title: The involvement of p23, hsp90, and immunophilins in the assembly of progesterone receptor complexes.
abstract: To better understand the assembly mechanism for the progesterone receptor (PR), we have developed cell-free systems for studying interactions of PR, hsp90, and other associated proteins. When PR is incubated in rabbit reticulocyte lysate, its association with hsp90, hsp70, the three immunophilins FKBP54, FKBP52 and CyP-40, and with p23 is observed. These interactions require ATP/Mg2+ and when ATP is limiting the PR complex is altered to one containing the proteins p60 and p48, but lacking immunophilins and p23. We have studied two pre-formed hsp90 complexes that may participate in the assembly of PR complexes. One contains hsp90 bound to hsp70 and p60 and this complex forms spontaneously in the absence of ATP. A second complex contains hsp90 bound to p23 plus the three immunophilins and some hsp70. The formation of this complex requires ATP. In further studies we have shown that purified hsp90 can bind to purified p23 and this interaction requires both ATP and molybdate. This explains, in part, the known effects of ATP and molybdate on assembly of PR complexes.
authors.affiliation: Department of Biochemistry and Molecular Biology, Mayo Graduate School, Rochester, MN 55905, USA.
authors.forename: J
authors.initials: J
authors.lastname: Johnson
authors.forename: R
authors.initials: R
authors.lastname: Corbisier
authors.forename: B
authors.initials: B
authors.lastname: Stensgard
authors.forename: D
authors.initials: D
authors.lastname: Toft
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D000591:Amino Acid Isomerases / Q000378:metabolism*; D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D002352:Carrier Proteins / Q000378:metabolism*; D002474:Cell-Free System; D002645:Chickens; D000081406:Peptidyl-Prolyl Isomerase F; D021983:Cyclophilins; D004268:DNA-Binding Proteins / Q000378:metabolism*; D018840:HSP70 Heat-Shock Proteins / Q000378:metabolism; D018841:HSP90 Heat-Shock Proteins / Q000276:immunology / Q000378:metabolism*; D006360:Heat-Shock Proteins / Q000378:metabolism*; D006801:Humans; D019746:Intramolecular Oxidoreductases; D046911:Macromolecular Substances; D051379:Mice; D018832:Molecular Chaperones; D008982:Molybdenum / Q000378:metabolism; D019696:Peptidylprolyl Isomerase; D010750:Phosphoproteins / Q000378:metabolism*; D000071876:Prostaglandin-E Synthases; D011817:Rabbits; D011980:Receptors, Progesterone / Q000378:metabolism*; D012156:Reticulocytes; D022021:Tacrolimus Binding Proteins
chemical_list: D000911:Antibodies, Monoclonal; D002352:Carrier Proteins; D000081406:Peptidyl-Prolyl Isomerase F; D004268:DNA-Binding Proteins; D018840:HSP70 Heat-Shock Proteins; D018841:HSP90 Heat-Shock Proteins; D006360:Heat-Shock Proteins; D046911:Macromolecular Substances; D018832:Molecular Chaperones; C000631446:PPIF protein, mouse; D010750:Phosphoproteins; D011980:Receptors, Progesterone; C079373:STIP1 protein, human; C489791:Stip1 protein, mouse; C044659:molybdate; D008982:Molybdenum; D000255:Adenosine Triphosphate; D000591:Amino Acid Isomerases; D021983:Cyclophilins; D022021:Tacrolimus Binding Proteins; D019696:Peptidylprolyl Isomerase; D019746:Intramolecular Oxidoreductases; C490849:PTGES3 protein, human; D000071876:Prostaglandin-E Synthases