Mason G G, Wilhelmsson A, Cuthill S, Gillner M, Poellinger L, Gustafsson J A
Department of Medical Nutrition, Karolinska Institutet, Huddinge University Hospital, Sweden.
J Steroid Biochem. 1988;30(1-6):307-10. doi: 10.1016/0022-4731(88)90112-4.
The binding of the rat hepatic dioxin and glucocorticoid receptors to the polyanionic matrices heparin-Sepharose and DNA-cellulose in vitro and to cell nuclei in vivo was studied under various conditions. In a non-liganded and non-activated state both receptors eluted from heparin-Sepharose at a low ionic strength and were not retained on DNA-cellulose. Following ligandation and activation in vitro both receptors showed an increased affinity for heparin-Sepharose and were retained on DNA-cellulose. In analogy to these in vitro data, it was found that a high salt concentration (0.4 M KCl) was required to extract in vivo liganded dioxin receptor from purified nuclear preparations in contrast to that previously reported for non-liganded nuclear receptors. Limited proteolysis of both dioxin and glucocorticoid receptors resulted in molecular species of similar binding properties with regard to DNA-cellulose and heparin-Sepharose. We conclude that, in addition to the dioxin and glucocorticoid receptors showing considerable similarities in their physicochemical properties, they may also share a similar structural organization with regard to functional domains.
在不同条件下，研究了大鼠肝脏二噁英受体和糖皮质激素受体在体外与多阴离子基质肝素 - 琼脂糖和DNA - 纤维素的结合，以及在体内与细胞核的结合。在非配体和未激活状态下，两种受体在低离子强度下从肝素 - 琼脂糖上洗脱下来，且不保留在DNA - 纤维素上。在体外进行配体结合和激活后，两种受体对肝素 - 琼脂糖的亲和力增加，并保留在DNA - 纤维素上。与这些体外数据类似，发现与先前报道的非配体核受体相比，从纯化的核制剂中提取体内配体化的二噁英受体需要高盐浓度（0.4 M KCl）。对二噁英受体和糖皮质激素受体进行有限的蛋白酶解，产生了在与DNA - 纤维素和肝素 - 琼脂糖结合特性方面相似的分子种类。我们得出结论，除了二噁英受体和糖皮质激素受体在物理化学性质上显示出相当大的相似性外，它们在功能域方面也可能具有相似的结构组织。
