Ma D, Watanabe H, Mermelstein F, Admon A, Oguri K, Sun X, Wada T, Imai T, Shiroya T, Reinberg D
Department of Biochemistry, Robert Wood Johnson Medical School, University of Medicine and Dentistry of New Jersey, Piscataway 08854-5635.
Genes Dev. 1993 Nov;7(11):2246-57. doi: 10.1101/gad.7.11.2246.
Transcription factor IIA has been shown to interact with the TATA-binding protein and to act early during preinitiation complex formation. The human factor is composed of three subunits (alpha, beta, gamma). A human cDNA clone encoding the largest subunit of TFIIA (alpha) was isolated. The recombinant alpha polypeptide, together with the beta and gamma subunits, was capable of reconstituting TFIIA activity. Studies using antibodies raised against recombinant alpha polypeptide demonstrate that TFIIA can be an integral component of the preinitiation complex. We demonstrate that TFIIA not only interacts with TBP but also can associate with the TFIID complex. Functional assays establish that TFIIA has no apparent role in basal transcription but plays an important role in activation of transcription. Interestingly, amino acid sequence analyses of the beta-subunit demonstrate these residues to be entirely contained within the carboxyl terminus of the cDNA clone encoding the alpha-subunit.
转录因子IIA已被证明可与TATA结合蛋白相互作用，并在起始前复合物形成的早期发挥作用。人源因子由三个亚基（α、β、γ）组成。分离出了编码TFIIA最大亚基（α）的人源cDNA克隆。重组α多肽与β和γ亚基一起能够重建TFIIA活性。使用针对重组α多肽产生的抗体进行的研究表明，TFIIA可以是起始前复合物的一个组成部分。我们证明TFIIA不仅与TBP相互作用，还能与TFIID复合物结合。功能分析表明，TFIIA在基础转录中没有明显作用，但在转录激活中起重要作用。有趣的是，β亚基的氨基酸序列分析表明，这些残基完全包含在编码α亚基的cDNA克隆的羧基末端内。
