The Hsp40 J-domain stimulates Hsp70 when tethered by the client to the ATPase domain.
J Biol Chem
; 285(28): 21679-88, 2010 Jul 09.
Article
em En
| MEDLINE
| ID: mdl-20448033
The Escherichia coli Hsp40 DnaJ uses its J-domain (Jd) to couple ATP hydrolysis and client protein capture in Hsp70 DnaK. Fusion of the Jd to peptide p5 (as in Jdp5) dramatically increases the apparent affinity of the p5 moiety for DnaK in the presence of ATP, and Jdp5 stimulates ATP hydrolysis in DnaK by several orders of magnitude. NMR experiments with [(15)N]Jdp5 demonstrated that the peptide tethers the Jd to the ATPase domain. Thus, ATP hydrolysis and client protein binding in DnaK are coupled principally through the association of the client with DnaJ. Overexpression of a recombinant Jd was specifically toxic to cells that simultaneously expressed DnaK. No toxicity was observed when overexpressing Jdp5 or mutant Jd or when co-overexpressing the Jd and the nucleotide exchange factor GrpE. The results suggest that the Jd shifts DnaK to a client-bound form by stimulating the DnaK ATPase but only when the Jd is brought to DnaK by a client-Hsp40 complex.
Texto completo:
1
Coleções:
01-internacional
Contexto em Saúde:
3_ND
Base de dados:
MEDLINE
Assunto principal:
Adenosina Trifosfatases
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Proteínas de Choque Térmico HSP70
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Escherichia coli
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Proteínas de Choque Térmico HSP40
Idioma:
En
Revista:
J Biol Chem
Ano de publicação:
2010
Tipo de documento:
Article