The enhanceosome.
The interferon-beta (IFN-beta) enhanceosome is a paradigm for understanding the role of transcription factor complexes in eukaryotic signal integration. Recent structural studies provide a complete atomic model of the enhanceosome at the protein-DNA interface. The composite model shows how binding of eight transcription factors to enhancer DNA creates a continuous recognition surface. The extensive overlap of individual binding sites creates a composite element that ensures that the enhancer operates as a single unit of regulation. The absence of major protein-protein interfaces between the transcription factors suggests that cooperative binding occurs through a combination of binding-induced conformational changes in DNA structure and specific interactions with coactivator proteins such as CBP/p300. Contacts with virtually every nucleotide explain why the enhancer is evolutionary conserved in mammalian genomes.
Panne
Daniel
D
EMBL, 6 Rue Jules Horowitz, BP181, 38042 Grenoble, France. panne@embl.fr
D000818:Animals; D001483:Base Sequence; D004742:Enhancer Elements, Genetic / Q000235:genetics*; D016899:Interferon-beta / Q000235:genetics*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D014157:Transcription Factors / Q000737:chemistry* / Q000378:metabolism*
D014157:Transcription Factors; D016899:Interferon-beta