Promoter-binding and repression of PDGFRB by c-Myc are separable activities.
Nucleic Acids Res
; 32(11): 3462-8, 2004.
Article
en En
| MEDLINE
| ID: mdl-15226411
ABSTRACT
The c-Myc transcription factor represses the mRNA expression of the platelet-derived growth factor receptor beta gene (PDGFRB). Using chromatin immunoprecipitation, we show that c-Myc binds to the proximal promoter of the PDGFRB gene in proliferating rat fibroblasts. Interestingly, mutant c-Myc proteins that are unable to repress PDGFRB gene expression, c-Myc(dBR) and c-Myc(d106-143), are still able to bind to the promoter in vivo. Hence, promoter-binding and repression of PDGFRB by c-Myc are separable activities. We also show that Myc repression of PDGFRB is not dependent on previously described or known transactivator-binding regions, suggesting Myc may be recruited to the promoter by multiple or yet unidentified transcription factors. In the presence of intact promoter-binding by Myc, trichostatin A (TSA) can block Myc repression of PDGFRB in vivo, again demonstrating that promoter-binding and repression are separable. Taken together, we hypothesize that Myc repression of PDGFRB expression occurs by a multi-step mechanism in which repression is initiated after Myc is recruited to the promoter.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Proteínas Represoras
/
Proteínas Proto-Oncogénicas c-myc
/
Regiones Promotoras Genéticas
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Receptor beta de Factor de Crecimiento Derivado de Plaquetas
Límite:
Animals
Idioma:
En
Revista:
Nucleic Acids Res
Año:
2004
Tipo del documento:
Article
País de afiliación:
Canadá