E3リガゼRAD18は,IFNB1転写を終了するために,リン酸化IRF3を標的とする
Yiting Cai1,2, Jiaqi Zheng1,3, Linlin Zhao1,4
1Institute of Immunology, Zhejiang University School of Medicine, Hangzhou, China.
Nature immunology
|August 29, 2025
まとめ
RAD18は,リン酸化されたIRF3を分解し,タイプIインターフェロンの生成を停止します. この発見はウイルスの感染や自己免疫疾患の 治療対象となる可能性がある.
科学分野:
- 免疫学
- 分子生物学
- ウイルス学
背景:
- インターフェロン調節因子3 (IRF3) は,病原体に対する宿主防御に不可欠なタイプIインターフェロン転写の開始に不可欠です.
- インターフェロン経路の調節不良は,ウイルス感染症や全身性赤血性狼のような自己免疫疾患に関与しています.
研究 の 目的:
- IRF3駆動のインターフェロン転写の終結を調節する分子機構を特定する.
- リン酸化IRF3 (p-IRF3) の分解におけるRAD18の役割とその宿主防御への影響を調査する.
主な方法:
- RAD18とp- IRF3の相互作用を決定するための生化学的測定.
- ユビキティレーション検査は,ユビキティレーションの種類と特定のライシン残基を特定するために行われます.
- ウイルス感染に対する耐性を評価するために,遺伝子組み換えマウス (Rad18fl/fl Lysm-cre) を用いたin vivo試験.
- 活発な全身性狼およびH1N1感染の患者のヒトマクロファージおよびモノサイトにおけるRAD18,p- IRF3,およびIFNB1mRNAレベルの分析.
主要な成果:
- RAD18は選択的にp- IRF3をオートファージ分解するE3ユビキチンリガゼとして特定されました.
- RAD18は,Lys193でK63のポリユビキチル化を誘発することによって,IFNBプロモーターからp- IRF3の解離を促進する.
- ユビキタイルされたp- IRF3はプロモーターから離散し,核の外に転移し,分解される.
- Rad18fl/fl Lysm-creのマウスは,IFNβの生成が増加したため,致命的な膀性口炎ウイルス感染に対する耐性を示した.
- 人間のサンプルでは,H1N1に感染したマクロファージ/単細胞および活発な全身性白血球性狼を有する個体において,RAD18タンパク質レベルはp- IRF3およびIFNB1のmRNAレベルと負の相関性を示した.
結論:
- RAD18は,IRF3媒介のIFNB1転写を終了するネガティブレギュラーとして作用する.
- RAD18によるp- IRF3の分解は,インターフェロン反応における重要なチェックポイントである.
- RAD18は,異常なインターフェロンシグナル伝達によって特徴づけられるRNAウイルス感染症と自己免疫疾患の管理のための潜在的な治療標的を表しています.
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