トライパノソームの細胞表面の水力動的流れ媒介型タンパク質分類
Markus Engstler1, Thomas Pfohl, Stephan Herminghaus
1Institut für Mikrobiologie und Genetik, Technische Universität Darmstadt, Schnittspahnstrasse 10, 64287, Darmstadt, Germany. engstler@bio.tu-darmstadt.de
Cell
|November 6, 2007
まとめ
トリパノソーマブルセイは,細胞にIg-VSG複合体を移動させ,宿主免疫グロブリン (Ig) を除去する.
科学分野:
- 寄生虫学とは,寄生虫学である.
- 細胞生物学 細胞生物学
- 免疫学 免疫学とは
背景:
- 単細胞の寄生虫トライパノソーマ・ブルセイは,表面のタンパク質を急速に流すことで宿主の免疫を回避する.
- 変異的表面グリコタンパク質 (VSG) は,寄生虫の表面を覆い,グリコシルフォスファティディルニノシトール (GPI) を固定します.
- VSGに結合する宿主由来免疫グロブリン (Ig) は,寄生虫の生存に課題をもたらします.
研究 の 目的:
- トライパノソーマ・ブルセイが宿主免疫グロブリン (Ig) を表面から除去するメカニズムを解明する.
- Ig-VSG免疫複合体の除去における細胞運動性とエンドサイトーシスの役割を調査する.
- このクリアランスメカニズムが寄生虫の生存と他の細胞タイプにおける潜在的な役割に及ぼす影響を理解する.
主な方法:
- 寄生虫の表面でのIg-VSG免疫複合体の動きを観察する.
- 免疫複合体の動きが細胞の運動性,内細胞性,アクチン機能に依存していることの分析.
- タンパク質の分類における水力力学的力の役割を調査する.
主要な成果:
- Ig-VSG免疫複合体は,Trypanosoma brucei.の後部細胞極に受動的にソートされます.
- この動きは前向きの細胞運動を必要とするが,エンドサイトーシスとアクチンとは独立している.
- 泳ぐトライパノソームに作用する水力動力学的流れは,分子帆として機能するIg-VSG複合体の方向運動を駆動します.
結論:
- トリパノソーマ・ブルセイは,抗体のクリアランスのユニークなメカニズムを採用し,Ig-VSG免疫複合体の方向的な動きのために,水力力学的な力を利用します.
- このメカニズムは,トリパノソームを補足媒介による破壊から保護するのに役立ちます.
- この発見は,上皮細胞などの他の細胞タイプにおける水力動的タンパク質分類の潜在的機能的重要性を示唆しています.
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