The UNC-45 chaperone mediates sarcomere assembly through myosin degradation in Caenorhabditis elegans.
J Cell Biol
; 177(2): 205-10, 2007 Apr 23.
Article
em En
| MEDLINE
| ID: mdl-17438072
ABSTRACT
Myosin motors are central to diverse cellular processes in eukaryotes. Homologues of the myosin chaperone UNC-45 have been implicated in the assembly and function of myosin-containing structures in organisms from fungi to humans. In muscle, the assembly of sarcomeric myosin is regulated to produce stable, uniform thick filaments. Loss-of-function mutations in Caenorhabditis elegans UNC-45 lead to decreased muscle myosin accumulation and defective thick filament assembly, resulting in paralyzed animals. We report that transgenic worms overexpressing UNC-45 also display defects in myosin assembly, with decreased myosin content and a mild paralysis phenotype. We find that the reduced myosin accumulation is the result of degradation through the ubiquitin/proteasome system. Partial proteasome inhibition is able to restore myosin protein and worm motility to nearly wild-type levels. These findings suggest a mechanism in which UNC-45-related proteins may contribute to the degradation of myosin in conditions such as heart failure and muscle wasting.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Sarcômeros
/
Miosinas
/
Caenorhabditis elegans
/
Chaperonas Moleculares
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Proteínas de Caenorhabditis elegans
Limite:
Animals
Idioma:
En
Revista:
J Cell Biol
Ano de publicação:
2007
Tipo de documento:
Article
País de afiliação:
Estados Unidos