5'キャップのm6Amの可逆メチル化はmRNAの安定性を制御する
Jan Mauer1, Xiaobing Luo2, Alexandre Blanjoie3
1Department of Pharmacology, Weill Cornell Medicine, Cornell University, New York, New York 10065, USA.
Nature
|December 22, 2016
まとめ
mRNAの5'端のN6,2'- O- ディメチラデノシン (m6Am) 変異は,切断に抵抗することで,転写の安定性を高める. 脂肪と肥満に関連したタンパク質 (FTO) は,このm6Amマークを逆転させ,mRNAの運命を影響します.
科学分野:
- 分子生物学
- エピジェネティクス
- RNA 生物学
背景:
- mRNAの内部塩基は細胞の運命を左右する修正を受けます.
- N6,2"-O-ジメチラデノシン (m6Am) は,7メチルグアノシンキャップの隣接するmRNAの5'端で流行している変異です.
研究 の 目的:
- 細胞のmRNA運命を左右する可逆的な変異として,N6,2"-O-ジメチラデノシン (m6Am) の役割を調査する.
- m6AmがmRNAの安定性とその調節に与える影響を決定する.
主な方法:
- トランスクリプトーム全体のm6Am改変のマッピング
- m6Am状態との関係でmRNAの安定性を評価する.
- m6Amとデカッピング酵素DCP2の相互作用を調査する.
- 脂肪質と肥満に関連するタンパク質 (FTO) の脱メチル化活性をm6Amで分析する.
主要な成果:
- m6Amで開始されたトランスクリプトは,他のヌクレオチドで開始されたトランスクリプトと比較して,著しく安定性を発揮します.
- m6Amトランスクリプトの安定性の向上は,mRNA分解酵素DCP2に対する耐性によるものである.
- 脂肪質と肥満に関連したタンパク質 (FTO) は選択的にm6Amを脱メチル化し,これはN6-メチラデノシン (m6A) に対する作用とは異なるプロセスである.
- FTO媒介によるm6Amの脱メチル化は,mRNAの安定性を低下させる.
結論:
- 5'キャップのm6Amのメチル化状態は,ダイナミックで可逆的な表表表記学的変化である.
- m6Amの改変は,脱皮プロセスに影響することによって,mRNAの安定性を直接決定する.
- FTOは,m6Amのダイナミックな脱メチル化によってmRNAの安定性を調節する上で重要な役割を果たします.
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