The TATA-binding protein (also called the TATA-box-binding protein/TBP) is the key initial event in the recognition of a TATA box promoter region in DNA by RNA polymerase II in eukaryotic transcription, and the activation of an active transcription complex. The TBP is a component of the TFIID complex, a transcription factor essential for initiating transcription by RNA polymerase II. TBP is a saddle-shaped protein consisting of two subunits; the concave subunit binds to the TATA-box sequence of DNA and this induces conformational change of the binding protein. The minor groove of the DNA is unwound and widened, enabling more extensive contact with the TBP, using hydrophobic interactions.
The surface of the TBP saddle provides docking sites for binding of other components, allowing other transcription factors to assemble in a defined sequence and for transcription.
- ↑ Biochemistry eighth edition, JM Berg, JL Tymoczko, GJ Gatto Jr., L Stryer, W.H. Freeman and Company, New York, 2015