The molecular chaperone Hsp90 plays a role in the assembly and maintenance of the 26S proteasome.
- Resource Type
- Article
- Authors
- J. Imai; M. Maruya; H. Yashiroda; I. Yahara; K. Tanaka
- Source
- EMBO Journal. 7/15/2003, Vol. 22 Issue 14, p3557-3567. 11p.
- Subject
- *MOLECULAR chaperones
*CELLULAR signal transduction
- Language
- ISSN
- 0261-4189
Hsp90 has a diverse array of cellular roles including protein folding, stress response and signal transduction. Herein we report a novel function for Hsp90 in the ATP-dependent assembly of the 26S proteasome. Functional loss of Hsp90 using a temperature-sensitive mutant in yeast caused dissociation of the 26S proteasome. Conversely, these dissociated constituents reassembled in Hsp90-dependent fashion both in vivo and in vitro; the process required ATP-hydrolysis and was suppressed by the Hsp90 inhibitor geldanamycin. We also found genetic interactions between Hsp90 and several proteasomal Rpn (Regulatory particle non-ATPase subunit) genes, emphasizing the importance of Hsp90 to the integrity of the 26S proteasome. Our results indicate that Hsp90 interacts with the 26S proteasome and plays a principal role in the assembly and maintenance of the 26S proteasome. [ABSTRACT FROM AUTHOR]