TAF1 (D6J8B) Rabbit mAb #12781

TATA-binding protein (TBP) is a ubiquitously expressed nuclear protein that functions at the core of the general transcription factor protein complex TFIID (1-3). TFIID, which contains TBP and 13 TBP-associated factors (TAFs), contributes to the formation of the transcription pre-initiation complex, an assembly of multiple protein complexes (TFIIA, TFIIB, TFIIE, TFIIF, TFIIH, and RNA polymerase II) that bind to a gene promoter during the initiation of transcription (1-3). Once the pre-initiation complex is formed, RNA polymerase II becomes competent for elongation and transcribes the body of a gene. TBP functions in the recruitment of TFIID by binding to the TATA-box sequence found approximately 25 base pairs upstream of the transcription start site of many protein-coding genes. In addition, many transcriptional activator proteins interact with TBP and various TAF proteins to facilitate recruitment of TFIID and formation of the pre-initiation complex.
TBP-associated factor 1 (TAF1) is the largest subunit of TFIID and possesses multiple enzymatic activities including a protein kinase activity (4), a histone acetyltransferase activity (5), and both E1 and E2 ubiquitin-activating and conjugating activities (6,7). The target proteins of these enzymatic activities include both histones and non-histones and play a critical role in regulating transcription activation (3). In addition, TAF1 contains two tandem bromodomains that recognize acetylated histone H3 and histone H4 and are thought to promote the recruitment and association of TFIID at target promoters post activator recruitment of coactivators for gene expression (8,9).