C/EBP-α蛋白赖氨酸乙酰化调控及其促进激活的HSCs凋亡的作用和分子机制研究

项目名称： C/EBP-α蛋白赖氨酸乙酰化调控及其促进激活的HSCs凋亡的作用和分子机制研究

项目编号： No.81470857

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 医药、卫生

项目作者： 刘秀萍

作者单位： 复旦大学

项目金额： 73万元

中文摘要： 肝星状细胞（HSCs）分化类似于脂肪细胞，调控脂肪细胞分化的 C/EBPs参与HSCs的调控。我们原创性体内、外研究已证实，C/EBP-α基因能诱导激活的HSCs凋亡使肝纤维化减轻但对肝细胞影响甚微；更为重要的是我们近期实验首次发现，C/EBP-α蛋白存在赖氨酸乙酰化修饰及乙酰化调控能促进其蛋白的表达和激活的HSCs凋亡，故科学地推测：C/EBP-α蛋白介导其乙酰化调控促进HSCs凋亡在肝纤维化过程中发挥着重要的作用，其可能是抑制/逆转肝纤维化的突破口。我们预实验的初步结果和科学推测等一系列问题尚需要严谨地证实和深入研究，因此，我们拟在本课题通过质谱分析、免疫共沉淀、基因定点突变等方法证实C/EBP-α蛋白的乙酰化修饰和相关问题，及其对HSCs凋亡的促进作用和分子机制；通过肝纤维化动物模型观察HDACs抑制/逆转肝纤维化和肝功能恢复的效果，为肝纤维化病人的防治提供新的思路和理论实验基础。

中文关键词： 肝纤维化；CCAAT增强子结合蛋白-；alpha；肝星状细胞；乙酰化；细胞凋亡

英文摘要： The differentiation of hepatic stellate cells (HSCs) is similar to that of adipocytes, therefore, the CCATT/enhancer binding proteins (C/EBPs) which play an important role in the differentiation of adipocytes, also regulate alterations of HSCs. We originally confirmed by in vivo and in vitro researches that C/EBP-α gene could relieve liver fibrosis through the induction of activated-HSCs apoptosis, and this effect of C/EBP-α gene have little impact on hepatocytes. More importantly, our recent preliminary experiments showed for the first time that lysine-acetylation exists in C/EBP-α protein and this modification could promote the expression of C/EBP-α protein and activated-HSCs apoptosis. These findings suggest that the acetylation of C/EBP-α protein may regulate the apoptosis of activated-HSCs, and possibly play an important role in liver fibrosis. The acetylation of C/EBP-α protein may be a breakthrough point of reversion of liver fibrosis. But these hypotheses still need further confirmation. Therefore, in this project, we will identify the specific acetylation and site in C/EBP-α protein, and explore the mechanisms of HSCs apoptosis induced by acetylated C/EBP-α protein. The main methods include mass spectrometry, co-immunoprecipitation and site-directed gene mutagenesis. Furthermore, we will observe the effect of histone deacetylase inhibitors (HDACIs) to reverse/relieve liver fibrosis and recovery of liver function through the liver fibrosis through animal model. This research will provide the new ideas and strategy for prevention and treatment of liver fibrosis.

英文关键词： liver fibrosis;C/EBP-α（CCAAT enhancer binding protein- alpha）;HSCs（hepatic stellate cells）;acetylation;apoptosis