リボソームタンパク質が利用する独特の核輸入経路

M P Rout¹, G Blobel, J D Aitchison

¹Laboratory of Cell Biology, Howard Hughes Medical Institute, The Rockefeller University, New York, New York 10021, USA.

Cell

|May 30, 1997

まとめ

研究者らは,リボソームタンパク質の輸送に不可欠なKap123pが媒介する酵母における新しい核輸入経路を発見した. 関連するタンパク質Pse1pも,この重要な細胞プロセスを促進することができます.

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:

核輸送は,真核細胞の機能に不可欠である.
溶性輸送因子は,核孔複合体経由で核へのタンパク質の輸入を媒介する.

研究の目的:

イーストにおける新たな核輸入経路を特定し,特徴づけること.
核輸送における未定のタンパク質の役割を明らかにする.

主な方法:

イースト遺伝学と分子生物学技術.
タンパク質結合アッセイ.
核の局所化に関するインビボレポーターアッセイ.

主要な成果:

酵母ベータカリオフェリンKap123pによって媒介される独特の核輸入経路の特定.
Kap123pは,主にリボソーム生物生成に不可欠なリボソームタンパク質を輸入しています.
Kap123pは,輸送基板,ヌクレオポリン,Ran-GTPに直接結合する.
関連するカリオフェリンPse1pは,機能的にKap123pの代用である.

結論:

Kap123pはリボソームタンパク質の核輸入の主要な経路を表しています.
Pse1pはカリオフェリンとしても機能し,リボソームタンパク質の輸入を媒介することができます.
これらの発見は,リボソーム組立に不可欠なタンパク質輸送を制御する重要なメカニズムを明らかにしています.

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