4RWU

J-domain of Sis1 protein, Hsp40 co-chaperone from Saccharomyces cerevisiae


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.25 Å
  • R-Value Free: 0.149 
  • R-Value Work: 0.122 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Roles of intramolecular and intermolecular interactions in functional regulation of the Hsp70 J-protein co-chaperone Sis1.

Yu, H.Y.Ziegelhoffer, T.Osipiuk, J.Ciesielski, S.J.Baranowski, M.Zhou, M.Joachimiak, A.Craig, E.A.

(2015) J.Mol.Biol. 427: 1632-1643

  • DOI: 10.1016/j.jmb.2015.02.007

  • PubMed Abstract: 
  • Unlike other Hsp70 molecular chaperones, those of the eukaryotic cytosol have four residues, EEVD, at their C-termini. EEVD(Hsp70) binds adaptor proteins of the Hsp90 chaperone system and mitochondrial membrane preprotein receptors, thereby facilitat ...

    Unlike other Hsp70 molecular chaperones, those of the eukaryotic cytosol have four residues, EEVD, at their C-termini. EEVD(Hsp70) binds adaptor proteins of the Hsp90 chaperone system and mitochondrial membrane preprotein receptors, thereby facilitating processing of Hsp70-bound clients through protein folding and translocation pathways. Among J-protein co-chaperones functioning in these pathways, Sis1 is unique, as it also binds the EEVD(Hsp70) motif. However, little is known about the role of the Sis1:EEVD(Hsp70) interaction. We found that deletion of EEVD(Hsp70) abolished the ability of Sis1, but not the ubiquitous J-protein Ydj1, to partner with Hsp70 in in vitro protein refolding. Sis1 co-chaperone activity with Hsp70∆EEVD was restored upon substitution of a glutamic acid of the J-domain. Structural analysis revealed that this key glutamic acid, which is not present in Ydj1, forms a salt bridge with an arginine of the immediately adjacent glycine-rich region. Thus, restoration of Sis1 in vitro activity suggests that intramolecular interactions between the J-domain and glycine-rich region control co-chaperone activity, which is optimal only when Sis1 interacts with the EEVD(Hsp70) motif. However, we found that disruption of the Sis1:EEVD(Hsp70) interaction enhances the ability of Sis1 to substitute for Ydj1 in vivo. Our results are consistent with the idea that interaction of Sis1 with EEVD(Hsp70) minimizes transfer of Sis1-bound clients to Hsp70s that are primed for client transfer to folding and translocation pathways by their preassociation with EEVD binding adaptor proteins. These interactions may be one means by which cells triage Ydj1- and Sis1-bound clients to productive and quality control pathways, respectively.


    Organizational Affiliation

    Department of Biochemistry, University of Wisconsin-Madison, 433 Babcock Drive, Madison, WI 53706, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Protein SIS1
A
92Saccharomyces cerevisiae (strain ATCC 204508 / S288c)Gene Names: SIS1
Find proteins for P25294 (Saccharomyces cerevisiae (strain ATCC 204508 / S288c))
Go to UniProtKB:  P25294
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.25 Å
  • R-Value Free: 0.149 
  • R-Value Work: 0.122 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 31.645α = 90.00
b = 43.564β = 90.00
c = 65.572γ = 90.00
Software Package:
Software NamePurpose
SBC-Collectdata collection
SCALEPACKdata scaling
PDB_EXTRACTdata extraction
DENZOdata reduction
REFMACrefinement
HKL-3000data scaling
PHASERphasing
HKL-3000data reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2014-12-17
    Type: Initial release
  • Version 1.1: 2015-09-09
    Type: Database references
  • Version 1.2: 2017-11-22
    Type: Refinement description