Ecdysone regulation of the Drosophila Sgs-4 gene is mediated by the synergistic action of ecdysone receptor and SEBP 3.
EMBO J
; 14(4): 716-26, 1995 Feb 15.
Article
em En
| MEDLINE
| ID: mdl-7882975
ABSTRACT
The steroid hormone 20-hydroxyecdysone controls both induction and repression of the Drosophila 'intermolt gene' Sgs-4. We show here that the ecdysone receptor binds to two sites, element I and element II, in the regulatory region of Sgs-4. A functional analysis revealed that element II appears to be of no importance for Sgs-4 expression, while element I proved to be an ecdysone response element that is necessary, but not sufficient, for induction of Sgs-4 expression. Our results provide no evidence that repression of Sgs-4 expression is mediated by one of the two receptor binding sites. In the close vicinity of elements I and II, we detected two binding sites of secretion enhancer binding protein 3 (SEBP 3). Like receptor element I, one of these sites also proved to be necessary, but not sufficient, for expression of Sgs-4. Therefore, induction of Sgs-4 requires binding of both ecdysone receptor and SEBP 3 to a complex hormone response unit, which also contains binding sites for a third factor, SEBP 2. The SEBP 2 sites coincide with binding sites of products of the Broad-Complex locus, which has been implicated recently with transduction of the hormonal signal. Thus, the available data suggest that induction of Sgs-4, and possibly other 'intermolt genes', is a combination of a primary and a secondary response to the hormone.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Fatores de Transcrição
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Proteínas do Grude Salivar de Drosophila
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Receptores de Esteroides
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Regulação da Expressão Gênica no Desenvolvimento
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Proteínas de Ligação a DNA
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Drosophila melanogaster
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Ecdisona
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Proteínas de Choque Térmico
Limite:
Animals
Idioma:
En
Ano de publicação:
1995
Tipo de documento:
Article