生长激素释放剂受体启动子的结构和功能分析

Construction and function analysis of growth hormone secretagogue receptor promoter

目的 利用构建好的含有生长激素释放剂受体（GHS-R）启动子区不同长度的缺失突变体的重组质粒,对GHS-R启动子区的结构和功能进行初步分析.方法 将重组质粒转染GH3细胞,用双荧光素酶报道系统检测各个重组子的启动子活性,筛选GHS-R启动子区重要的转录调控区域.结果 pGL3-Enhancer-B相对活性（8.40±0.86）比pGL3-Enhaneer-A（2.30±0.21）显著升高;pGL3-Enhancer-C相对活性（5.20±0.30）比pGL3-Enhancer-B（8.40±0.86）明显下降;pGL3-Enhancer-D相对活性（10.60±0.54）比pGL3-Enhancer-C（5.20±0.30）明显升高;pGL3-Enhancer-E相对活性（14.10±0.74）比pGL3-Enhancer-D（10.60±0.54）明显升高.结论 GHS-R启动子上游-254～-168之间,-625～-355之间,-910～-625之间存在正性调控区域;而在-355～-254之间存在负性调控区域.

Objective To analyze the structure and function of growth hormone secretagogue receptor （GHS-R） promoter region primarily by using the constructed recombinant reporter gene promoter pGB-enhancer vectors containing different lengths of GHS-R promoter deletion mutants. Methods The recombinant plasmids were transfected into CH3 cells, then the promoter activities of different recombinant plasmids were detected by the Dual Luciferase Reporter Assay System. Results It was found that the promot er activities of pGL3-Enhancer-A,-B,-C,-D, and-E were （2. 30 ± 0. 21）, （8.40 ±0.86） , （5.20 ± 0.30）, （10.60 ±0.54） and （14.10 ±0.74） respectively,and there was significant difference between pGL3-Enhancer A,and-B,pGL3-Enhancer-B and-C, between pGL3-Enhancer-C, and-D,and between pGL3-Enhancer-D and-E （all P〈0.05）. Conclusion There was a positive transcriptional regulation region from-254 to-168,-625 to-355,-910 to-625 respectively,and a negative transcriptional regulation region be tween-355 to-254 in the upstream of the human GHS-R promoter.