核輸入は,in vitroでは,核孔結合と転位という異なる段階に分けることができる

D D Newmeyer¹, D J Forbes

¹Department of Biology, University of California at San Diego, La Jolla 92093.

Cell

|March 11, 1988

まとめ

核タンパク質の輸送には2つの段階があります:信号配列に依存した結合と,核孔を通るATPを必要とする転位です. WGAレクチンは転位を阻害しますが,結合しません.

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:

核タンパク質は,核への転位のために特定の信号を必要とします.
核孔複合体は,原子核と細胞プラズマの間の分子の通過を調節する.

研究の目的:

核タンパク質輸送の異なる段階を解剖する.
核インポートにおける信号配列とATPの役割を調査する.

主な方法:

核タンパク質の輸送を研究するために in vitro システムを活用しました.
視覚化のために光と電子顕微鏡を用いた.
テストされた天然 (ヌクレオプラズミン) および合成 (SV40 T抗原信号配列-HSA) タンパク質.
ミュータントの信号配列とWGAレクチンの効果を調査した.

主要な成果:

核タンパク質の輸入は,信号依存の結合とATP依存の転位という2段階で行われます.
結合と転位の両方には,機能的な信号配列が必要です.
小麦芽アグルチニン (WGA) は,転位ステップを阻害するが,初期結合は阻害しない.

結論:

核タンパク質の輸入は,異なる結合と転位相を含む多段階のプロセスです.
信号配列は,核孔への結合と,核孔を通過する転位の両方に極めて重要です.
ATPは転位ステップに不可欠であり,WGAは特にこの段階をターゲットとしています.

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