The DNAJB6 and DNAJB8 protein chaperones prevent intracellular aggregation of polyglutamine peptides.
J Biol Chem
; 288(24): 17225-37, 2013 Jun 14.
Article
en En
| MEDLINE
| ID: mdl-23612975
Fragments of proteins containing an expanded polyglutamine (polyQ) tract are thought to initiate aggregation and toxicity in at least nine neurodegenerative diseases, including Huntington's disease. Because proteasomes appear unable to digest the polyQ tract, which can initiate intracellular protein aggregation, preventing polyQ peptide aggregation by chaperones should greatly improve polyQ clearance and prevent aggregate formation. Here we expressed polyQ peptides in cells and show that their intracellular aggregation is prevented by DNAJB6 and DNAJB8, members of the DNAJ (Hsp40) chaperone family. In contrast, HSPA/Hsp70 and DNAJB1, also members of the DNAJ chaperone family, did not prevent peptide-initiated aggregation. Intriguingly, DNAJB6 and DNAJB8 also affected the soluble levels of polyQ peptides, indicating that DNAJB6 and DNAJB8 inhibit polyQ peptide aggregation directly. Together with recent data showing that purified DNAJB6 can suppress fibrillation of polyQ peptides far more efficiently than polyQ expanded protein fragments in vitro, we conclude that the mechanism of DNAJB6 and DNAJB8 is suppression of polyQ protein aggregation by directly binding the polyQ tract.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Fragmentos de Péptidos
/
Péptidos
/
Chaperonas Moleculares
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Proteínas del Choque Térmico HSP40
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Proteínas del Tejido Nervioso
Límite:
Humans
Idioma:
En
Revista:
J Biol Chem
Año:
2013
Tipo del documento:
Article
País de afiliación:
Países Bajos
Pais de publicación:
Estados Unidos