Evolutionary conservation of an atypical glucocorticoid-responsive element in the human tyrosine hydroxylase gene.
J Neurochem
; 126(1): 19-28, 2013 Jul.
Article
em En
| MEDLINE
| ID: mdl-23647419
ABSTRACT
The human tyrosine hydroxylase (hTH) gene has a 42 bp evolutionarily conserved region designated (CR) II at -7.24 kb, which bears 93% homology to the region we earlier identified as containing the glucocorticoid response element, a 7 bp activator protein-1 (AP-1)-like motif in the rat TH gene. We cloned this hTH-CRII region upstream of minimal basal hTH promoter in luciferase (Luc) reporter vector, and tested glucocorticoid responsiveness in human cell lines. Dexamethasone (Dex) stimulated Luc activity of hTH-CRII in HeLa cells, while mifepristone, a glucocorticoid receptor (GR) antagonist, prevented Dex stimulation. Deletion of the 7 bp 5'-TGACTAA at -7243 bp completely abolished the Dex-stimulated Luc activity of hTH-CRII construct. The AP-1 agonist, tetradeconoyl-12,13-phorbol acetate (TPA), also stimulated hTH promoter activity, and Dex and TPA together further accentuated this response. Chromatin immunoprecipitation assays revealed the presence of both GR and AP-1 proteins, especially Jun family members, at this hTH promoter site. Dex did not stimulate hTH promoter activity in a catecholaminergic cell line, which had low endogenous GR levels, but did activate the response when GR was expressed exogenously. Thus, our studies have clearly identified a glucocorticoid-responsive element in a 7 bp AP-1-like motif in the promoter region at -7.24 kb of the human TH gene.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Tirosina 3-Mono-Oxigenase
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Sequência Conservada
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Elementos de Resposta
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Glucocorticoides
Limite:
Humans
Idioma:
En
Revista:
J Neurochem
Ano de publicação:
2013
Tipo de documento:
Article
País de afiliação:
Estados Unidos