Crystal structure of negative cofactor 2 recognizing the TBP-DNA transcription complex.
The X-ray structure of a ternary complex of Negative Cofactor 2 (NC2), the TATA box binding protein (TBP), and DNA has been determined at 2.6 A resolution. The N termini of NC2 alpha and beta resemble histones H2A and H2B, respectively, and form a heterodimer that binds to the bent DNA double helix on the underside of the preformed TBP-DNA complex via electrostatic interactions. NC2beta contributes to inhibition of TATA-dependent transcription through interactions of its C-terminal alpha helix with a conserved hydrophobic feature on the upper surface of TBP, which in turn positions the penultimate alpha helix of NC2beta to block recognition of the TBP-DNA complex by transcription factor IIB. Further regulatory implications of the NC2 heterodimer structure are discussed.
Pubmed ID: 11461703 RIS Download
Amino Acid Sequence | Animals | Caenorhabditis elegans | Crystallography, X-Ray | DNA | DNA-Binding Proteins | Drosophila melanogaster | Histones | Humans | Models, Molecular | Molecular Sequence Data | Nucleic Acid Conformation | Phosphoproteins | Protein Structure, Secondary | Sequence Alignment | Sequence Homology, Amino Acid | Static Electricity | TATA Box | TATA-Box Binding Protein | Transcription Factor TFIIA | Transcription Factor TFIIB | Transcription Factors | Transcription, Genetic | Xenopus laevis