TBP : TATA-box binding protein

Description

The TBP (TATA-box binding protein) is a protein-coding gene located on chromosome 6.

The TBP gene provides instructions for making a protein called the TATA-box binding protein. This protein is active in cells and tissues throughout the body, where it plays an essential role in regulating the activity of most genes. The TATA-box binding protein attaches (binds) to a particular sequence of DNA known as the TATA box. This sequence occurs in a regulatory region of DNA near the beginning of many genes. Once the protein is attached to the TATA box near a gene, it acts as a landmark to indicate where other enzymes should start reading the gene. The process of reading a gene's DNA and transferring the information to a similar molecule called messenger RNA (mRNA) is known as transcription. One region of the TBP gene contains a particular DNA segment known as a CAG/CAA trinucleotide repeat. This segment is made up of a series of three DNA building blocks (nucleotides) that appear multiple times in a row. Normally, the CAG/CAA segment is repeated 25 to 40 times within the gene.

The TFIID complex is a key player in the initiation of RNA polymerase II (Pol II)-dependent transcription. It binds to promoters, both those with and without a TATA box, through its subunit TBP (TATA-box-binding protein). TFIID then assembles the pre-initiation complex (PIC), which is essential for transcription to start. TFIID is composed of TBP and a set of TBP-associated factors (TAFs). It's structured into three modules: TFIID-A, TFIID-B, and TFIID-C, with TBP forming the TFIID-A module alongside TAF3 and TAF5. As part of TFIID, TBP bends the promoter DNA, which is crucial for the proper assembly of the PIC. TBP is also involved in RNA polymerase III-mediated transcription as part of a BRF2-containing complex. Additionally, TBP plays a role in RNA polymerase I-dependent transcription as part of the SL1/TIF-IB complex, which helps assemble the PIC during this process. The SL1 complex is also involved in stabilizing the nucleolar transcription factor 1 (UBTF) on rDNA.

TBP is also known as GTF2D, GTF2D1, HDL4, SCA17, TBP1, TFIID.

Associated Diseases

• Spinocerebellar ataxia type 17
• Spinocerebellar ataxia 17
• Parkinson disease, late-onset
• Huntington's disease-like