小鼠Na^+-K^+-2Cl^-共转运蛋白基因启动子克隆及20-HETE对其转录活性的影响

Cloning of the Murine Na^+-K^+-2Cl^-Cotransporter Gene Promoter and the Effect of 20-HETE on Its Transcriptional Activity

目的克隆小鼠Na^+-K^+-2Cl^-共转运蛋白(Nkcc2)基因启动子序列,初步探讨20-HETE对该基因转录活性的调控作用。方法应用生物信息学软件ALiBaba2.1和TRANSFAC TESS分析小鼠Nkcc2基因启动子序列;以小鼠基因组DNA为模板,利用PCR方法扩增得到小鼠Nkcc2基因启动子区片段(-1 462 bp～+40 bp),并克隆入pGL3-Basic载体,构建萤光素酶报告基因载体;脂质体法将重组报告基因载体转染到HEK293T细胞24 h后,再以20-HETE处理转染细胞2 h,利用双萤光素酶报告基因检测系统分析萤光素酶活性。结果成功构建小鼠Nkcc2基因启动子萤光素酶报告基因载体;20-HETE可以显著下调小鼠Nkcc2基因启动子萤光素酶报告基因载体的转录活性。结论 20-HETE通过转录调控机制下调小鼠Nkcc2基因的表达。

Objective To clone the murine Na^+-K^+-2Cl^- cotransporter( Nkcc2) gene promoter and analyze 20-HETE regulation of the murine Nkcc2 gene transcriptional activity. Methods A fragment of the murine Nkcc2 gene promoter was analyzed using bioinformatics software AliBaba and TRANSFAC TESS. The murine Nkcc2 gene promoter fragment(-1 462 bp -+40 bp) was amplified by PCR using murine genomic DNA as a template and then cloned into a pGL3-Basic vector to generate a luciferase reporter construct. The recombinant reporter construct was transiently transfected into HEK293T cells using Lipofectamine 2000 for 24 h. The transfected HEK293T cells were treated with 20-HETE for 2 h followed by measurement of the luciferase activity using the Dual-Luciferase Reporter Assay system. Results A luciferase reporter construct containing the murine Nkcc2 gene promoter was successfully generated. The results showed that 20-HETE significantly reduced the transcriptional activity of the construct. Conclusion 20-HETE may reduce the expression of the murine Nkcc2 gene through transcriptional regulation.