Adan R A, Walther N, Cox J J, Ivell R, Burbach J P
Department of Pharmacology, Rudolf Magnus Institute, University of Utrecht, The Netherlands.
Biochem Biophys Res Commun. 1991 Feb 28;175(1):117-22. doi: 10.1016/s0006-291x(05)81208-2.
DNA sequences in the 5'-flanking region of rat and bovine oxytocin genes were examined for their capacity to confer estrogen responsiveness to their homologous promoters. In contrast to the 5'-flanking region of the rat oxytocin gene, upstream promoter sequences up to 3200 bp of the bovine gene linked to the chloramphenicol acetyltransferase (CAT) reporter gene which were transfected in estrogen receptor expressing MCF-7 cells did not respond to estrogen. Testing 5'-deletion mutants of the rat upstream region linked to the luciferase gene in P19 embryocarcinoma cells co-transfected with an estrogen receptor expression plasmid showed that two regions each associated with approximately 15-fold stimulation of promoter activity were located between nucleotides -172 and -149 and between -148 and +16 in the rat gene. The former region contains the imperfect palindrome GGTGACCTTGACC which differs in one nucleotide from the estrogen response element (ERE) consensus. It is concluded that the corresponding motive CATAACCTTGACC of the bovine gene is not a functional ERE. Thus, the estrogen responsiveness of oxytocin genes is species-dependent.
对大鼠和牛催产素基因5'-侧翼区域的DNA序列进行了检测，以考察它们赋予同源启动子雌激素反应性的能力。与大鼠催产素基因的5'-侧翼区域不同，与氯霉素乙酰转移酶（CAT）报告基因相连的牛基因上游长达3200 bp的启动子序列，在转染了雌激素受体的MCF-7细胞中对雌激素没有反应。在用雌激素受体表达质粒共转染的P19胚胎癌细胞中，对与荧光素酶基因相连的大鼠上游区域的5'-缺失突变体进行检测，结果表明，在大鼠基因中，有两个区域分别与启动子活性约15倍的刺激相关，位于核苷酸-172和-149之间以及-148和+16之间。前一个区域含有不完全回文序列GGTGACCTTGACC，与雌激素反应元件（ERE）共有序列有一个核苷酸的差异。得出的结论是，牛基因相应的基序CATAACCTTGACC不是一个功能性ERE。因此，催产素基因的雌激素反应性具有物种依赖性。
