| Description: |
Transcription initiation factor TFIID subunit 12 (TAF12) is a component of the DNA-binding general transcription factor complex TFIID []and the transcription regulatory histone acetylation (HAT) complexes SAGA [], SALSA []and SLIK [].The DNA-binding general transcription factor complex TFIID is central to the initiation of DNA-dependent RNA polymerase II transcription. TFIID is the only general transcription initiation factor that bind to the TATA box. The binding of TFIID to the TATA-box is the first step in the formation of a complex able to initiate transcription []. TFIID consists of the TATA binding protein (TBP) and 14 TBP-associated factors (TAFs). One copy of each TAF1, TAF2, TAF3, TAF7, TAF8, TAF11, TAF13, two copies of each TAF4, TAF5, TAF6, TAF9, TAF10, TAF12, and three copies of TAF14 [].The transcription regulatory histone acetylation complex Spt-Ada-Gcn5 acetyltransferase (SAGA) is involved in RNA polymerase II-dependent transcriptional regulation of approximately 10% of yeast genes. SAGA preferentially acetylates histones H3 and H2B and deubiquitinates histone H2B []. SAGA is known as PCAF in vertebrates and PCAF acetylates nucleosomal histone H3 []. The SAGA complex consists of at least TRA1, CHD1, SPT7, TAF5, ADA3, SGF73, SPT20/ADA5, SPT8, TAF12, TAF6, HFI1/ADA1, UBP8, GCN5, ADA2, SPT3, SGF29, TAF10, TAF9, SGF11 and SUS1, and some of these components are present as two copies. The complex is built up from distinct modules, each of which has a separate function and crosslinks with either other proteins or other modules in the complex [].SLIK (SAGA-like) is a multi-subunit histone acetyltransferase complex that preferentially acetylates histones H3 and H2B and deubiquitinates histone H2B. It is an embellishment of the SAGA complex. The yeast SLIK complex consists of at least TRA1, CHD1, SPT7, CC TAF5, ADA3, SPT20, RTG2, TAF12, TAF6, HFI1, UBP8 (a deubiquitinase), GCN5, ADA2, SPT3, SGF29, TAF10 and TAF9 [, ].The yeast SALSA complex is an altered form of the SAGA complex and consists of at least TRA1, SPT7 (C-terminal truncated form), TAF5, ADA3, SPT20, TAF12, TAF6, HFI1, GCN5, ADA2 and SPT3 []. |
