Relationship of the 90-kDa murine heat shock protein to the untransformed and transformed states of the L cell glucocorticoid receptor.
Incubation of molybdate-stabilized L cell cytosol with a monoclonal antibody directed against the 100-kDa glucocorticoid-binding protein causes the immune-specific adsorption to protein A-Sepharose of both the 100-kDa glucocorticoid receptor and the 90-kDa murine heat shock protein (hsp90) (Sanchez, E. R., Toft, D. O., Schlesinger, M. J., and Pratt, W. B. (1985) J. Biol. Chem. 260, 12398-12401). When the glucocorticoid receptor in cytosol is transformed to the DNA-binding state, hsp90 dissociates. In this paper, we show that temperature-mediated dissociation of hsp90 from the receptor is a hormone-dependent event in the same manner as temperature-mediated transformation to the DNA-binding state. In contrast to temperature-mediated transformation, ammonium sulfate causes both dissociation of hsp90 from the receptor and conversion of the receptor to the DNA-binding form in a manner that does not require the presence of steroid. The untransformed form of the glucocorticoid receptor and the strongly negatively charged hsp90 protein behave similarly on DEAE-cellulose chromatography, suggesting that the hsp90 component may contribute significantly to the net negative charge behavior of the non-DNA-binding form of the receptor complex.
Sanchez
E R
ER
Meshinchi
S
S
Tienrungroj
W
W
Schlesinger
M J
MJ
Toft
D O
DO
Pratt
W B
WB
D000645:Ammonium Sulfate / Q000494:pharmacology; D000818:Animals; D011232:Chemical Precipitation; D002848:Chromatography, DEAE-Cellulose; D003600:Cytosol / Q000378:metabolism; D004247:DNA / Q000378:metabolism*; D006360:Heat-Shock Proteins / Q000378:metabolism*; D007163:Immunosorbent Techniques; D007739:L Cells; D051379:Mice; D008982:Molybdenum / Q000494:pharmacology; D011965:Receptors, Glucocorticoid / Q000187:drug effects / Q000378:metabolism*; D013696:Temperature; D014222:Triamcinolone Acetonide / Q000378:metabolism
D006360:Heat-Shock Proteins; D011965:Receptors, Glucocorticoid; C044659:molybdate; D008982:Molybdenum; D004247:DNA; D014222:Triamcinolone Acetonide; D000645:Ammonium Sulfate