Smith D L, Law R E, Shaw K J, Do Y S, Hsueh W A, Morris B J
Department of Internal Medicine, University of Southern California School of Medicine, Los Angeles 90033.
Biochim Biophys Acta. 1994 Oct 18;1219(2):465-74. doi: 10.1016/0167-4781(94)90073-6.
In order to determine the influence of proximal 5'-flanking DNA of the human renin gene (REN) in cells that express human renin, transient expression analyses were carried out in chorio-decidual cells. Constructs containing different lengths of REN promoter DNA, extending as far as 2595 bp upstream of the transcription start site, were unable to drive transcription of a chloramphenicol acetyl transferase reporter gene in chorio-decidual cells, nor in noncognate 293 or JEG-3 cells. The tk promoter was similarly inactive in constructs containing -2595 to -453 fragments of REN 5'-flanking DNA. In each cell type, the -2595 to -1300 DNA exerted a negative influence. Additional promoter- and cell type-dependent negative influences were noted for other regions of REN 5'-flanking DNA and the -453 to -145 DNA increased tk promoter activity 2.5-fold in chorio-decidual cells. By introducing the SV40 enhancer into constructs, a weak stimulation of the REN promoter was observed in chorio-decidual cells, but not in noncognate, JEG-3 cells, although the -2595 to -1300 DNA retained its negative influence in the cognate cell type. These results show that the proximal 2.6 kb of REN 5'-flanking DNA is unable to drive reporter gene activity in renin-synthesizing, chorio-decidual cells under basal conditions and suggest that trans-acting factors unique to at least this cell type, together with enhancer(s) located outside of the proximal 2.6 kb of REN promoter DNA tested, could be required for human renin promoter activity.
为了确定人肾素基因（REN）近端5'-侧翼DNA在表达人肾素的细胞中的影响，在绒毛膜蜕膜细胞中进行了瞬时表达分析。含有不同长度REN启动子DNA（延伸至转录起始位点上游2595 bp）的构建体，在绒毛膜蜕膜细胞、非同源的293细胞或JEG-3细胞中均无法驱动氯霉素乙酰转移酶报告基因的转录。tk启动子在含有REN 5'-侧翼DNA的-2595至-453片段的构建体中同样无活性。在每种细胞类型中，-2595至-1300 DNA均产生负面影响。对于REN 5'-侧翼DNA的其他区域，还发现了额外的启动子和细胞类型依赖性负面影响，并且-453至-145 DNA使绒毛膜蜕膜细胞中的tk启动子活性增加了2.5倍。通过将SV40增强子引入构建体，在绒毛膜蜕膜细胞中观察到REN启动子受到微弱刺激，但在非同源的JEG-3细胞中未观察到，尽管-2595至-1300 DNA在同源细胞类型中仍保留其负面影响。这些结果表明，在基础条件下，REN 5'-侧翼DNA近端的2.6 kb无法驱动肾素合成的绒毛膜蜕膜细胞中的报告基因活性，并表明至少这种细胞类型特有的反式作用因子，以及位于所测试的REN启动子DNA近端2.6 kb之外的增强子，可能是人肾素启动子活性所必需的。
