Somasekhar M B, Gorski J
Department of Biochemistry, College of Agriculture and Life Sciences, University of Wisconsin-Madison 53706.
Gene. 1988 Sep 15;69(1):23-8. doi: 10.1016/0378-1119(88)90374-5.
We have used MCF-7, the human breast cancer cell line, which is estrogen receptor-positive, and the HeLa cell line, which is estrogen receptor-negative, to study the mechanisms by which estrogen induces prolactin gene transcription. A series of plasmids were constructed which direct the expression of the easily assayed bacterial enzyme chloramphenicol acetyltransferase. We have used these recombinants to show that the estrogen-responsive DNA element (ERE) required for the estrogenic regulation of the rat prolactin gene is functional in MCF-7 cells but not in HeLa cells. Specifically, in MCF-7 cells this element enhances the level of gene activity after estrogen treatment both from its own promoter and from a heterologous (simian virus 40) promoter. Results of these studies also show that in HeLa cells the ERE can mediate estrogenic regulation if cotransfected with a plasmid that can synthesize estrogen receptor.
我们使用了雌激素受体阳性的人乳腺癌细胞系MCF - 7和雌激素受体阴性的HeLa细胞系，来研究雌激素诱导催乳素基因转录的机制。构建了一系列指导易于检测的细菌酶氯霉素乙酰转移酶表达的质粒。我们利用这些重组体表明，大鼠催乳素基因雌激素调节所需的雌激素反应性DNA元件（ERE）在MCF - 7细胞中具有功能，但在HeLa细胞中则没有。具体而言，在MCF - 7细胞中，该元件在雌激素处理后，既能增强其自身启动子的基因活性水平，也能增强异源（猿猴病毒40）启动子的基因活性水平。这些研究结果还表明，在HeLa细胞中，如果与能合成雌激素受体的质粒共转染，ERE可以介导雌激素调节。
