Concerted participation of NF-kappa B and C/EBP heteromer in lipopolysaccharide induction of serum amyloid A gene expression in liver.
J Biol Chem
; 270(13): 7365-74, 1995 Mar 31.
Article
de En
| MEDLINE
| ID: mdl-7706280
ABSTRACT
The promoter region of the rabbit serum amyloid A (SAA) gene contains two adjacent C/EBP and one NF-kappa B binding element. Involvement of these elements in SAA gene induction, following lipopolysaccharide (LPS) stimulation of the liver, has been studied by investigating LPS-activated transcription factors and their interaction with the promoter elements of the SAA gene. Appearance of complexes in the electrophoretic mobility shift assay has indicated that DNA-binding proteins that interact with the NF-kappa B element of the SAA promoter are induced in the LPS-treated rabbit liver. Presence of RelA (p65 subunit of NF-kappa B) in these complexes was demonstrated by the ability of RelA-specific antisera to supershift the DNA-protein complexes. LPS also induced several members of the C/EBP family of transcription factors, which interacted with the C/EBP motifs of the SAA promoter. Activated C/EBP and RelA form a RelA-C/EBP heteromeric complex that associates with varying affinity to NF-kappa B and C/EBP elements of the SAA gene. Transfection assays using both transcription factor genes have demonstrated that the heteromeric complex of NF-kappa B and C/EBP is a much more potent transactivator of SAA expression than each transcription factor alone. The heteromeric complex efficiently promotes transcription from both NF-kappa B and C/EBP sites.
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Collection:
01-internacional
Base de données:
MEDLINE
Sujet principal:
Facteurs de transcription
/
Protéine amyloïde A sérique
/
Protéines nucléaires
/
Expression des gènes
/
Lipopolysaccharides
/
Facteur de transcription NF-kappa B
/
Régions promotrices (génétique)
/
Protéines de liaison à l'ADN
/
Foie
Limites:
Animals
Langue:
En
Journal:
J Biol Chem
Année:
1995
Type de document:
Article
Pays d'affiliation:
États-Unis d'Amérique