ライソソーマルラグ・レギュレータ・コンプレックスは,YersiniaによるRIPK1およびカスパース-8媒介型熱死を引き起こす
Zengzhang Zheng1,2, Wanyan Deng1,2, Yang Bai2,3
1The Joint Center for Infection and Immunity between Guangzhou Institute of Pediatrics, Guangzhou Women and Children's Medical Center (Guangzhou, 510623, China) and Institut Pasteur of Shanghai, Chinese Academy of Sciences, Shanghai, 200031, China.
まとめ
病原性Yersinia感染は炎症性細胞死の一種であるピロプトーシスを引き起こす. 研究者らは,リゾソームのRag-Ragulator複合体が,mTORC1のシグナル伝達から独立して,意外にこの反応を媒介することを発見した.
科学分野:
- 細胞生物学
- 免疫学
- 微生物学
背景:
- 宿主細胞は 病原体の侵入と戦うために 細胞死経路を利用します
- 病原性YersiniaはマクロファージのTAK1を阻害し,カスパース-8とGSDMD分裂によるRIPK1依存性熱死を引き起こす.
研究 の 目的:
- イエルシニア感染時のカスパーゼ8依存型熱中症の新たな媒介者を特定する.
- リンソームのFLCN-FNIP2-Rag-Ragulator複合体のYersinia誘発性炎症性細胞死における役割を明らかにする.
主な方法:
- ピロプトーシスを調節する遺伝子を特定するための全ゲノムCRISPRスクリーンです.
- タンパク質複合体の形成を研究する共免疫降水測定法.
- Rag-RagulatorのGTPase活性とリソソームの局所化の分析
主要な成果:
- CRISPRスクリーンは,溶解体FLCN-FNIP2-Rag-Ragulator超複合体を,熱死症の重要な調節体として明らかにした.
- FADD,RIPK1,カスパース-8はYersinia感染時にRag-Ragulator複合体に採用されました.
- RIPK1のリン酸化とカスパース8の活性化は,Rag GTPaseの活性とRag-Ragulatorのリソソーム結合に依存しているが,mTORC1のシグナル伝達には依存していない.
結論:
- 溶解体Rag-Ragulator複合体は,Yersiniaが誘発する熱死症の予期せぬ媒介体である.
- Rag-Ragulatorはシグナルハブとして機能し,Yersinia感染に対する炎症反応を指示します.
- この発見は,リゾソームの代謝シグナル伝達と先天的な免疫反応の間の新しいリンクを明らかにしています.
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