専用ストップコードのない遺伝子コード:文脈依存の翻訳終了
Estienne Carl Swart1, Valentina Serra2, Giulio Petroni2
1Institute of Cell Biology, University of Bern, 3012 Bern, Switzerland.
Cell
|July 19, 2016
まとめ
核の遺伝子コードは固定されていません いくつかのシリエットはストップコドンをアミノ酸として使用し,標準的な遺伝コードに挑戦し,mRNA 3'端が翻訳終了を調節するのに役立つことを示唆しています.
科学分野:
- 分子生物学
- 遺伝学
- 進化生物学
背景:
- 核の遺伝子コードは伝統的に高度に保存され,曖昧ではないと考えられています.
- 変異は存在し,特にシリエットでは,ストップコドンを感知コドンに再割り当てることができ,変異遺伝コードにつながります.
研究 の 目的:
- 毛皮動物におけるコドン再配分を停止するメカニズムを調査する.
- 変異性遺伝子のコードにおけるストップコドンとセンスのコドンをどのように区別するかを探求する.
- 遺伝コードの進化におけるmRNA 3'の役割を理解する.
主な方法:
- リボソームプロファイリングは,翻訳の動態を分析するために使用されました.
- コード配列の末端近くのストップコドン使用と枯渇パターンの分析が行われました.
主要な成果:
- 毛皮動物には3つの新しい遺伝子コードを含む7つの変種が特定されました.
- 2つの種では,すべての64のコドンが1つまたはすべてのストップコドンの認識とともに,標準のアミノ酸として効率的に翻訳されました.
- 証拠はmRNA 3'端が文脈依存のストップコドン認識に寄与することを示唆している.
結論:
- ストップコドンの再配分は,以前考えられていたよりも一般的です.
- 文脈に依存するメカニズムは,mRNA 3' 末端を含む可能性があり,翻訳終了と読み通しを調節する上で重要な役割を果たします.
- これらのメカニズムは遺伝子コードの進化と 新種の遺伝子コードの出現を容易にする.
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