Grippo J F, Holmgren A, Pratt W B
J Biol Chem. 1985 Jan 10;260(1):93-7.
Extraction of rat liver cytosol with charcoal inactivates glucocorticoid-binding capacity and receptors can be reactivated to the steroid-binding state by an endogenous reducing system utilizing NADPH and a Mr = 12,000, heat-stable, endogenous, cytosolic protein (Grippo, J. F., Tienrungroj, W., Dahmer, M. K., Housley, P. R., and Pratt, W. B. (1983) J. Biol. Chem. 258, 13658-13664). In this paper we show that NADPH-dependent conversion of the rat liver glucocorticoid receptor from a nonbinding to a steroid-binding form is blocked in an immune-specific manner by antisera raised against purified rat liver thioredoxin reductase or thioredoxin. The inhibition produced by thioredoxin reductase antiserum may be circumvented by dithiothreitol or overcome by addition of purified thioredoxin reductase. These observations prove that the endogenous glucocorticoid receptor-activating factor is thioredoxin and that the enzyme required for generating the steroid-binding conformation of the glucocorticoid receptor by the endogenous receptor-activating system is thioredoxin reductase.
用活性炭提取大鼠肝脏胞质溶胶会使糖皮质激素结合能力失活，而利用NADPH和一种分子量为12,000、热稳定的内源性胞质蛋白的内源性还原系统可将受体重新激活至类固醇结合状态（Grippo, J. F., Tienrungroj, W., Dahmer, M. K., Housley, P. R., and Pratt, W. B. (1983) J. Biol. Chem. 258, 13658 - 13664）。在本文中，我们表明，针对纯化的大鼠肝脏硫氧还蛋白还原酶或硫氧还蛋白产生的抗血清以免疫特异性方式阻断了大鼠肝脏糖皮质激素受体从非结合形式向类固醇结合形式的NADPH依赖性转化。硫氧还蛋白还原酶抗血清产生的抑制作用可被二硫苏糖醇规避，或通过添加纯化的硫氧还蛋白还原酶克服。这些观察结果证明，内源性糖皮质激素受体激活因子是硫氧还蛋白，并且内源性受体激活系统产生糖皮质激素受体类固醇结合构象所需的酶是硫氧还蛋白还原酶。
