ニカストリンは,ガンマ分泌酵素基板受容体として機能する
Sanjiv Shah1, Sheu-Fen Lee, Katsuhiko Tabuchi
1Center for Basic Neuroscience, The University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA.
Cell
|August 13, 2005
まとめ
ニカストリンは,アミロイド前駆タンパク質 (APP) とノッチ基板の受容体として作用します. そのエクトドメインは,割れた基板に結合し,それらを膜内タンパク質分解のためのガンマ分泌酵素複合体に徴用します.
科学分野:
- 分子および細胞生物学
- 神経科学は神経科学である.
背景:
- ガンマ分泌酵素は,アミロイド前駆タンパク質 (APP) とNotch.の膜内分裂を行う.
- ニカストリンは,ガンマ分泌酵素複合体の既知の成分で,その役割は不明である.
研究 の 目的:
- ガンマ分泌酵素複合体内のニカストリンの機能を明らかにする.
- ガンマ分泌酵素媒介による裂解のために基板がどのように採用されるかを調査する.
主な方法:
- ニカストリンのエクトドメインと基質アミノ・ターミニとの相互作用を調査した.
- 化学的および抗体阻害戦略を活用した.
- ニカストリンのエクトドメインの変異分析を行った.
主要な成果:
- ニカストリンのエクトドメインは,割れたAPPとNotch基板の新たに生成されたアミノ末端に結合します.
- この結合は,ガンマ分泌酵素複合体への基質の徴集を容易にする.
- この相互作用を阻害したり,ニカストリンエクトドメインを変異させたりすると,基質結合と分裂が減少します.
結論:
- ニカストリンは,エクトドメインの脱落後のタイプI型トランスメブランタンパク質のアミノ端末ストブの受容体として機能する.
- ニカストリンはこれらの基質をガンマ分泌酵素に提示し,その膜内タンパク質分解を促進します.
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