TBP Antibody

Initiation of transcription by RNA polymerase II requires the activities of more than 70 polypeptides. The protein that coordinates these activities is transcription factor IID (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 TBP, the TATA-binding protein. A distinctive feature of TBP is a long string of glutamines in the N-terminus. This region of the protein modulates the DNA binding activity of the C terminus, and modulation of DNA binding affects the rate of transcription complex formation and initiation of transcription. The number of CAG repeats encoding the polyglutamine tract is usually 32-39, and expansion of the number of repeats increases the length of the polyglutamine string and is associated with spinocerebellar ataxia 17, a neurodegenerative disorder classified as a polyglutamine disease. Two transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Feb 2010]

TBP: General transcription factor that functions at the core of the DNA-binding multiprotein factor TFIID. Binding of TFIID to the TATA box is the initial transcriptional step of the pre- initiation complex (PIC), playing a role in the activation of eukaryotic genes transcribed by RNA polymerase II. Component of the transcription factor SL1/TIF-IB complex, which is involved in the assembly of the PIC (preinitiation complex) during RNA polymerase I-dependent transcription. The rate of PIC formation probably is primarily dependent on the rate of association of SL1 with the rDNA promoter. SL1 is involved in stabilization of nucleolar transcription factor 1/UBTF on rDNA. Binds DNA as monomer. Belongs to the TFIID complex together with the TBP-associated factors (TAFs). Component of the transcription factor SL1/TIF-IB complex, composed of TBP and at least TAF1A, TAF1B TAF1C and TAF1D. Association of TBP to form either TFIID or SL1/TIF-IB appears to be mutually exclusive. Interacts with TAF1A, TAF1B and TAF1C. Interacts with TFIIB, NCOA6, DRAP1, DR1 and ELF3. Interacts with SPIB, SNAPC1, SNAPC2 and SNAPC4. Interacts with UTF1. Interacts with BRF2. Interacts with UBTF. Interacts with GPBP1. Interacts with CITED2. Interacts with ATF7IP. Interacts with HIV-1 Tat. Widely expressed, with levels highest in the testis and ovary. Belongs to the TBP family.

Protein type: Transcription initiation complex; DNA-binding; Nuclear receptor co-regulator

Chromosomal Location of Human Ortholog: 6q27

Cellular Component: nucleoplasm; transcription factor TFIID complex; male pronucleus; cytoplasm; female pronucleus; transcription factor TFIIA complex

Molecular Function: protein binding; transcription factor binding; transcription factor activity

Biological Process: chromatin silencing at rDNA; transcription from RNA polymerase II promoter; transcription initiation from RNA polymerase II promoter; viral reproduction; positive regulation of transcription, DNA-dependent; RNA elongation from RNA polymerase I promoter; transcription from RNA polymerase I promoter; termination of RNA polymerase I transcription; regulation of gene expression, epigenetic; transcription from RNA polymerase III promoter; negative regulation of gene expression, epigenetic; RNA elongation from RNA polymerase II promoter; gene expression; spermatogenesis; transcription initiation from RNA polymerase I promoter

Disease: Parkinson Disease, Late-onset; Spinocerebellar Ataxia 17