タンパク質翻訳の効率を制御するための進化的に保存されたメカニズムです
Tamir Tuller1, Asaf Carmi, Kalin Vestsigian
1Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 76100, Israel.
Cell
|April 21, 2010
まとめ
この研究では,メッセンジャーRNA (mRNA) に沿って翻訳効率のプロファイルが保存され,真核生物の遅い開始と速い終了を示しています. このコーディングシーケンス機能は,リボソームの交通渋滞を防ぐことでタンパク質発現を最適化します.
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
- バイオフィジックス 生物物理学
背景:
- タンパク質翻訳の測定は著しく進歩しました.
- 翻訳効率におけるコード配列の役割は十分に理解されていません.
研究 の 目的:
- メッセンジャーRNA (mRNA) 沿いの翻訳効率の保存パターンを特定する.
- コーディングシーケンス,転送RNA (tRNA) の可用性,および翻訳速度との関係を調査する.
- これらのパターンがリボソーム密度とタンパク質発現にどのように影響するかを理解する.
主な方法:
- mRNAのコード配列とtRNAプールに基づいて,翻訳効率の普遍的に保存されたプロファイルを計算した.
- 全体のコーディングシーケンスの効率プロファイルを分析しました.
- イースト遺伝子の位置依存リボソーム密度を予測することによってプロフィールを検証しました.
主要な成果:
- mRNAsに沿って保存された翻訳効率プロファイルが特定されました.
- 最初の30〜50コドンは,低効率で翻訳されます.
- ユカリオットでは,最後の ~50 のコドンが最も高い翻訳効率を示します.
- このプロファイルは,酵母遺伝子を沿ってリボソームの密度を正確に予測します.
結論:
- 翻訳速度とリボソーム密度は,mRNAのコード配列とtRNAプールでコードされます.
- mRNAの開始時の遅い"ランプ"は,遅い翻訳開始ステップとして機能します.
- このメカニズムは,コストを最小限に抑え,リボソームの"交通渋滞"を防ぐことで,タンパク質発現を最適化します.
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