Sgt1p is a unique co-chaperone that acts as a client adaptor to link Hsp90 to Skp1p

Michael G. Catlett, Kenneth B. Kaplan

Research output: Contribution to journalArticle

92 Citations (Scopus)

Abstract

Sgt1p is a conserved, essential protein required for kinetochore assembly in both yeast and animal cells. Sgt1p has homology to both TPR and p23 domains, sequences often found in proteins that interact with and regulate the molecular chaperone, Hsp90. The presence of these domains and the recent findings that Sgt1p interacts with Hsp90 has led to the speculation that Sgt1p and Hsp90 form a co-chaperone complex. To test this possibility, we have used purified recombinant proteins to characterize the in vitro interactions between yeast Sgt1p and Hsp82p (an Hsp90 homologue in yeast). We show that Sgt1p interacts directly with Hsp82p via its p23 homology region in a nucleotide-dependent manner. However, Sgt1p binding does not alter the enzymatic activity of Hsp82p, suggesting that it is distinct from other co-chaperones. We find that Sgt1p can form a ternary chaperone complex with Hsp82p and Sti1p, a well characterized Hsp90 co-chaperone. Sgt1p interacts with its binding partner Skp1p through its TPR domains and links Skp1p to the core Hsp82p-Sti1p co-chaperone complex. The multidomain nature of Sgt1p and its ability to bridge the interaction between Skp1p and Hsp82p argue that Sgt1p acts as a "client adaptor" recruiting specific clients to Hsp82p co-chaperone complexes.

Original languageEnglish (US)
Pages (from-to)33739-33748
Number of pages10
JournalJournal of Biological Chemistry
Volume281
Issue number44
DOIs
StatePublished - Nov 3 2006

Fingerprint

Yeast
Yeasts
Kinetochores
Molecular Chaperones
Recombinant Proteins
Animals
Proteins
Nucleotides
Cells
In Vitro Techniques

ASJC Scopus subject areas

  • Biochemistry

Cite this

Sgt1p is a unique co-chaperone that acts as a client adaptor to link Hsp90 to Skp1p. / Catlett, Michael G.; Kaplan, Kenneth B.

In: Journal of Biological Chemistry, Vol. 281, No. 44, 03.11.2006, p. 33739-33748.

Research output: Contribution to journalArticle

Catlett, Michael G. ; Kaplan, Kenneth B. / Sgt1p is a unique co-chaperone that acts as a client adaptor to link Hsp90 to Skp1p. In: Journal of Biological Chemistry. 2006 ; Vol. 281, No. 44. pp. 33739-33748.
@article{218debb468f7431c9044d0e59c5b51c8,
title = "Sgt1p is a unique co-chaperone that acts as a client adaptor to link Hsp90 to Skp1p",
abstract = "Sgt1p is a conserved, essential protein required for kinetochore assembly in both yeast and animal cells. Sgt1p has homology to both TPR and p23 domains, sequences often found in proteins that interact with and regulate the molecular chaperone, Hsp90. The presence of these domains and the recent findings that Sgt1p interacts with Hsp90 has led to the speculation that Sgt1p and Hsp90 form a co-chaperone complex. To test this possibility, we have used purified recombinant proteins to characterize the in vitro interactions between yeast Sgt1p and Hsp82p (an Hsp90 homologue in yeast). We show that Sgt1p interacts directly with Hsp82p via its p23 homology region in a nucleotide-dependent manner. However, Sgt1p binding does not alter the enzymatic activity of Hsp82p, suggesting that it is distinct from other co-chaperones. We find that Sgt1p can form a ternary chaperone complex with Hsp82p and Sti1p, a well characterized Hsp90 co-chaperone. Sgt1p interacts with its binding partner Skp1p through its TPR domains and links Skp1p to the core Hsp82p-Sti1p co-chaperone complex. The multidomain nature of Sgt1p and its ability to bridge the interaction between Skp1p and Hsp82p argue that Sgt1p acts as a {"}client adaptor{"} recruiting specific clients to Hsp82p co-chaperone complexes.",
author = "Catlett, {Michael G.} and Kaplan, {Kenneth B.}",
year = "2006",
month = "11",
day = "3",
doi = "10.1074/jbc.M603847200",
language = "English (US)",
volume = "281",
pages = "33739--33748",
journal = "Journal of Biological Chemistry",
issn = "0021-9258",
publisher = "American Society for Biochemistry and Molecular Biology Inc.",
number = "44",

}

TY - JOUR

T1 - Sgt1p is a unique co-chaperone that acts as a client adaptor to link Hsp90 to Skp1p

AU - Catlett, Michael G.

AU - Kaplan, Kenneth B.

PY - 2006/11/3

Y1 - 2006/11/3

N2 - Sgt1p is a conserved, essential protein required for kinetochore assembly in both yeast and animal cells. Sgt1p has homology to both TPR and p23 domains, sequences often found in proteins that interact with and regulate the molecular chaperone, Hsp90. The presence of these domains and the recent findings that Sgt1p interacts with Hsp90 has led to the speculation that Sgt1p and Hsp90 form a co-chaperone complex. To test this possibility, we have used purified recombinant proteins to characterize the in vitro interactions between yeast Sgt1p and Hsp82p (an Hsp90 homologue in yeast). We show that Sgt1p interacts directly with Hsp82p via its p23 homology region in a nucleotide-dependent manner. However, Sgt1p binding does not alter the enzymatic activity of Hsp82p, suggesting that it is distinct from other co-chaperones. We find that Sgt1p can form a ternary chaperone complex with Hsp82p and Sti1p, a well characterized Hsp90 co-chaperone. Sgt1p interacts with its binding partner Skp1p through its TPR domains and links Skp1p to the core Hsp82p-Sti1p co-chaperone complex. The multidomain nature of Sgt1p and its ability to bridge the interaction between Skp1p and Hsp82p argue that Sgt1p acts as a "client adaptor" recruiting specific clients to Hsp82p co-chaperone complexes.

AB - Sgt1p is a conserved, essential protein required for kinetochore assembly in both yeast and animal cells. Sgt1p has homology to both TPR and p23 domains, sequences often found in proteins that interact with and regulate the molecular chaperone, Hsp90. The presence of these domains and the recent findings that Sgt1p interacts with Hsp90 has led to the speculation that Sgt1p and Hsp90 form a co-chaperone complex. To test this possibility, we have used purified recombinant proteins to characterize the in vitro interactions between yeast Sgt1p and Hsp82p (an Hsp90 homologue in yeast). We show that Sgt1p interacts directly with Hsp82p via its p23 homology region in a nucleotide-dependent manner. However, Sgt1p binding does not alter the enzymatic activity of Hsp82p, suggesting that it is distinct from other co-chaperones. We find that Sgt1p can form a ternary chaperone complex with Hsp82p and Sti1p, a well characterized Hsp90 co-chaperone. Sgt1p interacts with its binding partner Skp1p through its TPR domains and links Skp1p to the core Hsp82p-Sti1p co-chaperone complex. The multidomain nature of Sgt1p and its ability to bridge the interaction between Skp1p and Hsp82p argue that Sgt1p acts as a "client adaptor" recruiting specific clients to Hsp82p co-chaperone complexes.

UR - http://www.scopus.com/inward/record.url?scp=33845959149&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=33845959149&partnerID=8YFLogxK

U2 - 10.1074/jbc.M603847200

DO - 10.1074/jbc.M603847200

M3 - Article

VL - 281

SP - 33739

EP - 33748

JO - Journal of Biological Chemistry

JF - Journal of Biological Chemistry

SN - 0021-9258

IS - 44

ER -