Besson P, Fernandez-Rachubinski F, Yang W, Fliegel L
Department of Biochemistry, Faculty of Medicine, University of Alberta, Edmonton, Canada.
Am J Physiol. 1998 Mar;274(3):C831-9. doi: 10.1152/ajpcell.1998.274.3.C831.
We examined factors important in regulation of expression of the Na+/H+ exchanger gene in NIH/3T3 cells. A stable fibroblast cell line was generated that contained a 1.1-kb proximal fragment of the mouse NHE1 promoter. The addition of serum to serum-starved cells resulted in an increase in activity of the NHE1 promoter. The mitogenic agonists insulin, thrombin, and epidermal growth factor also increased transcription from the NHE1 promoter. Phorbol esters also increased NHE1 promoter-directed transcription, whereas the serine/threonine protein kinase inhibitor 1-(5-isoquinolinylsulfonyl)-2-methylpiperazine inhibited this stimulation. The protein kinase inhibitors GF-109203X, PD-98059, and genistein all stimulated promoter activity. Promoter deletion analysis and gel mobility shift assays showed that a region between 0.9 and 1.1 kb from the start site was involved in mediating the effect of mitogenic stimulation. The results show that a variety of mitogenic factors can activate the NHE1 promoter during cell growth and proliferation.
我们研究了在NIH/3T3细胞中对Na⁺/H⁺交换体基因表达调控至关重要的因素。构建了一个稳定的成纤维细胞系，其包含小鼠NHE1启动子的1.1 kb近端片段。向血清饥饿的细胞中添加血清会导致NHE1启动子活性增加。促有丝分裂激动剂胰岛素、凝血酶和表皮生长因子也会增加NHE1启动子的转录。佛波酯也会增加NHE1启动子指导的转录，而丝氨酸/苏氨酸蛋白激酶抑制剂1-(5-异喹啉磺酰基)-2-甲基哌嗪会抑制这种刺激。蛋白激酶抑制剂GF-109203X、PD-98059和染料木黄酮均刺激启动子活性。启动子缺失分析和凝胶迁移率变动分析表明，起始位点0.9至1.1 kb之间的区域参与介导促有丝分裂刺激的作用。结果表明，多种促有丝分裂因子在细胞生长和增殖过程中可激活NHE1启动子。
