Strubin M, Struhl K
Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts 02115.
Cell. 1992 Feb 21;68(4):721-30. doi: 10.1016/0092-8674(92)90147-5.
TFIID is the highly conserved, but species-specific, component of the RNA polymerase II transcription machinery that binds specifically to the TATA element (consensus TATAAA). Using a genetic selection, we isolated an altered specificity derivative of yeast TFIID that permits transcription from promoters containing a mutated TATA element (TGTAAA). Biochemical analysis indicates that this TFIID derivative has specifically gained the ability to bind TGTAAA efficiently. The mutant protein contains three substitutions within a 12 amino acid region; two of these are necessary and primarily responsible for the altered specificity. An analogous version of human TFIID, generated by introducing the same amino acid substitutions in the corresponding region of the protein, can support basal and GCN4-activated transcription in yeast cells from a TGTAAA-containing promoter. These results define a surface of TFIID that directly interacts with the TATA element, and they indicate that human TFIID can respond to acidic activator proteins in conjunction with the other components of the yeast transcription machinery.
TFIID是RNA聚合酶II转录机制中高度保守但具有物种特异性的成分，它能特异性结合TATA元件（共有序列TATAAA）。通过基因筛选，我们分离出了酵母TFIID的一种特异性改变的衍生物，它能从含有突变TATA元件（TGTAAA）的启动子进行转录。生化分析表明，这种TFIID衍生物特别获得了高效结合TGTAAA的能力。该突变蛋白在一个12个氨基酸的区域内有三个替换；其中两个是必需的，并且主要负责特异性的改变。通过在蛋白质的相应区域引入相同的氨基酸替换而产生的人TFIID的类似版本，可以支持酵母细胞中来自含TGTAAA启动子的基础转录和GCN4激活的转录。这些结果确定了TFIID与TATA元件直接相互作用的一个表面，并且表明人TFIID可以与酵母转录机制的其他成分一起对酸性激活蛋白作出反应。
