TATA Binding Protein (TBP) Associated Factor 7 (TAF7) is one of several TAFs that bind TBP and is involved in forming Transcription Factor IID (TFIID) complex
The TATA Binding Protein (TBP) Associated Factor 7 (TAF7) is one of several TAFs that bind TBP and are involved in forming the Transcription Factor IID (TFIID) complex. TFIID is one of seven General Transcription Factors (GTF) (TFIIA, TFIIB, TFIID, TFIIE, TFIIF, and TFIID) that are involved in accurate initiation of transcription by RNA polymerase II in eukaryotes. TFIID plays an important role in the recognition of promoter DNA and assembly of the preinitiation complex. TFIID complex is composed of the TBP and at least 13 TAFs. TAFs are named after their electrophoretic mobility in polyacrylamide gels in different species. A new, unified nomenclature has been suggested for the pol II TAFs to show the relationship between TAF orthologs and paralogs. Several hypotheses are proposed for TAFs functions such as serving as activator-binding sites, core-promoter recognition or a role in essential catalytic activity. Each TAF, with the help of a specific activator, is required only for expression of subset of genes and is not universally involved for transcription as are GTFs. TAF7 is involved in the regulation of the transition from PIC assembly to initiation and elongation. In yeast and human cells, TAFs have been found as components of other complexes besides TFIID. Several TAFs interact via histone-fold (HFD) motifs; the HFD is the interaction motif involved in heterodimerization of the core histones and their assembly into nucleosome octamers.