HE4荧光素酶报告基因载体构建与鉴定及其在肾脏纤维化中的作用

Construction and Identification of Luciferase Reporter Vector for HE4 Promoter and the Role of HE4 in the Renal Fibrosis

目的:通过构建HE4荧光素酶报告基因载体以及质粒转染以分析HIF-1α对HE4靶向调控,明确HE4调控肾脏纤维化的分子机制。方法:采用巢式PCR扩增HE4启动子片段,纯化酶切后定向克隆进p GL-3basic报告基因载体,进而与PRL-TK质粒共转染HK2细胞,检测荧光素酶的表达HIF-1α过表达质粒转染HK2细胞,western blot检测HE4分子的表达。HK2细胞转染HE4过表达质粒后检测COL4A1、COL1A1分子的表达。结果:获得HE4启动子荧光素酶报告载体,酶切鉴定结果与初期预测一致,荧光素酶检测结果证实HIF-1α可结合于HE4启动子上,从而启动HE4的表达。HK2细胞转染HIF-1α正义过表达质粒,HE4的m RNA和蛋白水平均显著增加。HK2细胞转染HE4过表达质粒,COL4A1、COL1A1表达水平上调。结论:本研究成功构建HE4启动子荧光素酶报告基因载体,证实HIF-1α为HE4上游靶基因,过表达的HE4可能通过上调COL4A1、COL1A1促进细胞外基质沉积促进肾脏纤维化的发生发展。

Objective： To determine the targeted regulating role of HIF-1α on the expression of HE4 based on a constructed luciferase reporter HE4 gene vector and the transfeetion of pcDNA-HIF-1α, and investigate the mechanisms of HE4 mediated renal fibrosis. Methods： The sequence of was chemically synthesized and directionally cloned into pGL3-BASIC. The recombinant pGL3-HE4 luciferase reporter vector was identified by PCR, enzyme digestion. Then both pGL3-HE4 and pcDNA3.1-HIF-1α transfected into HK2 cells to detect the activity of luciferase. Western blot qRT-PCR was used to analyzed the relationship between hif-let and HE4 after HK2 cells transfected with pcDNA3.1-HIF-1α. The mechanisms of HE4 mediated renal fibrosis was analyzed by western blot, qRT-PCR after HK2 cells was transfected with pcDNA3.1-HE4 or added the recombinant protein of HE4. Results： The pGL3-HE4 luciferase reorter vector had been identified by enzyme digestion as expectably. The hif-1α could bind to the region of HE4 promoter to promote the tran- scription of HE4. The expression of HE4 was significantly increased after transfected with peDNA3.1-HIF-1α in HK2 cells （P 〈0.05）. After transfected with pcDNA3.1-HE4 in HK2 cells, the expression of COL4A 1, COL1A1 was also significantly increased （P 〈 0.05）. Conclusion： The luciferase reporter vector of HE4 was successfully constructed and provided a tool for further studying. HE4 was targeted by HIF-1α and overexpression of HE4 could promote the accumulation of ECM involved in the regulation of renal fibrosis by upregulating the expression of COL4A1 and COL1A1.