Fusion protein analysis reveals the precise regulation between Hsp70 and Hsp100 during protein disaggregation.
Sci Rep
; 7(1): 8648, 2017 08 17.
Article
em En
| MEDLINE
| ID: mdl-28819163
ABSTRACT
ClpB, a bacterial Hsp100, is a ring-shaped AAA+ chaperone that can reactivate aggregated proteins in cooperation with DnaK, a bacterial Hsp70, and its co-factors. ClpB subunits comprise two AAA+ modules with an interstitial rod-shaped M-domain. The M-domain regulates ClpB ATPase activity and interacts directly with the DnaK nucleotide-binding domain (NBD). Here, to clarify how these functions contribute to the disaggregation process, we constructed ClpB, DnaK, and aggregated YFP fusion proteins in various combinations. Notably, i) DnaK activates ClpB only when the DnaK substrate-binding domain (SBD) is in the closed conformation, affording high DnaK-peptide affinity; ii) although NBD alone can activate ClpB, SBD is required for disaggregation; and iii) tethering aggregated proteins to the activated ClpB obviates SBD requirements. These results indicate that DnaK activates ClpB only when the SBD tightly holds aggregated proteins adjacent to ClpB for effective disaggregation.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Proteínas de Choque Térmico HSP70
/
Proteínas de Choque Térmico
Tipo de estudo:
Prognostic_studies
Idioma:
En
Ano de publicação:
2017
Tipo de documento:
Article