JAK-STAT信号伝達のキナーゼ独立小分子阻害
Danny Hung-Chieh Chou1, Amedeo Vetere, Amit Choudhary2
1‡Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, United States.
Journal of the American Chemical Society
|June 5, 2015
まとめ
小分子BRD0476は,USP9X経由でJAK-STAT経路を抑制することによって,臓細胞を保護する. これは,USP9Xが炎症を調節する新しい標的であることを明らかにします.
科学分野:
- 細胞生物学 細胞生物学
- 分子生物学は分子生物学である.
- 薬理学 薬理学とは
背景:
- 薬剤発見にはフェノタイプのスクリーニングが不可欠ですが,ヒットの分子標的と作用機構 (MoA) を特定することは依然として困難です.
- 臓のβ細胞アポトーシスは糖尿病の重要な要因であり,その調節を理解することは,治療の開発に不可欠です.
研究 の 目的:
- 小分子BRD0476の細胞内標的とMoAを明らかにし,臓β細胞アポトーシスの新しい抑制剤である.
- ジャヌスキナーゼ2 (JAK2) と信号トランスデューサー,およびトランスクリプション1 (STAT1) 信号伝達経路の活性化に対する化合物の効果を調査する.
主な方法:
- ネズミのベータ細胞における定量タンパク質分析により,BRD0476.6の細胞内標的を特定する.
- RNA干渉 (RNAi) とCRISPR/Cas9遺伝子編集により,標的を検証する.
- 特定された標的の既知の阻害剤を使用した逆化学遺伝学.
- サイト・ディレクテッド・ミュータゲネシスで,リン酸化とユビキチネーションの相互作用を調査する.
主要な成果:
- BRD0476は,インターフェロン-ガンマ (IFN-γ) 誘発のJAK2/STAT1シグナリングを阻害し,JAKキナーゼ活性を抑制することなくベータ細胞の生存を促進します.
- 定量プロテオミクスは,ユビキチン特異ペプチダゼ9X (USP9X) を細胞内標的として特定した.
- USP9XのノックダウンとUSP9Xの阻害はBRD0476の効果を模倣した.
- ミュタゲネーシスは,BRD0476のMoAは,JAK2のリン酸化とユビキチネーションの競争を伴うことを示唆した.
結論:
- フェノタイプのスクリーニングとMoAの研究は,確立されたシグナル伝達経路に関する新しい洞察を生み出します.
- USP9Xは,細胞炎症におけるJAK2活性を調節し,ベータ細胞の生存を促進する潜在的な治療標的として特定されています.
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