バクテリアのフラゲリンとIII型分泌装置のためのNLRC4炎症体受容体
Yue Zhao1, Jieling Yang, Jianjin Shi
1Graduate Program in Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, China.
Nature
|September 16, 2011
まとめ
NAIPタンパク質は,バクテリアのフラゲリンとIII型分泌システム成分のための炎症センサとして作用し,重要な先天性免疫応答を活性化します. この発見は,微生物感染症に対するNLRC4炎症ゾームの活性化メカニズムを明確にします.
科学分野:
- 生まれながらの免疫力があります.
- 分子生物学と細胞生物学について
- 微生物学 微生物学とは
背景:
- インフラマソームは,微生物の脅威を感知し,炎症反応を開始するために重要です.
- NLRC4炎症ゾームは,細菌のフラゲリンとIII型分泌システム (TTSS) のコンポーネントを認識する.
- これらの刺激によってNLRC4炎症ゾームが活性化される正確なメカニズムは,依然としてほとんど不明です.
研究 の 目的:
- NLRC4炎症ゾームがバクテリアのフラゲリンとTTSS成分を検出する分子メカニズムを解明する.
- これらの細菌の毒性因子の認識に関与する特定の宿主タンパク質を特定する.
主な方法:
- NAIP-リガンド結合を研究するためのタンパク質相互作用アッセイ.
- 非マクロファージ細胞における炎症体複合体の再構成.
- マクロファージにおける細菌感染症の遺伝子分析.
主要な成果:
- NAIP5は細菌のフラゲリンに直接結合し,NLRC4炎症ゾームの活性化を媒介する.
- NAIP2は,TTSS棒タンパク質の特定の受容体として作用する.
- 人間のNAIPは,TTSS針のタンパク質CprIを認識し,NLRC4炎症体を活性化します.
結論:
- NAIPタンパク質は,バクテリアのフラゲリンとTTSS装置の部品のための不可欠な炎症体受容体である.
- これは,様々な細菌の病原体によるNLRC4炎症体の活性化のための保存されたメカニズムを特定します.
- NAIPファミリーの他のメンバーに関するさらなる研究は,新しい先天性免疫経路を明らかにする可能性があります.
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