Tsai S Y, Tsai M J, O'Malley B W
Department of Cell Biology, Baylor College of Medicine, Houston, Texas 77030.
Cell. 1989 May 5;57(3):443-8. doi: 10.1016/0092-8674(89)90919-7.
We demonstrated previously that two molecules of steroid hormone receptor bound efficiently to a single hormone response element (GRE/PRE) of the tyrosine aminotransferase gene (Tsai et al., 1988). Here, we show that two tandemly linked GRE/PREs conferred progesterone inducibility synergistically to a heterologous TK-CAT fusion gene. Binding studies demonstrated that occupation of one GRE/PRE site by a progesterone receptor dimer increased the binding affinity of receptors for the second GRE/PRE site 100-fold. Thus, the observed synergistic induction of TK-CAT may result from cooperative binding of receptor dimers to the two GRE/PRE sites.
我们之前证明，两分子类固醇激素受体可有效结合至酪氨酸转氨酶基因的单个激素反应元件（GRE/PRE）（Tsai等人，1988年）。在此，我们表明两个串联的GRE/PRE可协同赋予异源TK-CAT融合基因孕酮诱导性。结合研究表明，孕酮受体二聚体占据一个GRE/PRE位点会使受体对第二个GRE/PRE位点的结合亲和力增加100倍。因此，观察到的TK-CAT协同诱导可能是由于受体二聚体与两个GRE/PRE位点的协同结合所致。
