Two DNA-bound E2 dimers are required for strong transcriptional activation and for cooperation with cellular factors in most cells.
New Biol
; 3(5): 498-509, 1991 May.
Article
en En
| MEDLINE
| ID: mdl-1653009
ABSTRACT
The E2 transcriptional activator encoded by papillomaviruses binds as a dimer to the palindromic sequence ACCGNNNNCGGT present in several copies in the viral genomes. We show that strong activation requires that a minimum of two E2 binding sites are actually occupied by the protein. Studies with constructs bearing two E2 sites separated by variable lengths of DNA showed that there is no stereospecific constraint for E2 homosynergy. The capacity of E2 to cooperate with cellular factors interacting with the promoter/enhancer sequences of the genomes of human papilloma virus types 16, 18, or 33 was further investigated. In epithelial cells, one E2 dimer could not cooperate with the AP1 complex, the glucocorticoid receptor, or the NF1/K factor, whereas several E2 dimers could. These results lead to the notion of the "functional E2 tetramer" as the unit for strong transcriptional activation by E2 and for cooperativity with other cellular factors in this process. Finally, our results suggest that activators such as E2 or the glucocorticoid receptor may interact with partially different targets in the transcriptional machinery.
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Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Papillomaviridae
/
Proteínas Virales
/
Regulación Viral de la Expresión Génica
/
Proteínas Oncogénicas Virales
/
Elementos de Facilitación Genéticos
/
Proteínas de Unión al ADN
/
Proteínas Reguladoras y Accesorias Virales
Límite:
Animals
/
Humans
Idioma:
En
Revista:
New Biol
Asunto de la revista:
BIOLOGIA MOLECULAR
/
BIOTECNOLOGIA
Año:
1991
Tipo del documento:
Article
País de afiliación:
Francia