-1のダイナミック経路は,トランスレーションフレームシフト.
Jin Chen1, Alexey Petrov2, Magnus Johansson2
11] Department of Applied Physics, Stanford University, Stanford, California 94305-4090, USA [2] Department of Structural Biology, Stanford University School of Medicine, Stanford, California 94305-5126, USA.
Nature
|June 12, 2014
まとめ
プログラムされた-1リボソームのフレームシフトは,リボソームが一時停止し,特定のmRNA配列の構造変化を起こし,新しいアミノ酸配列の翻訳を可能にすると起こります.
科学分野:
- 分子生物学は分子生物学である.
- 遺伝学 遺伝学とは
- バイオケミストリー バイオケミストリー
背景:
- リボソームのフレームシフトは,希少ですが,翻訳のプログラムされたイベントであり,滑りやすい配列のようなmRNA構造の影響を受けます.
- プログラムされた-1フレームシフトのメカニズムは,広範な研究にもかかわらず,不明のままです.
研究 の 目的:
- -1フレームシフト中のリボソームのメカニズムと構成のダイナミクスを解明する.
- フレームシフト誘発mRNA翻訳中の個々のコドンにおけるリボソームの行動を調査する.
主な方法:
- 単分子光顕微鏡を用いてリボソームの動態を追跡した.
- Escherichia coli dnaX mRNAの翻訳中のリボソームの停止,サブユニット回転,tRNA相互作用の分析.
主要な成果:
- フレームシフトリボソームは,非フレームシフトリボソームと比較して10倍も長い一時停止を示した.
- リボソーム-mRNAの相互作用は,一時的な解離トランスロケーションとサブユニット回転の間に起こり,非正規の状態を生み出します.
- tRNAサンプリングとAサイトでのEF-G作用により, -1フレームへのフレームシフトまたは0フレームでの継続が決定されました.
結論:
- -1 リボソームフレームシフトのメカニズムと構成の枠組みが確立されました.
- 伸縮中の複数の運動分岐点は,フレームシフトにとって決定的に重要であると特定されました.
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