1] Gene Center Munich and Department of Biochemistry, Center for Integrated Protein Science CIPSM, Ludwig-Maximilians-Universität München, Feodor-Lynen-Strasse 25, 81377 Munich, Germany [2] [3].
Gene Center Munich and Department of Biochemistry, Center for Integrated Protein Science CIPSM, Ludwig-Maximilians-Universität München, Feodor-Lynen-Strasse 25, 81377 Munich, Germany.
Nat Commun. 2014 Jul 10;5:4310. doi: 10.1038/ncomms5310.
During transcription initiation at promoters of protein-coding genes, RNA polymerase (Pol) II assembles with TBP, TFIIB and TFIIF into a conserved core initiation complex that recruits additional factors. The core complex stabilizes open DNA and initiates RNA synthesis, and it is conserved in the Pol I and Pol III transcription systems. Here, we derive the domain architecture of the yeast core pol II initiation complex during transcription initiation. The yeast complex resembles the human initiation complex and reveals that the TFIIF Tfg2 winged helix domain swings over promoter DNA. An 'arm' and a 'charged helix' in TFIIF function in transcription start site selection and initial RNA synthesis, respectively, and apparently extend into the active centre cleft. Our model provides the basis for further structure-function analysis of the entire transcription initiation complex.
在蛋白质编码基因启动子处的转录起始过程中，RNA 聚合酶（Pol）II 与 TBP、TFIIB 和 TFIIF 组装成一个保守的核心起始复合物，该复合物招募额外的因子。核心复合物稳定开放的 DNA 并起始 RNA 合成，并且在 Pol I 和 Pol III 转录系统中保守。在这里，我们在转录起始过程中推导出酵母核心 pol II 起始复合物的结构域架构。酵母复合物类似于人类起始复合物，并揭示了 TFIIF Tfg2 的翼状螺旋结构域在启动子 DNA 上摆动。TFIIF 的“臂”和“带电螺旋”分别在转录起始位点选择和初始 RNA 合成中起作用，并且显然延伸到活性中心裂隙中。我们的模型为整个转录起始复合物的进一步结构功能分析提供了基础。
