スプライシングに依存するエクソン-エクソン結合複合体におけるナンセンス媒介分解因子hUpf3の役割
V N Kim1, N Kataoka, G Dreyfuss
1Howard Hughes Medical Institute and Department of Biochemistry and Biophysics, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA.
まとめ
無意味な媒介による衰退 (NMD) は,欠陥のあるmRNAを分解する. タンパク質hUpf3は,核から出る前に,エクソンの交差点の近くにあるスプライスされたmRNAに結合することによって,mRNAスプライシングをNMDとリンクします.
科学分野:
- 分子生物学は分子生物学である.
- 遺伝子規制 遺伝子規制
- RNAの代謝について
背景:
- 無意味な媒介によるmRNA崩壊 (NMD) は,重要な細胞監視経路である.
- NMDは,早期終結コドン (PTC) を有するmRNAを排除する.
- このプロセスは,スプライシングと翻訳を,翻訳終了と組み合わせる必要があります.
研究 の 目的:
- NMD経路におけるhUpf3タンパク質の役割を調査する.
- hUpf3がmRNA処理と輸出因子との相互作用を解明する.
- hUpf3がスプライシングとNMDをどのように結びつけるかを理解する.
主な方法:
- タンパク質の相互作用を研究するための共免疫プレシピテーション.
- mRNA-タンパク質複合体の分析.
- hUpf3の細胞内の局所化に関する研究.
主要な成果:
- hUpf3は,スプライシング後のmRNP複合体の成分であるY14と相互作用する.
- hUpf3は,mRNA輸出因子Aly/REFとTAPを含むmRNP複合体で見つかりました.
- hUpf3は,Y14やAly/REFと類似して,エクソン-エクソン結合の前方にスプライスされたmRNAと結合する.
結論:
- hUpf3は,輸出を目的とした核 mRNP コンプレックスの一部です.
- 輸出前にhUpf3がmRNAに結合するスプライシング依存結合は,スプライシングをNMD.にリンクする.
- hUpf3は,mRNAスプライシングとサイトプラズマのNMDとの間の分子ブリッジとして機能します.
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