アダプタタンパク質3によるトール型受容体9のシグナリングの分岐
Miwa Sasai1, Melissa M Linehan, Akiko Iwasaki
1Department of Immunobiology, Yale University School of Medicine, New Haven, CT 06520, USA.
まとめ
トール型受容体9 (TLR9) のシグナリングは,特化したエンドソームへの密輸によって二分される. アダプタータンパク質-3はTLR9の動きを媒介し,選択的にタイプIインターフェロンを活性化するが,炎症誘発性サイトカインは活性化しない.
科学分野:
- 免疫学 免疫学とは
- 細胞生物学 細胞生物学
- 分子生物学は分子生物学である.
背景:
- 内体型トール型受容体 (TLRs) 7と9は,ウイルス核酸の認識に不可欠である.
- TLRの活性化はシグナリングカスケードを誘発し,炎症誘発性サイトカインとI型インターフェロン (IFN) の生成につながります.
- TLR9は,ウイルスの核酸の認識のために,エンドソーム分裂を必要とします.
研究 の 目的:
- TLR9信号のバイフォーケーションを制御する細胞内メカニズムを調査する.
- 微分TLR9シグナル伝達における受容体トラフィックの役割を決定する.
- TLR9の局所化と機能に関与するタンパク質を特定する.
主な方法:
- TLR9信号伝達経路の分析.
- 顕微鏡と細胞分断を用いたTLR9の密輸の調査.
- 相互作用するタンパク質の識別は,共免疫プレシピテーションと質量スペクトロメトリーにより行われます.
主要な成果:
- TLR9がエンドソームからリソソームに関連する特殊な臓器細胞に密輸することは,タイプIのIFN活性化には不可欠ですが,炎症性サイトカイン誘導には必要ありません.
- アダプタータンパク質-3 (AP-3) 複合体は,TLR9をこの特定のサブセルラー部位に密輸することを媒介する.
- このトラフィッキングメカニズムは,TLR9.9の下流で異なるシグナリング結果の選択的活性化を可能にします.
結論:
- エンドソーム系内の選択的受容体取引は,TLR9信号を二分する細胞内メカニズムを提供します.
- アダプタータンパク質-3は,TLR9をタイプIIFNの産生を促進するコンパートメントに誘導する上で重要な役割を果たします.
- この経路を理解することで,ウイルス病原体に対する先天的な免疫反応の調節に関する洞察が得られます.
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