Egr-1 is necessary for fibroblast growth factor-2-induced transcriptional activation of the glial cell line-derived neurotrophic factor in murine astrocytes.
J Biol Chem
; 284(44): 30583-93, 2009 Oct 30.
Article
em En
| MEDLINE
| ID: mdl-19721135
ABSTRACT
Glial cell line-derived neurotrophic factor (Gdnf) promotes neurite outgrowth and survival of neuronal cells, but its transcriptional regulation is poorly understood. Here, we sought to investigate the mechanism underlying fibroblast growth factor-2 (FGF2) induction of Gdnf expression in astrocytes. We found that FGF2 stimulation of rat astrocytes induced expression of Egr-1 at a high level. Sequence analysis of the rat Gdnf gene identified three overlapping Egr-1-binding sites between positions -185 and -163 of the rat Gdnf promoter. Transfection studies using a series of deleted Gdnf promoters revealed that these Egr-1-binding sites are required for maximal activation of the Gdnf promoter by FGF2. Chromatin immunoprecipitation analysis indicated that Egr-1 binds to the Gdnf promoter. Furthermore, the induction of Gdnf expression by FGF2 is strongly attenuated both in C6 glioma cells stably expressing Egr-1-specific small interfering RNA and in primary cultured astrocytes from the Egr-1 knock-out mouse. Additionally, we found that stimulation of the ERK and JNK pathways by FGF2 is functionally linked to Gdnf expression through the induction of Egr-1. These data demonstrate that FGF2-induced Gdnf expression is mediated by the induction of Egr-1 through activation of the ERK and JNK/Elk-1 signaling pathways.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Ativação Transcricional
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Astrócitos
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Fator 2 de Crescimento de Fibroblastos
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Proteína 1 de Resposta de Crescimento Precoce
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Fator Neurotrófico Derivado de Linhagem de Célula Glial
Tipo de estudo:
Prognostic_studies
Limite:
Animals
Idioma:
En
Revista:
J Biol Chem
Ano de publicação:
2009
Tipo de documento:
Article