Structural insight into nucleosome transcription by RNA polymerase II with elongation factors
Structural insight into nucleosome transcription by RNA polymerase II with elongation factors
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DOI：
10.1126/science.aav8912
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发表时间：
2019-02-15
期刊：
影响因子：
56.9
通讯作者：
Sekine, Shun-ichi
中科院分区：
文献类型：
--
作者：
Ehara, Haruhiko;Kujirai, Tomoya;Sekine, Shun-ichi
RNA聚合酶II（RNAPII）转录含有多个核小体的染色体DNA。核小体形成转录屏障，并且核小体转录需要体内的几个额外的因子。我们证明，转录延伸因子Elf 1和Spt 4/5合作降低的障碍，并增加RNAPII在核小体的加工能力。核小体转录RNAPII延伸复合物（EC）的冷冻电子显微镜结构显示，Elf 1和Spt 4/5重塑EC下游边缘和RNAPII和核小体之间的干预。它们通过调节核小体促进RNAPII通过超螺旋位置SHL（-1）的前进。它们通过阻止稳定的RNAPII-核小体相互作用来抑制在SHL（-5）处的暂停。因此，EC克服了核小体屏障，同时为各种染色质功能提供了平台。
RNA polymerase II (RNAPII) transcribes chromosomal DNA that contains multiple nucleosomes. The nucleosome forms transcriptional barriers, and nucleosomal transcription requires several additional factors in vivo. We demonstrate that the transcription elongation factors Elf1 and Spt4/5 cooperatively lower the barriers and increase the RNAPII processivity in the nucleosome. The cryo-electron microscopy structures of the nucleosome-transcribing RNAPII elongation complexes (ECs) reveal that Elf1 and Spt4/5 reshape the EC downstream edge and intervene between RNAPII and the nucleosome. They facilitate RNAPII progression through superhelical location SHL(-1) by adjusting the nucleosome in favor of the forward progression. They suppress pausing at SHL(-5) by preventing the stable RNAPII-nucleosome interaction. Thus, the EC overcomes the nucleosomal barriers while providing a platform for various chromatin functions.