炎症ゾームの活性化とHMGB1の放出におけるPKRの新たな役割
Ben Lu1, Takahisa Nakamura, Karen Inouye
1Laboratory of Biomedical Science, The Feinstein Institute for Medical Research, 350 Community Drive, Manhasset, New York 11030, USA. blu@nshs.edu
Nature
|July 18, 2012
まとめ
双鎖RNA依存タンパク質キナーゼ (PKR) は,炎症体の活性化に不可欠です. PKRを阻害することは,サイトカインの放出を阻害することによって,潜在的に炎症性疾患を治療することができます.
科学分野:
- 免疫学 免疫学とは
- 分子生物学は分子生物学である.
- セルラー・シグナリング
背景:
- 炎症体複合体は,IL-1β,IL-18およびHMGB1.1を含む主要な炎症性サイトカインの放出をオーケストラします.
- 炎症体活性化を調節するメカニズムの理解は,標的型抗炎症療法の開発に不可欠です.
研究 の 目的:
- 炎症体の活性化における二重鎖RNA依存タンパク質キナーゼ (PKR,EIF2AK2とも呼ばれる) の役割を調査する.
- PKRが炎症体シグナル伝達に影響を与える分子メカニズムを解明する.
主な方法:
- 様々な炎症性アゴニストによるマクロファージ刺激.
- 遺伝子削除とPKRの薬理学的阻害.
- サイトカインの放出 (IL-1β,IL-18,HMGB1) の評価
- コイムノプレシピテーションアッセイは,タンパク質の相互作用を研究するためのものです.
- 再結合タンパク質を用いた炎症体の活性を in vitro で再構成する.
主要な成果:
- PKR自己リン酸化は,炎症性アゴニストへの曝露時に誘発された.
- PKRの欠乏または抑制は,細菌およびウイルス成分,ATP,結晶物質を含むさまざまな刺激において,炎症体の活性化を著しく低下させた.
- PKRは,複数の炎症ゾーム成分 (NLRP3,NLRP1,NLRC4,AIM2) と物理的に相互作用する.
- 細胞のないシステムでPKR,NLRP3,ASC,およびプロカスペーゼ-1を用いて炎症体の活性を再構成した.
結論:
- PKRは,炎症体の活性化を調節する上で重要かつ広範な役割を果たします.
- PKRは,炎症状態の管理のための潜在的な治療目標を表しています.
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