Identification and localization of steroid-binding and nonsteroid-binding forms of the glucocorticoid receptor in the mouse P1798 lymphosarcoma.

摘要: Glucocorticoid receptors (GCRs) were characterized in sublines of the mouse P1798 lymphosarcoma that are sensitive (S) or resistant (R) to glucocorticoid-mediated apoptosis. Previous work had identified two steroid-binding GCRs S and R cells: a 97 kDa wild-type GCR cells (WT-GCR), 45 truncated (TR-GCR). A third GCR, nonsteroid-binding (NSB-GCR), was also cells. Using subcellular fractionation Western blotting, we now show contrast WT-GCR which is localized both cytoplasm nucleus cells, NSB-GCR predominantly cell nuclei. Moreover, gel filtration chromatography revealed treatment with 400 mM NaCl heat did not significantly alter Stokes radius suggesting this receptor present heterooligomeric complex other proteins. The TR-GCR soluble cytoplasmic fraction but crude membrane fractions nuclei, tightly associated nuclear structures. It detected fraction. Unexpectedly, immunoreactive protein These studies describe system necessitates further consideration glucocorticoid signaling