TAF1 Antibody – Rabbit

Initiation of transcription by RNA polymerase II requires the activities of more than 70 polypeptides. The protein that coordinates these activities is the basal transcription factor TFIID, which binds to the core promoter to position the polymerase properly, serves as the scaffold for assembly of the remainder of the transcription complex, and acts as a channel for regulatory signals. TFIID is composed of the TATA-binding protein (TBP) and a group of evolutionarily conserved proteins known as TBP-associated factors or TAFs. TAFs may participate in basal transcription, serve as coactivators, function in promoter recognition or modify general transcription factors (GTFs) to facilitate complex assembly and transcription initiation. This gene encodes the largest subunit of TFIID. This subunit binds to core promoter sequences encompassing the transcription start site. It also binds to activators and other transcriptional regulators, and these interactions affect the rate of transcription initiation. This subunit contains two independent protein kinase domains at the N and C-terminals, but also possesses acetyltransferase activity and can act as a ubiquitin-activating/conjugating enzyme. This gene is part of a complex transcriptional unit (TAF1/DYT3), wherein some products share exons with TAF1 as well as additional exons downstream.[provided by RefSeq, Aug 2009]

TAF1: Largest component and core scaffold of the TFIID basal transcription factor complex. Contains novel N- and C-terminal Ser/Thr kinase domains which can autophosphorylate or transphosphorylate other transcription factors. Phosphorylates TP53 on 'Thr-55' which leads to MDM2-mediated degradation of TP53. Phosphorylates GTF2A1 and GTF2F1 on Ser residues. Possesses DNA- binding activity. Essential for progression of the G1 phase of the cell cycle. Defects in TAF1 are the cause of dystonia type 3 (DYT3); also called X-linked dystonia-parkinsonism (XDP). DYT3 is a X-linked dystonia-parkinsonism disorder. Dystonia is defined by the presence of sustained involuntary muscle contractions, often leading to abnormal postures. DYT3 is characterized by severe progressive torsion dystonia followed by parkinsonism. Its prevalence is high in the Philippines. DYT3 has a well-defined pathology of extensive neuronal loss and mosaic gliosis in the striatum (caudate nucleus and putamen) which appears to resemble that in Huntington disease. Belongs to the TAF1 family. 4 isoforms of the human protein are produced by alternative splicing.

Protein type: EC 2.3.1.48; DNA-binding; Protein kinase, Ser/Thr (non-receptor); EC 2.7.11.1; Kinase, protein; Protein kinase, atypical; Transcription, coactivator/corepressor; ATYPICAL group; TAF1 family

Chromosomal Location of Human Ortholog: Xq13.1

Cellular Component: nucleoplasm; transcription factor TFIID complex

Molecular Function: protein serine/threonine kinase activity; protein binding; histone acetyltransferase activity; p53 binding; sequence-specific DNA binding; TATA-binding protein binding; transcription coactivator activity; transcription factor binding; ATP binding

Biological Process: transcription from RNA polymerase II promoter; transcription initiation from RNA polymerase II promoter; viral reproduction; protein amino acid autophosphorylation; transcription initiation; peptidyl-threonine phosphorylation; transcriptional preinitiation complex assembly; cell cycle; peptidyl-serine phosphorylation; positive regulation of proteasomal ubiquitin-dependent protein catabolic process; RNA elongation from RNA polymerase II promoter; positive regulation of transcription from RNA polymerase II promoter; gene expression; histone acetylation; response to DNA damage stimulus

Disease: Dystonia 3, Torsion, X-linked