transcription initiation factor TFIID subunit 1; cell cycle gene 1 protein; TBP-associated factor 250 kD; p250; transcription initiation factor TFIID 250 kD subunit; TAF(II)250; TAFII-250; TAFII250 (TAF1, BA2R, CCG,1 CCGS, TAF2A)

Function

• largest component & core scaffold of the TFIID basal transcription factor complex
• binds all other subunits of TFIID
• role in progression through the late G1 phase of the cell cycle
• contains novel N- & C-terminal Ser/Thr kinase domains which can autophosphorylate or transphosphorylate other transcription factors
• phosphorylates TP53 on Thr-55 destabilizing p53 leading to MDM2-mediated degradation of TP53 & inducing G1 progression
• essential for progression of the G1 phase of the cell cycle
• phosphorylates GTF2A1 & GTF2F1 on Ser
• possesses DNA- binding activity
• TAF1, when part of the TFIID complex, interacts with C-terminus of TP53
• RB1 interacts with the N-terminal domain of TAF1
• inhibited by RB1
• interacts with ASF1A & ASF1B
• autophosphorylates on Ser
• phosphorylated by casein kinase 2 in vitro

Cofactor: Mg+2

Structure

• belongs to the TAF1 family
• contains 2 bromo domains
• contains 1 HMG box DNA-binding domain
• contains 2 protein kinase domains

Compartment

nucleus

Alternative splicing

named isoforms=4

Pathology

• defects in TAF1 are associated with X-linked torsion dystonia type 3

More general terms

• transcription factor IID subunit
• DNA-binding protein
• serine/threonine kinase

Database

• Entrez gene: http://www.ncbi.nlm.nih.gov/sites/entrez?db=gene&cmd=Retrieve&dopt=Graphics&list_uids=6872
• Kegg: http://www.genome.jp/dbget-bin/www_bget?hsa:6872
• OMIM: https://mirror.omim.org/entry/313650
• OMIM: https://mirror.omim.org/entry/314250
• UniProt: http://www.uniprot.org/uniprot/P21675.html