転写する哺乳類RNAポリメラーゼIIの構造
Carrie Bernecky1, Franz Herzog2, Wolfgang Baumeister3
1Max Planck Institute for Biophysical Chemistry, Department of Molecular Biology, Am Faßberg 11, 37077 Göttingen, Germany.
Nature
|January 21, 2016
まとめ
研究者は,哺乳類のRNAポリメラーゼII (Pol II) の高解像度冷凍電子顕微鏡構造を決定した. これは酵母Pol IIと保存された特徴と,真核生物の遺伝子転写に不可欠な新しい相互作用を明らかにしています.
科学分野:
- 分子生物学
- 構造生物学
- 生物化学
背景:
- RNAポリメラーゼII (Pol II) の高解像度構造は,酵母系では確立されているが,哺乳類系では限られている.
- 以前の哺乳類Pol IIの研究では,低解像度の電子顕微鏡を用いて詳細な機械的洞察を阻害していました.
研究 の 目的:
- 転写複合体における哺乳類のPol IIの高解像度冷凍電子顕微鏡構造を決定する.
- 核酸結合と転写因子との相互作用の構造的基礎を解明する.
主な方法:
- クリオ電子顕微鏡 (cryo-EM) 3.4 Åの解像度で
- 牛のPol II転写複合体の原子モデル再構築 (ヒトのPol IIと非常に似ている).
主要な成果:
- 哺乳類のポルII構造は酵母ポルIIに非常に似ていますが,ユニークな特徴があります.
- 核酸結合には,Pol IIクランプとアクティブセンターの誘導的適合が含まれます.
- RPB5の保存されたTPSAモチーフは下流DNAと相互作用し,上流DNAの位置はDSIF結合を可能にします.
結論:
- この研究では,哺乳類のPol IIの機能的構造を定義し,真核転写における酵母Pol IIの関連性を確認した.
- 哺乳類における転写の開始と延長を理解するための構造的基礎を提供します.
- 人間の転写のメカニズム的研究のための基礎を提供している.
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