The hsp90-FKBP52 complex links the mineralocorticoid receptor to motor proteins and persists bound to the receptor in early nuclear events

• Autores: Galigniana, M.D.; Erlejman, A.G.; Monte, M.; Gomez-Sanchez, C.; Piwien-Pilipuk, G.
• Año de publicación: 2010
• Idioma: inglés
• Tipo de recurso: artículo
• Fuente: Mol. Cell. Biol. 2010;30(5):1285-1298
• Materia: aldosterone; dynein adenosine triphosphatase; fk 506 binding protein; heat shock protein 90; immunophilin; mineralocorticoid receptor; molecular motor; protein fkbp52; tubulin; unclassified drug; animal cell; article; controlled study; human; human cell; mouse; nonhuman; priority journal; protein cross linking; protein domain; protein localization; protein protein interaction; tetratricopeptide repeat; Active Transport, Cell Nucleus; Animals; Cell Line; Cell Nucleus; CHO Cells; Cricetinae; Cricetulus; Dyneins; HSP90 Heat-Shock Proteins; Humans; Immunophilins; Mice; Microtubules; Molecular Motor Proteins; Multiprotein Complexes; NIH 3T3 Cells; Nuclear Pore; Nuclear Pore Complex Proteins; Protein Binding; Protein Stability; Protein Structure, Tertiary; Rats; Receptors, Mineralocorticoid; Recombinant Proteins; Tacrolimus Binding Proteins
• Institución: Universidad Nacional de Buenos Aires. Facultad de Ciencias Exactas y Naturales

In this study, we demonstrate that the subcellular localization of the mineralocorticoid receptor (MR) is regulated by tetratricopeptide domain (TPR) proteins. The high-molecular-weight immunophilin (IMM) FKBP52 links the MR-hsp90 complex to dynein/dynactin motors favoring the cytoplasmic transport of MR to the nucleus. Replacement of this hsp90-binding IMM by FKBP51 or the TPR peptide favored the cytoplasmic localization of MR. The complete movement machinery, including dynein and tubulin, could be recovered from paclitaxel/GTP-stabilized cytosol and was fully reassembled on stripped MR immune pellets. The whole MR-hsp90-based heterocomplex was transiently recovered in the soluble fraction of the nucleus after 10 min of incubation with aldosterone. Moreover, cross-linked MR-hsp90 heterocomplexes accumulated in the nucleus in a hormone-dependent manner, demonstrating that the heterocomplex can pass undissociated through the nuclear pore. On the other hand, a peptide that comprises the DNA-binding domain of MR impaired the nuclear export of MR, suggesting the involvement of this domain in the process. This study represents the first report describing the entire molecular system that commands MR nucleocytoplasmic trafficking and proposes that the MR-hsp90-TPR protein heterocomplex is dissociated in the nucleus rather than in the cytoplasm. Copyright © 2010, American Society for Microbiology. All Rights Reserved.
Fil:Monte, M. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.