隣接するコドンは酵母における翻訳効率を調節するために協働する
Caitlin E Gamble1, Christina E Brule2, Kimberly M Dean2
1Departments of Genome Sciences and Medicine, University of Washington, Seattle, WA 98195, USA; Program in Molecular and Cellular Biology, University of Washington, Seattle, WA 98195, USA.
Cell
|July 5, 2016
まとめ
隣接するコドンペアは,以前の仮定に反して,翻訳効率に大きな影響を与えます. この発見は タンパク質の産生と遺伝子発現に影響する 複雑な相互作用を強調しています
科学分野:
- 分子生物学
- 遺伝学
- 生物化学
背景:
- 翻訳延長効率は以前は個々のコドン解読の添加関数と考えられていた.
- 隣接するコドンの翻訳速度と精度を調節する役割は,ほとんど未知のままでした.
研究 の 目的:
- 隣接するコドンペアの変換延長効率への影響を調査する.
- タンパク質発現レベルに影響を与える特定のコドンペアを特定する.
主な方法:
- Saccharomyces cerevisiaeにおける高通量スクリーニングアプローチを使用した.
- 表現レベルを評価するために35,000以上の緑色光タンパク質 (GFP) の3つの隣接するコドンをランダム化しました.
- 内部遺伝子のリボソームプロファイリングデータを分析した.
主要な成果:
- 17組の隣接するコドンが特定され,表現が著しく低下した.
- ペア内のコドンの順番が,しばしば観察された抑制に決定的であることを示した.
- 移転RNA (tRNA) レベルの増加または非ネイティブtRNAの導入は,GFP発現を回復させることができ,トランスレーション中に効果が発生することを示した.
- 固有の遺伝子の特定の隣接コドンペアの抑制効果が確認されました.
結論:
- 隣接するコドンペアは 単一のコドンではなく 翻訳効率を調節する上で重要な役割を果たします
- リボソームの隣接するコドンと相互作用するtRNAの相互作用がタンパク質合成に影響する.
- これらの発見は,遺伝子機能とタンパク質生産に対するコドン選択の影響を再評価する必要がある.
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