Identification of a macromolecular inhibitor of glucocorticoid-receptor complex activation in rat liver cytosol.
We have identified an endogenous regulator of the glucocorticoid receptor following fractionation of dialyzed rat liver cytosol on DEAE-cellulose. The macromolecular regulator, purified approximately 20-fold as judged by Lowry-reactive material, inhibits activation of glucocorticoid-receptor complexes when assayed by DNA-cellulose binding and by chromatography on DEAE-cellulose minicolumns. In addition the active DEAE-cellulose fraction stabilizes the unoccupied glucocorticoid receptor against heat inactivation. Evidence is presented that the observed inhibition of activation by the active DEAE-cellulose fraction is not due to concentration of cytosolic proteases or RNA. The inhibitory molecule in the active fraction is not stable to heating at 90 degrees C (15 min) and is partially inactivated at 45 degrees C (15-60 min).
D000315:Adrenalectomy; D000818:Animals; D002848:Chromatography, DEAE-Cellulose; D003600:Cytosol / Q000032:analysis; D006358:Hot Temperature; D008099:Liver / Q000032:analysis*; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D011965:Receptors, Glucocorticoid / Q000187:drug effects*; D011987:Receptors, Steroid / Q000187:drug effects*; D014020:Tissue Extracts / Q000494:pharmacology*; D014222:Triamcinolone Acetonide / Q000378:metabolism
D011965:Receptors, Glucocorticoid; D011987:Receptors, Steroid; D014020:Tissue Extracts; D014222:Triamcinolone Acetonide