CRM1は,レウシンに富んだ核輸出信号の輸出受容体である
M Fornerod1, M Ohno, M Yoshida
1European Molecular Biology Laboratory, Heidelberg, Germany.
Cell
|October 10, 1997
まとめ
CRM1は核輸出受容体として作用し,特定の分子の核の外への輸送を促進します. レプトミシンBは,このプロセスを阻害し,CRM1を明らかにします.
科学分野:
- 分子生物学は分子生物学である.
- 細胞生物学 細胞生物学
- バイオケミストリー バイオケミストリー
背景:
- 核輸入受容体に関連するタンパク質であるCRM1は,核孔複合体と相互作用する.
- 核の輸出におけるCRM1の役割は,以前,核毛孔複合体との相互作用によって示唆されていた.
研究 の 目的:
- 核輸出受容体としてのCRM1の機能を調査する.
- RanGTPの役割を含むCRM1を媒介する核輸出のメカニズムを解明する.
主な方法:
- 過剰発現によるXenopus卵細胞におけるCRM1の機能を研究した.
- 核輸出を抑制するために,CRM1結合性サイトトキシンであるレプトミシンBを使用した.
- RanGTPと核輸出信号 (NES) のCRM1複合形成を分析するために,in vitro結合測定を行った.
主要な成果:
- CRM1の過剰発現は,Xenopusの卵細胞からのRevとU snRNAの輸出を刺激した.
- レプトミシンBは,RevとU snRNAの核輸出を特に抑制しました.
- In vitroでは,CRM1はレプトミシンBに敏感な方法でRanGTPとNESを含むタンパク質 (Rev,PKI) と複合体を形成した.
結論:
- CRM1は,レウシンに富んだ核輸出信号 (NES) を含むタンパク質の輸出受容体として機能する.
- RanGTPはCRM1による核輸出において重要な役割を果たしています.
- 原子力輸出におけるCRM1機能のモデルが提案されています.
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