cl18963

TATA Binding Protein (TBP) Associated Factor 6 (TAF6) 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 6 (TAF6) is one of several TAFs that bind TBP and are involved in forming Transcription Factor IID (TFIID) complex. TFIID is one of seven General Transcription Factors (GTFs) (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 pre-initiation 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. These TAFs, with the help of specific activators, are required only for expression of a subset of genes and are not universally involved for transcription as are GTFs. 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. The minimal HFD contains three alpha-helices linked by two loops and is found in core histones, TAFs and many other transcription factors. TFIID has a histone octamer-like substructure. TAF6 is a shared subunit of histone acetyltransferase complex SAGA and TFIID complexes. TAF6 domain interacts with TAF9 and makes a novel histone-like heterodimer that is structurally related to histones H4 and H3. TAF6 may also interact with the downstream core promoter element (DPE).