J. Biochem, 1994, Vol. 115, No. 3 486-492
© 1994 Japanese Biochemical Society
research-article |
Association of the ß
Subunits of Trimeric GTP-Binding Proteins with 90-kDa Heat Shock Protein, hsp901
*Department of Life Science, Tokyo Institute of Technology 4259 Nagatsuta, Midori-ku, Yokohama 227
**Department of Physiological Chemistry, Faculty of Pharmaceutical Sciences, The University of Tokyo 7-3-1 Hongo, Bunkyo-ku, Tokyo 113
2To whom correspondence should be addressed.
GTP-binding proteins (G proteins), predominantly located at the inner surface of the plasma membranes of mammalian cells, dissociate into their constituent 
and ß
subunits upon stimulation of G protein-coupled receptors by agonists. In the present studies, cytoplasmic proteins which might have an affinity for the dissociated ß subunits were investigated by means of ß subunit-immobilized affinity-column (ß-immobilized column) chromatography. When soluble fractions obtained from various materials including rat liver, bovine brain, and HL-60 cells were applied to a ß-immobilized column, some proteins were specifically eluted from the column with high-salt and detergent-containing solutions. One of the ß subunit-binding proteins, of which the molecular weight was approximately 93, 000 on SDS-PAGE, appeared to be commonly present in all tissues tested. The 93-kDa ß-binding protein was identified as 90-kDa heat shock protein, hsp90, based on the findings of its partial amino acid sequences and its immunoreactivity to a monoclonal anti-hsp90 antibody. The brain hsp90 inhibited ß-supported pertussis toxin-catalyzed ADP-ribosylation of a subunits. The hsp90 was also capable of binding to ß subunits which had been reconstituted into phospholipid vesicles. The binding of hsp90 to ß subunits was inhibited by the addition of GDP-bound subunits, but not by GTPS-bound ones. These results suggested that hsp90 could associate functionally with free By subunits dissociated from trimeric G proteins in vitro.
1This work was supported in part by research grants from the Scientific Research Fund of the Ministry of Education, Science, and Culture of Japan, and the Human Frontier Science Program.
CiteULike 
Connotea 
Del.icio.us What's this?
This article has been cited by other articles:
|
|
 |
|
  D. J. Dupre, M. Robitaille, M. Richer, N. Ethier, A. M. Mamarbachi, and T. E. Hebert Dopamine Receptor-interacting Protein 78 Acts as a Molecular Chaperone for G{gamma} Subunits before Assembly with Gbeta J. Biol. Chem., May 4, 2007; 282(18): 13703 - 13715. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. A. Wells, J. Dingus, and J. D. Hildebrandt Role of the Chaperonin CCT/TRiC Complex in G Protein beta{gamma}-Dimer Assembly J. Biol. Chem., July 21, 2006; 281(29): 20221 - 20232. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 W. B. Pratt and D. O. Toft Regulation of Signaling Protein Function and Trafficking by the hsp90/hsp70-Based Chaperone Machinery Experimental Biology and Medicine, February 1, 2003; 228(2): 111 - 133. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. H. Davies, Y.-M. Ning, and E. R. Sanchez A New First Step in Activation of Steroid Receptors. HORMONE-INDUCED SWITCHING OF FKBP51 AND FKBP52 IMMUNOPHILINS J. Biol. Chem., February 8, 2002; 277(7): 4597 - 4600. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
R. Vaiskunaite, T. Kozasa, and T. A. Voyno-Yasenetskaya Interaction between the Galpha Subunit of Heterotrimeric G12 Protein and Hsp90 Is Required for Galpha 12 Signaling J. Biol. Chem., November 30, 2001; 276(49): 46088 - 46093. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
L. Busconi, J. Guan, and B. M. Denker Degradation of Heterotrimeric Galpha o Subunits via the Proteosome Pathway Is Induced by the hsp90-specific Compound Geldanamycin J. Biol. Chem., January 21, 2000; 275(3): 1565 - 1569. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 W. B. Pratt and D. O. Toft Steroid Receptor Interactions with Heat Shock Protein and Immunophilin Chaperones Endocr. Rev., June 1, 1997; 18(3): 306 - 360. [Abstract] [Full Text]
|
|
|
|
 |
|
 X Meng, J Devin, W. Sullivan, D Toft, E. Baulieu, and M. Catelli Mutational analysis of Hsp90 alpha dimerization and subcellular localization: dimer disruption does not impede ""in vivo' interaction with estrogen receptor J. Cell Sci., January 7, 1996; 109(7): 1677 - 1687. [Abstract] [PDF]
|
|
|
|
|
|
S. P. Bohen and S. P. Bohen Hsp90 Mutants Disrupt Glucocorticoid Receptor Ligand Binding and Destabilize Aporeceptor Complexes J. Biol. Chem., December 8, 1995; 270(49): 29433 - 29438. [Abstract] [Full Text] [PDF]
|
|