コード化されていない翻訳の緩和
Jordan S Kesner1,2, Ziheng Chen1,2,3, Peiguo Shi1,2
1Cardiometabolic Genomics Program, Division of Cardiology, Department of Medicine, Columbia University Irving Medical Center, New York, NY, USA.
Nature
|April 12, 2023
まとめ
非コーディングDNA領域からの翻訳は特に癌のような病気で頻繁に起こります この研究は,退化または膜の局所化のために異常なポリペプチドを標的とする,水害性C端尾を含む監視メカニズムを明らかにしています.
科学分野:
- 遺伝学
- 分子生物学
- 生物化学
背景:
- 翻訳は,長いノンコーディングRNA,翻訳されていない領域,およびイントロンを含む,正規のコーディング領域を超えて発生します.
- この非正規的な翻訳は老化,神経変性,癌に絡み合っており,多くの腫瘍特異性抗原がそこから発生しています.
- ノンコーディング翻訳と結果のポリペプチドの機能的進化を監視するメカニズムは,ほとんど不明のままである.
研究 の 目的:
- 非コード翻訳の監視メカニズムを調査する.
- ノンコーディング領域からのポリペプチドが新しい機能を取得する方法を理解する.
- これらの新しいポリペプチドの局所化を制御する生化学的経路を解明する.
主な方法:
- 1万以上のヒトゲノムと 数百万のランダムな配列の 膨大な並行分析を統合したものです
- ゲノム全体のCRISPRスクリーンです
- 詳細な遺伝子と生化学的特徴
主要な成果:
- ノンコーディングゲノムと遺伝子コードの内在的なヌクレオチドバイアスは,しばしば水害性C端尾を持つポリペプチドを生成する.
- BAG6膜タンパク質トリアージ複合体は,これらの水害性尾を捕捉し,分解または膜標的化のためにポリペプチドを誘導します.
- カノニカルタンパク質はC末端の水性残基を欠くように進化し,非コーディング変換産物と区別される.
結論:
- 異なった非コーディングゲノム領域からの望ましくない翻訳に対して,安全監視メカニズムが存在します.
- このメカニズムには,BAG6複合体と水害性C端尾認識が含まれています.
- 新しく進化したタンパク質の優先膜局所化のための潜在的な生化学的経路が特定される.
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