The Zta trans-activator protein stabilizes TFIID association with promoter DNA by direct protein-protein interaction.
The Zta trans-activator protein stabilizes TFIID association with promoter DNA by direct protein-protein interaction.
复制标题
Zta 反式激活蛋白通过直接的蛋白质-蛋白质相互作用稳定 TFIID 与启动子 DNA 的结合。
DOI：
10.1101/gad.5.12b.2441
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发表时间：
1991
影响因子：
10.5
通讯作者：
Berk,AJ
中科院分区：
文献类型：
--
作者：
Lieberman,PM;Berk,AJ
真核转录激活剂被认为通过与一个或多个一般转录因子直接和/或间接相互作用来刺激转录。我们在这里证明了由Epstein-Barr病毒编码的Zta转录激活蛋白与基本转录因子TFIID直接物理接触。Zta和TFIID均在大肠杆菌中表达和纯化。Zta稳定了TFIID与Zta反应启动子的结合，通过凝胶电泳、迁移率漂移和放射性标记启动子DNA的免疫沉淀检测。Zta的一个未能激活转录的缺失突变体无法稳定TFIID结合。DNase I足迹显示，Zta降低了TFIID与TATA元件结合的解离速率。蛋白质印迹和免疫沉淀实验表明，在没有启动子DNA的情况下，TFIID和Zta也可以相互作用。Zta的25-86位氨基酸残基是与TFIID稳定结合所必需的，也是体内反式激活所必需的。我们认为，Zta通过直接与TFIID的保守结构域接触并形成稳定的Zta-TFIID-启动子复合体来刺激转录。
Eukaryotic transcriptional activators are believed to stimulate transcription through direct and/or indirect interactions with one or more of the general transcription factors. We show here that the Zta transcriptional activator protein encoded by the Epstein-Barr virus makes direct physical contact with the basic transcription factor TFIID. Both Zta and TFIID were expressed in and purified from Escherichia coli. Zta stabilized the binding of TFIID to Zta-responsive promoters as assayed by gel electrophoresis mobility-shift and immunoprecipitation of radiolabeled promoter DNA. A deletion mutant of Zta that failed to activate transcription failed to stabilize TFIID binding. DNase I footprinting showed that Zta reduced the dissociation rate of TFIID bound to the TATA element. Protein blotting and immunoprecipitation experiments demonstrated that TFIID and Zta also interact in the absence of promoter DNA. The amino acid residues 25-86 of Zta were essential for the stable association with TFIID and were shown to be required for trans-activation in vivo. We propose that Zta stimulates transcription, in part, by direct physical contact with the conserved domain of TFIID and the formation of a stable Zta-TFIID-promoter complex.