アスパルチルプロテアゼは,マラリアエフェクタータンパク質を宿主細胞に誘導する
Justin A Boddey1, Anthony N Hodder, Svenja Günther
1The Walter and Eliza Hall Institute of Medical Research, Melbourne 3052, Australia.
Nature
|February 5, 2010
まとめ
マラリアの寄生虫であるプラズモディウム・ファルシパラムは,特定のモチーフを用いてタンパク質を輸出する. 研究者らは,プラズメプシンV (PMV) を,このモチーフの分裂に不可欠なプロテアゼとして特定し,寄生虫の生存を可能にし,新しい治療標的を提供しました.
科学分野:
- 分子寄生生物学は,分子寄生生物学である.
- 感染症 感染症は感染症です.
- エリトロサイト生物学 エリトロサイト生物学
背景:
- プラズモディウム・ファルシパラムは,感染した赤血球を改造することによって重度のマラリアを引き起こす.
- 寄生虫の生存は,エフェクタータンパク質を真空圏を超えて輸出することに依存しています.
- 輸出されたタンパク質は,未知のプロテアゼによって割れた保存されたペンタメリクモチーフ (RxLxE/Q/D) を共有しています.
研究 の 目的:
- Plasmodium falciparumのペンタメリク出口モチーフを分裂させるプロテアゼを特定する.
- このプロテアゼが赤血球の改造と寄生虫の毒性における役割を明らかにする.
主な方法:
- プロテアゼの活性性を特定するための生化学的測定法.
- プラズモディアム・ファルシパラムの遺伝子操作.
- タンパク質の輸出とNターミナル加工の分析.
主要な成果:
- プラズメプシンV (PMV) は,ER-レジデントアスパルティックプロテアゼであり,責任あるプロテアゼとして特定されました.
- PMVはRxLxE/Q/Dモチーフを分割し,N端の輸出信号 (xE/Q/D) を明らかにする.
- PMVの活動は,タンパク質の輸出に不可欠であり,シグナルペプチダース処理とは異なり,他の重要な輸出イベントに関連しています.
結論:
- プラズメプシンVは,Plasmodium falciparumのエフェクタータンパク質を赤血球に輸出するために不可欠です.
- PMV媒介による分裂は,寄生虫の毒性にとって重要なステップです.
- PMVは,マラリア治療の新たな治療目標です.
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Eukaryotic cells can degrade proteins through several pathways. One of the most important among these is the ubiquitin-proteasome pathway. It helps the cell eliminate the misfolded, damaged, or unwarranted cytoplasmic proteins in a highly specific manner.
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