総合的なアプローチでは,細菌の翻訳延伸に対する規制管理が明らかになる
Arvind R Subramaniam1, Brian M Zid1, Erin K O'Shea2
1Faculty of Arts and Sciences Center for Systems Biology, Harvard University, Cambridge, MA 02138, USA; Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138, USA.
Cell
|November 24, 2014
まとめ
リボソームの伸び率は,トランスレーション中に変化します. この研究は,アミノアシレーション運動学と翻訳中絶がタンパク質合成を調節することを明らかにし,特にE. coliの栄養ストレス中にタンパク質合成を調節します.
科学分野:
- 分子生物学は分子生物学である.
- システム生物学 システム生物学
- コンピュータ生物学 コンピュータ生物学
背景:
- リボソームの伸び率は,トランスレーション中に不均一である.
- 理論モデルと実験データには,延伸率のインビボ決定因子とタンパク質レベルへの影響に関する不一致がある.
研究 の 目的:
- トランスレーション伸縮率の決定因子とメカニズムに関する紛争を解決する.
- タンパク質濃度に対する延長速度の影響を調査する.
- E. coli. の全細胞翻訳モデルを開発する.
主な方法:
- 様々な条件下で,トランスクリプトーム全体のリボソーム占有率を測定した.
- E. coliにおけるトランスレーションの全細胞モデルを策定した.
- 飢餓中のtRNAアミノアシレーション運動に対する延長停止の感受性を分析した.
主要な成果:
- 栄養豊富な成長中のほとんどのコドンの延長率は,アミノアシル-tRNA濃度によって制限されません.
- アミノ酸飢餓中の延長停止は,tRNAアミノアシレーション運動性に敏感です.
- トランスレーション・アボルト・オン・パウシングは,飢餓中のリボソームの占拠を説明する.
- 妊娠中絶は全身のタンパク質合成を減少させますが,特定のmRNAsの翻訳を高めます.
結論:
- アミノアシレーションと中絶は,ストレスのときの調節的な役割を果たします.
- この研究は,翻訳をモデル化するための実験的に制約された枠組みを提供します.
- 非均一なリボソーム延長率は,栄養素の利用可能性とtRNAのダイナミクスによって影響を受けます.
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