Initiation of transcription by RNA polymerase II requires the activities of more than 70 polypeptides. The protein that coordinates these activities is transcription factor IID (TFIID), which binds to the core promoter to position the polymerase properly, serves as the scaffold for assembly of the remainder of the transcription complex, and acts as a channel for regulatory signals. TFIID is composed of the TATA-binding protein (TBP) and a group of evolutionarily conserved proteins known as TBP-associated factors or TAFs. TAFs may participate in basal transcription, serve as coactivators, function in promoter recognition or modify general transcription factors (GTFs) to facilitate complex assembly and transcription initiation. This gene encodes one of the larger subunits of TFIID that has been shown to potentiate transcriptional activation by retinoic acid, thyroid hormone and vitamin D3 receptors. In addition, this subunit interacts with the transcription factor CREB, which has a glutamine-rich activation domain, and binds to other proteins containing glutamine-rich regions. Aberrant binding to this subunit by proteins with expanded polyglutamine regions has been suggested as one of the pathogenetic mechanisms underlying a group of neurodegenerative disorders referred to as polyglutamine diseases.[3]
Yeast TFIID comprises the TATA bindingprotein and 14 TBP-associated factors (TAFIIs), nine of which contain histone-fold domains (INTERPRO). The C-terminal region of the TFIID-specific yeast TAF4 (yTAF4) containing the HFD shares strong sequence similarity with Drosophila (d)TAF4 and human TAF4. A structure/function analysis of yTAF4 demonstrates that the HFD, a short conserved C-terminal domain (CCTD), and the region separating them are all required for yTAF4 function. This region of similarity is found in Transcriptioninitiation factor TFIID component TAF4.[8]
↑Mengus G, May M, Carré L, Chambon P, Davidson I (July 1997). "Human TAF(II)135 potentiates transcriptional activation by the AF-2s of the retinoic acid, vitamin D3, and thyroid hormone receptors in mammalian cells". Genes Dev. 11 (11): 1381–95. doi:10.1101/gad.11.11.1381. PMID9192867.
↑Pointud JC, Mengus G, Brancorsini S, Monaco L, Parvinen M, Sassone-Corsi P, Davidson I (May 2003). "The intracellular localisation of TAF7L, a paralogue of transcription factor TFIID subunit TAF7, is developmentally regulated during male germ-cell differentiation". J. Cell Sci. 116 (Pt 9): 1847–58. doi:10.1242/jcs.00391. PMID12665565.
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Kashanchi F, Piras G, Radonovich MF, Duvall JF, Fattaey A, Chiang CM, Roeder RG, Brady JN (1994). "Direct interaction of human TFIID with the HIV-1 transactivator tat". Nature. 367 (6460): 295–9. doi:10.1038/367295a0. PMID8121496.
Wang Z, Morris GF, Rice AP, Xiong W, Morris CB (1996). "Wild-type and transactivation-defective mutants of human immunodeficiency virus type 1 Tat protein bind human TATA-binding protein in vitro". J. Acquir. Immune Defic. Syndr. Hum. Retrovirol. 12 (2): 128–38. doi:10.1097/00042560-199606010-00005. PMID8680883.
Zhou Q, Sharp PA (1996). "Tat-SF1: cofactor for stimulation of transcriptional elongation by HIV-1 Tat". Science. 274 (5287): 605–10. doi:10.1126/science.274.5287.605. PMID8849451.
García-Martínez LF, Ivanov D, Gaynor RB (1997). "Association of Tat with purified HIV-1 and HIV-2 transcription preinitiation complexes". J. Biol. Chem. 272 (11): 6951–8. doi:10.1074/jbc.272.11.6951. PMID9054383.
Brand M, Yamamoto K, Staub A, Tora L (1999). "Identification of TATA-binding protein-free TAFII-containing complex subunits suggests a role in nucleosome acetylation and signal transduction". J. Biol. Chem. 274 (26): 18285–9. doi:10.1074/jbc.274.26.18285. PMID10373431.
Inada A, Someya Y, Yamada Y, Ihara Y, Kubota A, Ban N, Watanabe R, Tsuda K, Seino Y (1999). "The cyclic AMP response element modulator family regulates the insulin gene transcription by interacting with transcription factor IID". J. Biol. Chem. 274 (30): 21095–103. doi:10.1074/jbc.274.30.21095. PMID10409662.
