Ikeda K, Inoue S, Orimo A, Tsutsumi K, Muramatsu M
Department of Biochemistry, Saitama Medical School, Moroyama, Saitama 350-04, Japan.
Gene. 1998 Aug 17;216(1):155-62. doi: 10.1016/s0378-1119(98)00307-2.
The estrogen-responsive finger protein (efp) containing a RING finger motif has been identified as an estrogen-responsive gene in human and mouse. Here, we have characterized the basal promoter region of the mouse efp gene. The promoter lacks the TATA motif, and transcription initiation sites are found at positions -38T, -64A and -73C from the translation initiation site. Deletion analysis of the 5'-flanking region using Jyg-Mc(B) mouse breast cancer cells indicates that the sequence encompassing from -139 to -1 has a basal transcription activity. This region is GC-rich in both mouse and human promoters, and the E-box is precisely matched on the sequence alignment. A mutation experiment with E-box shows that the E-box is functionally active. An electrophoretic mobility shift assay using Jyg-Mc(B) nuclear extracts shows that a transcription factor, USF-1 binds to the E-box in the mouse efp promoter. It has been shown that the E-box in the human efp promoter is indispensable for basal transcriptional activity and binds USF-1. These findings suggest that the mouse efp promoter is regulated by a similar mechanism to that of the human. In mouse, however, we have not found a negative regulatory region that is present in human promoter.
含有泛素连接酶结构域的雌激素反应性指蛋白（Efp）已被鉴定为人类和小鼠中的一种雌激素反应基因。在此，我们对小鼠Efp基因的基础启动子区域进行了特征分析。该启动子缺乏TATA基序，转录起始位点位于翻译起始位点下游-38T、-64A和-73C处。利用Jyg-Mc(B)小鼠乳腺癌细胞对5'侧翼区域进行缺失分析表明，包含-139至-1的序列具有基础转录活性。该区域在小鼠和人类启动子中均富含GC，并且E盒在序列比对中精确匹配。对E盒进行的突变实验表明该E盒具有功能活性。使用Jyg-Mc(B)细胞核提取物进行的电泳迁移率变动分析表明，转录因子USF-1与小鼠Efp启动子中的E盒结合。研究表明，人类Efp启动子中的E盒对于基础转录活性不可或缺且能结合USF-1。这些发现表明，小鼠Efp启动子受与人类启动子类似的机制调控。然而，在小鼠中，我们未发现人类启动子中存在的负调控区域。
