ROSに依存するS-パルミトイライション活性化剤は,割れ,無傷のガスダーミンD
Gang Du1,2, Liam B Healy3,4, Liron David5,6,7
1Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA, USA. gdu@crystal.harvard.edu.
Nature
|April 10, 2024
まとめ
ガスダーミンD (GSDMD) はパルミトイロ化されていて,これは熱死時に毛穴形成に不可欠な変化です. この可逆パルミトイレーションは,GSDMDの活性化に重要なスイッチとして作用し,分裂が唯一のトリガーであるという以前の概念に異議を唱えます.
科学分野:
- 細胞生物学
- 免疫学
- 生物化学
背景:
- ガスダーミンD (GSDMD) は炎症体の活性化における重要なエフェクタであり,トランスメブランの毛穴を形成することによって,サイトカインの分泌と発火を媒介する.
- GSDMDの毛孔形成は,主にカスパース分裂によって生成されるN端領域 (GSDMD-NT) に起因している.
研究 の 目的:
- GSDMDの活性化における 分割を超えた翻訳後の改変の役割を調査する.
- GSDMD媒介による熱死を制御する新しい規制メカニズムを特定する.
主な方法:
- 生物化学的測定を用いてCys191におけるGSDMDのパルミトイレーションの評価
- S-パルミトイライションがGSDMDの孔形成とピロプトーシスに与える影響を,割れ欠の変異体とリポソーム漏れ試験を用いて調べる.
- GSDMDパルミトイルトランスフェラーゼ (ZDHHC5,ZDHHC9) を特定し,炎症体活性化と活性酸素種 (ROS) によってその調節を分析する.
主要な成果:
- GSDMD Cys191はS-palmitoylatedであり,この改変はカスパースの割れ分から独立して毛穴形成に不可欠である.
- ミトコンドリア由来反応性酸素種 (ROS) は,GSDMDのパルミトイロ化を強化する.
- パルミトイロ化されたGSDMDは,割れが欠けている形態を含む,リポソームの漏れとピロプトーシスを誘発し,パルミトイロ化がガスダーミン族の重要な活性化スイッチとして作用する.
結論:
- リバーシブルS-パルミトイライションはガスダーミンDの孔形成と熱死に対する重要なチェックポイントであり,ガスダーミンファミリーの一般的なアクティベーションスイッチとして機能する.
- この発見は,GSDMDの活性化にカスパース媒介の分裂が唯一のトリガーであるというパラダイムに挑戦しています.
- パルミトイレーションは,炎症反応を調節するための新しい治療目標です.
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