Deng Wensheng, Roberts Stefan G E
Faculty of Life Sciences, University of Manchester, The Michael Smith Building, Oxford Road, Manchester, M13 9PT, UK.
Chromosoma. 2007 Oct;116(5):417-29. doi: 10.1007/s00412-007-0113-9. Epub 2007 Jun 26.
Accurate transcription of a gene by RNA polymerase II requires the assembly of a group of general transcription factors at the promoter. The general transcription factor TFIIB plays a central role in preinitiation complex assembly, providing a bridge between promoter-bound TFIID and RNA polymerase II. TFIIB makes extensive contact with the core promoter via two independent DNA-recognition modules. In addition to interacting with other general transcription factors, TFIIB directly modulates the catalytic center of RNA polymerase II in the transcription complex. Moreover, TFIIB has been proposed as a target of transcriptional activator proteins that act to stimulate preinitiation complex assembly. In this review, we will discuss our current understanding of these activities of TFIIB.
RNA聚合酶II对基因的准确转录需要在启动子处组装一组通用转录因子。通用转录因子TFIIB在起始前复合物组装中起核心作用，在结合于启动子的TFIID和RNA聚合酶II之间搭建桥梁。TFIIB通过两个独立的DNA识别模块与核心启动子广泛接触。除了与其他通用转录因子相互作用外，TFIIB还直接调节转录复合物中RNA聚合酶II的催化中心。此外，TFIIB被认为是转录激活蛋白的作用靶点，这些蛋白可刺激起始前复合物的组装。在本综述中，我们将讨论目前对TFIIB这些活性的理解。
