Degradation of p53 by adenovirus E4orf6 and E1B55K proteins occurs via a novel mechanism involving a Cullin-containing complex.
Genes Dev
; 15(23): 3104-17, 2001 Dec 01.
Article
em En
| MEDLINE
| ID: mdl-11731475
ABSTRACT
Although MDM2 plays a major role in regulating the stability of the p53 tumor suppressor protein, other poorly understood MDM2-independent pathways also exist. Human adenoviruses have evolved strategies to regulate p53 function and stability to permit efficient viral replication. One mechanism involves adenovirus E1B55K and E4orf6 proteins, which collaborate to target p53 for degradation. To determine the mechanism of this process, a multiprotein E4orf6-associated complex was purified and shown to contain a novel Cullin-containing E3 ubiquitin ligase that is (1) composed of Cullin family member Cul5, Elongins B and C, and the RING-H2 finger protein Rbx1(ROC1); (2) remarkably similar to the von Hippel-Lindau tumor suppressor and SCF (Skp1-Cul1/Cdc53-F-box) E3 ubiquitin ligase complexes; and (3) capable of stimulating ubiquitination of p53 in vitro in the presence of E1/E2 ubiquitin-activating and -conjugating enzymes. Cullins are activated by NEDD8 modification; therefore, to determine whether Cullin complexes are required for adenovirus-induced p53 degradation, studies were conducted in ts41 Chinese hamster ovary cells that are temperature sensitive for the NEDD8 pathway. E4orf6/E1B55K failed to induce the degradation of p53 at the nonpermissive temperature. Thus, our results identify a novel role for the Cullin-based machinery in regulation of p53.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Proteína Supressora de Tumor p53
/
Proteínas E4 de Adenovirus
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Proteínas E1B de Adenovirus
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Proteínas de Ciclo Celular
Tipo de estudo:
Prognostic_studies
Limite:
Animals
/
Humans
Idioma:
En
Revista:
Genes Dev
Assunto da revista:
BIOLOGIA MOLECULAR
Ano de publicação:
2001
Tipo de documento:
Article
País de afiliação:
Canadá