The translation inhibitor anisomycin induces Elk-1-mediated transcriptional activation of egr-1 through multiple mitogen-activated protein kinase pathways
Experimental & Molecular Medicine
; : 677-685, 2006.
Article
em En
| WPRIM
| ID: wpr-106417
Biblioteca responsável:
WPRO
ABSTRACT
The early growth response-1 gene (egr-1) encodes a zinc-finger transcription factor Egr-1 and is rapidly inducible by a variety of extracellular stimuli. Anisomycin (ANX), a protein synthesis inhibitor, stimulates mitogen-activated protein kinase (MAPK) pathways and thereby causes a rapid induction of immediate-early response genes. We found that anisomycin treatment of U87MG glioma cells resulted in a marked, time-dependent increase in levels of Egr-1 protein. The results of Northern blot analysis and reporter gene assay of egr-1 gene promoter (Pegr-1) activity indicate that the ANX- induced increase in Egr-1 occurs at the transcriptional level. Deletion of the serum response element (SRE) in the 5'-flanking region of egr-1 gene abolished ANX-induced Pegr-1 activity. ANX induced the phosphorylation of the ERK1/2, JNK, and p38 MAPKs in a time-dependent manner and also induced transactivation of Gal4-Elk-1, suggesting that Elk-1 is involved in SRE-mediated egr-1 transcription. Transient transfection of dominant-negative constructs of MAPK pathways blocked ANX-induced Pegr-1 activity. Furthermore, pretreatment with specific MAPK pathway inhibitors, including the MEK inhibitor U0126, the JNK inhibitor SP600125, and the p38 kinase inhibitor SB202190, completely inhibited ANX-inducible expression of Egr-1. Taken together, these results suggest that all three MAPK pathways play a crucial role in ANX-induced transcriptional activation of Pegr-1 through SRE-mediated transactivation of Elk
Palavras-chave
Texto completo:
1
Índice:
WPRIM
Assunto principal:
Biossíntese de Proteínas
/
Ativação Transcricional
/
Regiões Promotoras Genéticas
/
Sistema de Sinalização das MAP Quinases
/
Elemento de Resposta Sérica
/
Linhagem Celular Tumoral
/
MAP Quinases Reguladas por Sinal Extracelular
/
Proteínas Quinases JNK Ativadas por Mitógeno
/
Proteínas Quinases p38 Ativadas por Mitógeno
/
Inibidores de Proteínas Quinases
Limite:
Humans
Idioma:
En
Revista:
Experimental & Molecular Medicine
Ano de publicação:
2006
Tipo de documento:
Article