エンドプラズマ網膜PI(3) Pの脂質結合は,マラリアタンパク質を宿主細胞に標的とする
Souvik Bhattacharjee1, Robert V Stahelin, Kaye D Speicher
1Center for Rare and Neglected Diseases, University of Notre Dame, Notre Dame, IN 46556, USA.
Cell
|January 24, 2012
まとめ
マラリア寄生虫プラズモディウムファルシパラムは,宿主標的 (HT) 信号を使用してタンパク質を輸出する. この信号は,プロテアゼ分裂とは無関係に,エンドプラズマ網膜内のフォスファティディル・イノシトール-3-フォスファート (PI(3) Pによって認識され,新しい分泌経路を明らかにします.
科学分野:
- * 分子生物学について
- * 寄生虫学について
- * 細胞生物学 細胞生物学
背景:
- * マラリア寄生虫プラズモディアム・ファルシパラムは,宿主標的 (HT) 信号を介して何百ものエフェクタータンパク質を輸出する.
- * 以前に,輸出はERプロテアゼ,プラズメプシンVによる割れにのみ依存すると考えられていた.
- *Plasmodium falciparumの分泌を理解することは,新しい抗マラリア戦略の開発に不可欠です.
研究 の 目的:
- *Plasmodium falciparumのHT信号媒介タンパク質輸出のメカニズムを調査する.
- * タンパク質分泌におけるフォスファディチルイノシトール-3-フォスファート (PI(3) P) の役割を決定する.
- * この輸出メカニズムの保存を他の病原体で探求する.
主な方法:
- *フォスファディチルイノシトール-3-フォスファート (PI(3) P) に結合するHT信号の分析.
- * 寄生虫内プラズマ網膜 (ER) 内のPI(3) PおよびHT信号を視覚化するための顕微鏡.
- *Plasmodium falciparumと病原性オオミケテにおけるHT信号輸出の比較分析.
主要な成果:
- *HT信号は,プラズメプシンV分裂とは無関係に,高い親和性を持つPI(3) Pを直接結合する.
- * PI(3) ERのP濃縮地域は,輸出先駆体に関するHT信号でコロカライズする.
- *PI(3) P依存のエクスポートは,プラズメプシンVがなくても,関連する病原性オオミケートに保存されます.
結論:
- * ERにおけるフォスファディチルイノシトール-3-フォスファート (PI(3) Pは,HT信号主導のタンパク質輸出の主要な媒介物である.
- *このPI(3) P認識メカニズムは,プロテアゼの作用に先行し,それとは独立しています.
- *この発見は,Plasmodium falciparumや他の生物の病原性にとって重要な保存された分泌経路を明らかにしています.
さらに関連する動画
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