Two distinct NF-kappa B complexes differing in their larger subunit bind the E-selectin promoter kappa B element.
AUTOR(ES)
Hooft van Huijsduijnen, R
RESUMO
We have investigated the proteins binding the E-selectin promoter NF-kappa B element in its natural DNA context, using probes extending beyond the NF-kappa B recognition decamer. In band shift assays, we detected two distinct NF-kappa B complexes using nuclear extracts from several cytokine-induced cells. Subunit-specific antisera as blockers of complex formation plus DNA-protein cross-linking experiments revealed the faster migrating form to contain the NF-kappa B p50 plus p65 subunits. In contrast, the slower migrating form is composed of p50 plus the p65-related p75 protein. We show as the crucial determinant in generation of the larger complex the presence of more than five basepairs extra DNA sequence downstream of the NF-kappa B-site. Although no specific sequence is required in this 3' extended DNA to bind the larger complex, an intact kappa B binding site is. This may be explained by a requirement for activated p50 as part of this complex. The potential for a regulatory role for the p75 containing complex on the E-selectin promoter is discussed.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=309871Documentos Relacionados
- Cooperativity between two NF-kappa B complexes, mediated by high-mobility-group protein I(Y), is essential for cytokine-induced expression of the E-selectin promoter.
- Cyclic AMP-independent ATF family members interact with NF-kappa B and function in the activation of the E-selectin promoter in response to cytokines.
- Three NF-kappa B binding sites in the human E-selectin gene required for maximal tumor necrosis factor alpha-induced expression.
- NF-kappa B subunit-specific regulation of the interleukin-8 promoter.
- NF-kappa B activates the HIV promoter in neurons.