Demonstration that the 90-kilodalton heat shock protein is bound to the glucocorticoid receptor in its 9S nondeoxynucleic acid binding form.
The 9S molybdate-stabilized form of the glucocorticoid receptor of mouse L cell lysates was immunoadsorbed to protein-A-Sepharose with antiserum directed against the 89-kilodalton chicken heat shock protein (anti-hsp89). In order to achieve this, "free" (nonreceptor associated) hsp90 was first separated from the molybdate-stabilized 9S receptor by sucrose gradient sedimentation. Incubation of the 9S [3H]triamcinolone acetonide-labeled receptor peak with anti-hsp89 results in the immune-specific adsorption of 20% of the specifically bound radioactivity and adsorption of the 100-kilodalton receptor protein, as detected by Western-blotting, using the GR49 antireceptor monoclonal antibody as probe. These observations provide the only direct proof that hsp90 is a component of the 9S form of a steroid receptor.
Sanchez
E R
ER
Department of Pharmacology, University of Michigan Medical School, Ann Arbor 48109.
Meshinchi
S
S
Schlesinger
M J
MJ
Pratt
W B
WB
D000818:Animals; D015153:Blotting, Western; D002499:Centrifugation, Density Gradient; D004591:Electrophoresis, Polyacrylamide Gel; D006360:Heat-Shock Proteins / Q000378:metabolism*; D007163:Immunosorbent Techniques; D007739:L Cells; D011965:Receptors, Glucocorticoid / Q000378:metabolism*
D006360:Heat-Shock Proteins; D011965:Receptors, Glucocorticoid