TATA box
The TATA-box is the site of preinitiation complex formation, which is the first step in transcription initiation in eukaryotes. Formation of the preinitiation complex begins when the multi-subunit transcription factor II D (TFIID) binds to the TATA box at its TATA-binding protein (TBP) subunit. TBP binds to the minor groove of the TATA box via a region of antiparallel β sheets in the protein. Three types of molecular interactions contribute to TBP binding to the TATA box: