プログラムされた-1フレームシフトは,阻害されたトランスロケーションの際に,運動分割によるフレームシフト.
Neva Caliskan1, Vladimir I Katunin2, Riccardo Belardinelli1
1Max Planck Institute for Biophysical Chemistry, Department of Physical Biochemistry, 37077 Göttingen, Germany.
Cell
|June 21, 2014
まとめ
プログラムされた-1リボソームフレームシフト (-1PRF) は,細胞がゲノム情報を拡張し,遺伝子発現を調節することを可能にします. この研究は,1PRFがmRNA構造とリボソーム動力学の影響を受け,翻訳延伸の遅い段階で発生することを明らかにしています.
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:
- プログラムされた-1リボソームフレームシフト (-1PRF) は,mRNA再コーディングの重要なメカニズムです.
- ゲノム情報の内容を高め,遺伝子発現を調節する.
- トランスレーション延長中の1PRFの正確なタイミングとメカニズムは,まだ完全に理解されていません.
研究 の 目的:
- プログラムされた-1リボソームのフレームシフトを制御するステップ・バイ・ステップのメカニズムを解明する.
- 翻訳延長プロセス中の -1PRF のタイミングを決定する.
- −1PRFの調節におけるpseudoknotsのようなmRNA二次構造の役割を調査する.
主な方法:
- Escherichia coli.から再構成された in vitro 翻訳システムを利用しました.
- IBV 1a/1b遺伝子から派生したモデルmRNAを使用した.
- フレームシフト部位を通してリボソームの段階的な動きを追跡した.
主要な成果:
- フレームシフトを後期的な転位イベントとして識別した.
- フレームシフトは,tRNAが隣接する滑りやすいコドンを占有するときに発生することを実証しました.
- 下流の擬似結が30Sサブユニットヘッドの閉塞,EF-G解離,tRNAの放出を妨げることを示した.
- リボソームが -1 フレームに滑り込むことが転位完了を加速し,新しい読み取りフレームを好むことを発見しました.
結論:
- プログラムされた-1リボソームフレームシフトは,翻訳延長の遅い段階で発生する規制されたプロセスです.
- mRNAの二次構造は,フレームシフトの動力学に大きな影響を与えます.
- リボソームのダイナミクスと延伸因子との相互作用は,1PRFの効率化に不可欠です.
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