新しい受容体媒介核タンパク質輸入経路です

V W Pollard¹, W M Michael, S Nakielny

¹Howard Hughes Medical Institute, Department of Biochemistry and Biophysics, University of Pennsylvania School of Medicine, Philadelphia 19104-6148, USA.

Cell

|September 20, 1996

まとめ

核タンパク質の輸入は,異なる経路を利用しています. hnRNP A1タンパク質の新しいM9信号は,従来の核局所信号 (NLS) に独立して,新しい受容体,トランスポートを含む核インポートを媒介する.

科学分野:

細胞生物学細胞生物学
分子生物学は分子生物学である.
バイオケミストリーバイオケミストリー

背景:

核タンパク質の輸入は,細胞機能にとって極めて重要です.
古典的な核局所化信号 (NLS) とインポートイン受容体は,ほとんどの核インポートを媒介する.
hnRNP A1タンパク質には,新しい輸送信号であるM9.9が含まれています.

研究の目的:

M9媒介による核輸入のメカニズムを調査する.
M9信号と相互作用するタンパク質を特定するために.
M9が古典的な輸入経路を利用しているかどうかを判断する.

主な方法:

hnRNP A1.1におけるM9トランスポート信号の特徴
M9相互作用タンパク質の識別と結合に関する研究.
M9を媒介する核輸入経路の分析.

主要な成果:

M9は,従来のNLSと輸入システムとは独立した経路で核輸入を仲介する.
新しい90 kDaのタンパク質であるトランスポートンは,M9に特異的に結合する.
トランスポートインは,M9を含むタンパク質の核輸入を媒介する.

結論:

少なくとも2つの異なる受容体媒介核タンパク質輸入経路があります.
トランスポートインは,M9に依存した核輸入の新たな媒介である.
トランスポートインは,hNRNP A1.1経由でmRNAのエクスポートにも役割を果たす可能性があります.

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