Kim T K, Roeder R G
Laboratory of Biochemistry and Molecular Biology, Rockefeller University, New York, New York 10021.
J Biol Chem. 1994 Feb 18;269(7):4891-4.
The TATA-binding protein (TBP) plays a central role in transcription initiation by nuclear RNA polymerases I, II, and III. With knowledge of the three-dimensional structure of TBP, mutational analyses were focused on the highly exposed basic repeat domain in yeast TBP in order to identify amino acid residues which could discriminate transcription functions of different RNA polymerases. One mutation (K156L) was found to specifically abolish transcription by RNA polymerase I and another mutation (K138L) specifically abolished transcription by RNA polymerase III, while each maintained the ability to support in vitro transcription by the other two RNA polymerases. Along with previous studies, these results indicate that the basic repeat domain of TBP is important not only for transcription by RNA polymerase II but also for transcription by RNA polymerases I and III and, further, that the region has distinct sites for interactions which are specific for RNA polymerases I and III.
TATA 结合蛋白（TBP）在细胞核 RNA 聚合酶 I、II 和 III 的转录起始过程中发挥核心作用。基于对 TBP 三维结构的了解，突变分析聚焦于酵母 TBP 中高度暴露的碱性重复结构域，以确定能够区分不同 RNA 聚合酶转录功能的氨基酸残基。发现一个突变（K156L）能特异性地消除 RNA 聚合酶 I 的转录，另一个突变（K138L）能特异性地消除 RNA 聚合酶 III 的转录，而每个突变体仍保留支持另外两种 RNA 聚合酶进行体外转录的能力。结合先前的研究，这些结果表明 TBP 的碱性重复结构域不仅对 RNA 聚合酶 II 的转录很重要，对 RNA 聚合酶 I 和 III 的转录也很重要，而且该区域具有与 RNA 聚合酶 I 和 III 特异性相互作用的不同位点。
