with different transcription factors, TBP can initiate transcription from different RNA polymerases. There are several related TBPs, including TBP-like (TBPL) proteins. Structure The C-terminal core of TBP (~180 residues) is highly conserved and contains two 88-amino acid repeats that produce a saddle-shaped structure that straddles the DNA; this region binds to the TATA box and interacts with transcription factors and regulatory proteins . By contrast, the N-terminal region varies in both length and sequence. References External links GeneReviews/NCBI/NIH/UW entry on Spinocerebellar Ataxia Type 17 Interactive TBP Structure at massey.ac.nz Proteins Genes Transcription factors