Molecular Biophysics and Integrative Bio-Imaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA; Howard Hughes Medical Institute, University of California, Berkeley, CA 94720, USA; California Institute for Quantitative Biosciences (QB3), University of California, Berkeley, CA 94720, USA.
Molecular Biophysics and Integrative Bio-Imaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA; California Institute for Quantitative Biosciences (QB3), University of California, Berkeley, CA 94720, USA.
Curr Opin Struct Biol. 2020 Apr;61:17-24. doi: 10.1016/j.sbi.2019.10.001. Epub 2019 Nov 18.
TFIID is a large multiprotein assembly that serves as a general transcription factor for transcription initiation by eukaryotic RNA polymerase II (Pol II). TFIID is involved in the recognition of the core promoter sequences and neighboring chromatin marks, and can interact with gene-specific activators and repressors. In order to obtain a better molecular and mechanistic understanding of the function of TFIID, its structure has been pursued for many years. However, the scarcity of TFIID and its highly flexible nature have made this pursuit very challenging. Recent breakthroughs, largely due to methodological advances in cryo-electron microscopy, have finally described the structure of this complex, both alone and engaged with core promoter DNA, revealing the functional significance of its conformational complexity in the process of core promoter recognition and initiation of Pol II transcription. Here, we review these recent structural insights and discuss their implications for our understanding of eukaryotic transcription initiation.
TFIID 是一个大型的多蛋白复合物,作为真核 RNA 聚合酶 II (Pol II) 转录起始的通用转录因子。TFIID 参与识别核心启动子序列和相邻的染色质标记,并可以与基因特异性激活剂和抑制剂相互作用。为了更好地了解 TFIID 的分子和机制功能,多年来一直致力于研究其结构。然而,TFIID 的稀缺性及其高度灵活的性质使得这一研究极具挑战性。最近的突破,主要得益于低温电子显微镜方法学的进步,终于描述了该复合物的结构,包括单独的和与核心启动子 DNA 结合的结构,揭示了其构象复杂性在核心启动子识别和 Pol II 转录起始过程中的功能意义。在这里,我们回顾这些最近的结构见解,并讨论它们对我们理解真核转录起始的意义。