Co-crystal structure of TBP recognizing the minor groove of a TATA element

The three-dimensional structure of a TATA-box binding polypeptide complexed with the TATA element of the adenovirus major late promoter has been determined by X-ray crystallography at 2.25 A resolution. Binding of the saddle-shaped protein induces a conformational change in the DNA, inducing sharp kinks at either end of the sequence TATAAAAG. Between the kinks, the right-handed double helix is smoothly curved and partially unwound, presenting a widened minor groove to TBP's concave, antiparallel beta-sheet. Side-chain/base interactions are restricted to the minor groove, and include hydrogen bonds, van der Waals contacts and phenylalanine-base stacking interactions.