PDBsum entry 5vso

Chaperone

PDB id: 5vso

Contents

Protein chain

75 a.a.

PDB id:

5vso

Name:

Chaperone

Title:

Nmr structure of ydj1 j-domain, a cytosolic hsp40 from saccharomyces cerevisiae

Structure:

Yeast dnaj protein 1. Chain: a. Fragment: residues 1-70. Synonym: ydj1, mitochondrial protein import protein mas5. Engineered: yes

Source:

Saccharomyces cerevisiae (strain atcc 204508 / s288c). Baker's yeast. Organism_taxid: 559292. Strain: atcc 204508 / s288c. Gene: ydj1, mas5, ynl064c, n2418, ynl2418c. Expressed in: escherichia coli. Expression_system_taxid: 562

NMR struc:

20 models

Authors:

S.J.Ciesielski,M.Tonelli,W.Lee,G.Cornilescu,J.L.Markley,B.A.Schilke, T.Ziegelhoffer,E.A.Craig

Key ref:

B.A.Schilke et al. (2017). Broadening the functionality of a J-protein/Hsp70 molecular chaperone system. PLoS Genet, 13, e1007084. PubMed id: 29084221

Date:

12-May-17 Release date: 01-Nov-17

Protein chain

P25491  (MAS5_YEAST) -  Mitochondrial protein import protein MAS5 from Saccharomyces cerevisiae (strain ATCC 204508 / S288c)

Seq: 409 a.a.

Struc: 75 a.a.

Enzyme reactions

• Enzyme class: E.C.?

PLoS Genet 13:e1007084 (2017)

PubMed id: 29084221

Broadening the functionality of a J-protein/Hsp70 molecular chaperone system.

B.A.Schilke, S.J.Ciesielski, T.Ziegelhoffer, E.Kamiya, M.Tonelli, W.Lee, G.Cornilescu, J.K.Hines, J.L.Markley, E.A.Craig.

ABSTRACT

By binding to a multitude of polypeptide substrates, Hsp70-based molecular chaperone systems perform a range of cellular functions. All J-protein co-chaperones play the essential role, via action of their J-domains, of stimulating the ATPase activity of Hsp70, thereby stabilizing its interaction with substrate. In addition, J-proteins drive the functional diversity of Hsp70 chaperone systems through action of regions outside their J-domains. Targeting to specific locations within a cellular compartment and binding of specific substrates for delivery to Hsp70 have been identified as modes of J-protein specialization. To better understand J-protein specialization, we concentrated on Saccharomyces cerevisiae SIS1, which encodes an essential J-protein of the cytosol/nucleus. We selected suppressors that allowed cells lacking SIS1 to form colonies. Substitutions changing single residues in Ydj1, a J-protein, which, like Sis1, partners with Hsp70 Ssa1, were isolated. These gain-of-function substitutions were located at the end of the J-domain, suggesting that suppression was connected to interaction with its partner Hsp70, rather than substrate binding or subcellular localization. Reasoning that, if YDJ1 suppressors affect Ssa1 function, substitutions in Hsp70 itself might also be able to overcome the cellular requirement for Sis1, we carried out a selection for SSA1 suppressor mutations. Suppressing substitutions were isolated that altered sites in Ssa1 affecting the cycle of substrate interaction. Together, our results point to a third, additional means by which J-proteins can drive Hsp70's ability to function in a wide range of cellular processes-modulating the Hsp70-substrate interaction cycle.