TFIID

TFIID is a multi-subunit complex that plays a pivotal role in the initiation of transcription by RNA polymerase II. It is one of several general transcription factors that make up the RNA polymerase II holoenzyme.

Structure

TFIID is composed of the TATA-binding protein (TBP) and 13 TBP-associated factors (TAFs). The TBP subunit of TFIID recognizes and binds to the TATA box promoter sequence in the DNA. The TAFs, on the other hand, serve to regulate the activity of TFIID in a promoter context-dependent manner.

Function

The primary function of TFIID is to accurately position RNA polymerase II at gene promoters and initiate transcription. It does this by binding to the TATA box sequence in the promoter region of the gene. Once bound, TFIID recruits other transcription factors and RNA polymerase II to form the pre-initiation complex.

Role in Disease

Mutations in the genes encoding TFIID subunits have been associated with several human diseases. For example, mutations in the TBP gene have been linked to spinocerebellar ataxia and Huntington's disease. Additionally, some forms of cancer have been associated with alterations in TFIID function.

See Also

• Transcription (genetics)
• RNA polymerase II
• TATA box
• TATA-binding protein
• Transcription factor