翻訳開始は,リボソーム起草メカニズムによるRNA折り畳み運動によって制御されます
Amin Espah Borujeni1, Howard M Salis1
1Department of Chemical Engineering and ‡Department of Biological Engineering, The Pennsylvania State University , University Park, Pennsylvania 16802, United States.
Journal of the American Chemical Society
|May 21, 2016
まとめ
リボソーム起草は,mRNAへの急速なリボソーム結合により,タンパク質合成が加速される新しいメカニズムです. この非均衡の過程で タンパク質の生産速度が1000倍に変化し 遺伝子発現に影響を与えます
科学分野:
- 分子生物学
- バイオ物理学
- システム生物学
背景:
- RNAの折り畳みは タンパク質合成を含む細胞のプロセスに不可欠です
- 現在のモデルでは,トランスレーションに対する非均衡RNAの折りたたみ効果がしばしば見過ごされている.
- 翻訳開始率は,主に均衡状態で研究されます.
研究 の 目的:
- "リボソーム起草"メカニズムを紹介し説明する.
- RNAの折りたたみ運動とリボソーム結合が共同で翻訳を制御する方法を研究する.
- 不均衡のRNAの折りたたみがタンパク質合成速度に与える影響を調べる.
主な方法:
- リボソーム結合率と折りたたみ特性を有するmRNAの計算設計.
- RNAの折り畳みダイナミクスを研究するための時間相関単一光子のカウント.
- タンパク質合成率を定量化するための遺伝子発現測定
主要な成果:
- ゆっくりと折りたたむ RNA 構造と速く折りたたむ RNA 構造は,似たような折りたたみエネルギーの場合でも,タンパク質合成速度の 1000 倍もの違いを生むことが示されました.
- mRNAの性質を特徴づけることでリボソームの起草に必要な条件を特定した.
- 不均衡のマルコフモデルによる予測を検証した.
結論:
- リボソーム起草は,翻訳開始を制御する重要な非均衡メカニズムです.
- 競争的な折りたたみと組み立て動態は,遺伝子発現配列-構造-機能関係に大きな影響を与える.
- この発見は,細胞の遺伝子発現機構を理解する上で大きな意味を持つ.
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