人NKX3.1基因启动子的克隆及在不同肿瘤细胞系中启动子活性的测定(英文)

Cloning of human NKX3.1 gene promoter and assay of its promoter activity in different tumor cell lines

目的:克隆NKX3.1基因启动子并检测其启动子活性,为研究NKX3.1基因转录调控的基本机制奠定基础。方法:采用PCR方法从人基因组中扩增NKX3.1基因上游1.04 kb启动子片段并分别克隆到报道基因载体pGL3-basic和pEGFP-1中,通过转染细胞、荧光素酶活性测定及荧光显微镜下观察绿色荧光蛋白的表达,检测其启动子活性。结果:DNA测序结果证实克隆的1.04 kb启动子片段序列正确;pGL3-1.04 kb启动子转染LNCaP细胞后,双荧光素酶活性测定M1/M2=2.7,为pGL3-control活性的1.5倍,为pGL3-basic活性的50倍。表明克隆的人NKX3.1基因上游1.04 kb片段具有较强的启动子活性。为检测此1.04 kb启动子在不同组织细胞中的活性,分别将pGL3-1.04 kb启动子和pEGFP-1.04 kb启动子转染入不同的肿瘤细胞系,检测荧光素酶和绿色荧光蛋白的表达。结果显示1.04 kb启动子在前列腺癌细胞LNCaP中活性最高。采用TRANSFAC数据库分析,发现在1 040 bp片段内含有多种顺式作用元件,它们的功能性将需要进一步实验证明。结论:克隆的人NKX3.1基因上游1.04 kb片段具有较强的启动子活性,并且在前列腺癌细胞LNCaP中活性最高。

AIM： To study the basic mechanism of transcriptional regulation, NKX3. 1 gene promoter was cloned and its promoter activities in prostate cancer cell lines and other cancer cell lines were tested. METHODS： 1.04 kb - promoter fragment of NKX3.1 gene was obtained by PCR and cloned into pGL3 - basic and pEGFP - 1 that are promoter - less reporter vectors to examine its promoter activity driving the reporter gene transcription. The promoter activity was determined by dual - luciferase reporter assay and the expression of GFP reporter observed under fluorescence microscope. RESULTS ： The sequence of the cloned 1.04 kb promoter proved to be correct by DNA sequencing. The dual - luciferase reporter assay （ M1/M2 ） showed that the promoter activity in LNCaP cell transfected with pGL3 - 1.04 kb promoter was about 1.5 - fold higher than that of pGL3 - control transfection and 50 - fold higher than that of pGL3 - basic transfection. To investigate the 1.04 kb - promoter activity in different tumor cell lines, the constructed pGL3 - 1.04 kb promoter and pEGFP - 1.04 kb promoter were transfected into several cell lines, respectively. The results showed that the activity of 1.04 kb promoter in LNCaP was highest among the tested cell lines. Multiple consensus sequence elements have been identified within the 1.04 kb fragment using TRANSFAC database. Further experiments will be done to determine their founctions. CONCLUSION： Cloned 1.04 kb fragment upstream of NKX3. 1 gene presented a strong promoter activity and its activity was highest in LNCaP cell among the tested tumor cell lines.