ABSTRACT
The structure and behavior of full-length human TBP binding the adenovirus major late promoter (AdMLP) have been characterized using biophysical methods. The human protein induces a 97 degrees bend in DNA AdMLP. The high-resolution functional data provide a quantitative energetic and kinetic description of the partial reaction sequence as native human TBP binds rapidly to a consensus promoter with high affinity. The reaction proceeds with successive formation of three bound species, all having strongly bent DNA, with the concurrence of binding and bending demonstrated by both fluorescence and anisotropy stopped flow. These results establish the protein species dependence of the TBP-DNA AdMLP structure and recognition mechanism. Additionally, the strong correlation between the DNA bend angle and transcription efficiency demonstrated previously for yeast TBP is shown to extend to human TBP. The heterologous NH 2-terminal domains are the apparent source of the species-specific differences. Together with previous studies the present work establishes that TBP wt-DNA TATA function and structure depend both on the TATA box sequence and on the TBP species.
