依据。

全基因组关联研究发现桥粒斑蛋白DSP在特发性肺纤维化IPF患者肺中的表达显著增加，是IPF疾病的风险基因。我们前期研究发现硬基质通过诱导DSP启动子去甲基化从而促进DSP过表达，揭示了IPF调节DSP过表达的机制。通过运用表观基因组编辑工具CRISPR/dCas9/Dnmt3a，证明了靶向DSP启动子甲基化能够逆转硬基质诱导的DSP过表达。然而，DSP如何促进IPF的作用机制还不清楚。DSP作为主要的桥粒蛋白在维持上皮细胞功能和调节伤口愈合中起关键作用。我们的研究发现DSP通过介导肌动蛋白细胞骨架重排，抑制Mkl1入核，降低Bcl-2表达，启动线粒体凋亡途径，诱导上皮细胞凋亡，促进肺纤维化。本项目中拟运用CRISPR/dCas9/Dnmt3a表观基因组编辑技术调节DSP的表达，探讨DSP在IPF中的作用机制，为进一步阐明IPF发病机制和寻找新的基因治疗途径提供理论依据。