Structure-function analysis of the TBP-binding protein Dr1 reveals a mechanism for repression of class II gene transcription.
Structure-function analysis of the TBP-binding protein Dr1 reveals a mechanism for repression of class II gene transcription.
复制标题
DOI：
10.1101/gad.8.17.2097
复制
发表时间：
1994-09
影响因子：
10.5
通讯作者：
K. Yeung;Juan A. Inostroza;Fred H. Mermels;C. Kannabiran;Danny Reinberg
中科院分区：
文献类型：
--
作者：
K. Yeung;Juan A. Inostroza;Fred H. Mermels;C. Kannabiran;Danny Reinberg
DR1是II类基因的抑制子，通过一种新的机制调节转录。生化分析表明，DR1直接与多蛋白TFIID复合体相互作用。利用酵母双杂交系统，我们证明了DR1与TFIID的TATA结合蛋白(TBP)亚单位在体内发生了关联。此外，在瞬时转染法中，DR1可以抑制含和不含TATA启动子的转录。重要的是，在体内过表达TBP可以逆转DR1介导的抑制作用。通过使用不同的方法，我们在DR1中定位了抑制所需的两个不同的结构域。一个结构域是DR1-TBP相互作用所必需的，第二个结构域富含丙氨酸残基。在介导阻遏中，DR1的TBP结合域不能被异源DNA结合域所取代。我们证明了一些，但不是全部，转录激活剂可以在体内逆转DR1介导的抑制。
Dr1, a repressor of class II genes, regulates transcription by a novel mechanism. Biochemical analyses reveal that Dr1 directly interacts with the multiprotein TFIID complex. By use of the yeast two-hybrid system, we demonstrate that the association of Dr1 with the TATA-binding protein (TBP) subunit of TFIID occurs in vivo. In addition, Dr1 can repress transcription from TATA-containing as well as TATA-less promoters in transient transfection assays. Importantly, Dr1-mediated repression can be reversed by overexpression of TBP in vivo. By use of diverse approaches, we mapped two distinct domains in Dr1 required for repression. One domain is essential for the Dr1-TBP interaction, and the second is rich in alanine residues. The TBP-binding domain of Dr1 cannot be replaced by a heterologous DNA-binding domain in mediating repression. We demonstrate that some, but not all, transcriptional activators can reverse Dr1-mediated repression in vivo.