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Functionality of Class A and Class B J-protein co-chaperones with Hsp70.

ABSTRACT: At their C-termini, cytosolic Hsp70s have an EEVD tetrapeptide that interacts with J-protein co-chaperones of the B, but not A, class. This interaction is required for partnering with yeast B-type J-proteins in protein folding. Here we report conservation of this feature. Human B-type J-proteins also have a stringent EEVD requirement. Human A-type J-proteins function less well than their yeast orthologs with Hsp70?EEVD. Changes in the zinc binding domain, a domain absent in B-type J-proteins, overcomes this partial EEVD dependence. Our results suggest that the structurally similar A- and B-class J-proteins of the cytosol have evolved conserved, yet distinct, features that enhance specialized functionality of Hsp70 machinery.

SUBMITTER: Yu HY

PROVIDER: S-EPMC4570866 | biostudies-literature | 2015 Sep

REPOSITORIES: biostudies-literature

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Functionality of Class A and Class B J-protein co-chaperones with Hsp70.

Yu Hyun Young HY Ziegelhoffer Thomas T Craig Elizabeth A EA

FEBS letters 20150803 19 Pt B

At their C-termini, cytosolic Hsp70s have an EEVD tetrapeptide that interacts with J-protein co-chaperones of the B, but not A, class. This interaction is required for partnering with yeast B-type J-proteins in protein folding. Here we report conservation of this feature. Human B-type J-proteins also have a stringent EEVD requirement. Human A-type J-proteins function less well than their yeast orthologs with Hsp70ΔEEVD. Changes in the zinc binding domain, a domain absent in B-type J-proteins, ov ...[more]

PMID: 26247431

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