![]() |
|
|
Vol. 19, Issue 12, 5249-5258, December 2008
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Department of Microbiology, Molecular Biology and Biochemistry and the Center for Reproductive Biology, University of Idaho, Moscow, ID 83844-3052
Submitted April 28, 2008;
Revised August 26, 2008;
Accepted September 24, 2008
Monitoring Editor: Jonathan S. Weissman
Ydj1 of Saccharomyces cerevisiae is an abundant cytosolic Hsp40, or J-type, molecular chaperone. Ydj1 cooperates with Hsp70 of the Ssa family in the translocation of preproteins to the ER and mitochondria and in the maturation of Hsp90 client proteins. The substrate-binding domain of Ydj1 directly interacts with steroid receptors and is required for the activity of diverse Hsp90-dependent client proteins. However, the effect of Ydj1 alteration on client interaction was unknown. We analyzed the in vivo interaction of Ydj1 with the protein kinase Ste11 and the glucocorticoid receptor. Amino acid alterations in the proposed client-binding domain or zinc-binding domain had minor effects on the physical interaction of Ydj1 with both clients. However, alteration of the carboxy-terminal farnesylation signal disrupted the functional and physical interaction of Ydj1 and Hsp90 with both clients. Similar effects were observed upon deletion of RAM1, which encodes one of the subunits of yeast farnesyltransferase. Our results indicate that farnesylation is a major factor contributing to the specific requirement for Ydj1 in promoting proper regulation and activation of diverse Hsp90 clients.
Address correspondence to: Jill L. Johnson (jilljohn{at}uidaho.edu)
Abbreviations used: Hsp, heat-shock protein; GR, glucocorticoid receptor; SBD, substrate-binding domain.
Related articles in Mol. Biol. Cell:
This article has been cited by other articles:
![]() |
P. Kota, D. W. Summers, H.-Y. Ren, D. M. Cyr, and N. V. Dokholyan Identification of a consensus motif in substrates bound by a Type I Hsp40 PNAS, July 7, 2009; 106(27): 11073 - 11078. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. W. Summers, P. M. Douglas, H.-Y. Ren, and D. M. Cyr The Type I Hsp40 Ydj1 Utilizes a Farnesyl Moiety and Zinc Finger-like Region to Suppress Prion Toxicity J. Biol. Chem., February 6, 2009; 284(6): 3628 - 3639. [Abstract] [Full Text] [PDF] |
||||