Department of Functional Genomics and Cancer, IGBMC, CNRS/INSERM/University of Strasbourg, BP 163, 67404, Illkirch Cedex, C. U. Strasbourg, France.
Nat Commun. 2019 May 7;10(1):2084. doi: 10.1038/s41467-019-10131-1.
In eukaryotes, the general transcription factors TFIIE and TFIIH assemble at the transcription start site with RNA Polymerase II. However, the mechanism by which these transcription factors incorporate the preinitiation complex and coordinate their action during RNA polymerase II transcription remains elusive. Here we show that the TFIIEα and TFIIEβ subunits anchor the TFIIH kinase module (CAK) within the preinitiation complex. In addition, we show that while RNA polymerase II phosphorylation and DNA opening occur, CAK and TFIIEα are released from the promoter. This dissociation is impeded by either ATP-γS or CDK7 inhibitor THZ1, but still occurs when XPB activity is abrogated. Finally, we show that the Core-TFIIH and TFIIEβ are subsequently removed, while elongation factors such as DSIF are recruited. Remarkably, these early transcriptional events are affected by TFIIE and TFIIH mutations associated with the developmental disorder, trichothiodystrophy.
在真核生物中，一般转录因子 TFIIE 和 TFIIH 与 RNA 聚合酶 II 一起在转录起始位点组装。然而，这些转录因子将起始前复合物组装在一起并协调它们在 RNA 聚合酶 II 转录过程中的作用的机制仍然难以捉摸。在这里，我们表明 TFIIEα 和 TFIIEβ 亚基将 TFIIH 激酶模块 (CAK) 锚定在起始前复合物内。此外，我们表明，当 RNA 聚合酶 II 磷酸化和 DNA 打开时，CAK 和 TFIIEα 从启动子上释放。这种解离受到 ATP-γS 或 CDK7 抑制剂 THZ1 的阻碍，但当 XPB 活性被阻断时仍会发生。最后，我们表明核心-TFIIH 和 TFIIEβ 随后被去除，而伸长因子如 DSIF 被募集。值得注意的是，这些早期转录事件受与发育障碍毛发硫营养不良相关的 TFIIE 和 TFIIH 突变的影响。
