ポリペプチドは,JakおよびStatタンパク質のチロシンリン酸化によって核にシグナルを送る
K Shuai1, A Ziemiecki, A F Wilks
1Laboratory of Molecular Cell Biology, Rockefeller University, New York 10021-6399.
Nature
|December 9, 1993
まとめ
インターフェロン (IFN) は,シグナルトランスデューサーとトランスクリプション (Stat) タンパク質のアクティベーションをチロシンリン酸化経由でトリガーします. この研究では,ジャヌスキナーゼ1 (Jak1) がIFNとEGFに対する反応としてStat91をリン酸化する重要な酵素である可能性があることが示唆されています.
科学分野:
- 細胞の信号伝達経路は,
- 分子生物学は分子生物学である.
- 免疫学 免疫学とは
背景:
- インターフェロン (IFN) は細胞表面受容体に結合し,信号伝導を開始します.
- 信号トランスデューサーと転写 (Stat) タンパク質のアクティベーターのチロシンリン酸化は,重要な早期イベントです.
- 特定のチロシンキナーゼ,チロシンキナーゼ-2 (Tyk2) とジャヌスキナーゼ2 (Jak2) は,それぞれIFN-αとIFN-gammaシグナル伝達に関与しています.
研究 の 目的:
- StatおよびJakタンパク質のチロシンリン酸化イベントを調査する.
- インターフェロンと表皮成長因子 (EGF) のシグナル伝達経路における特定のキナーゼの役割を決定する.
主な方法:
- IFN-アルファ,IFN-ガンマ,EGFによる細胞治療.
- StatおよびJakタンパク質におけるチロシンリン酸化の分析.
- 異なるリガンドによるキナーゼ活性化の比較.
主要な成果:
- Stat91はTyr701上でIFN-α,IFN-gamma,EGFによってリン酸化される.
- ジャヌスキナーゼ1 (Jak1) は,3つのリガンドすべてによって酸化されたチロシンです.
- 各リガンドは少なくとも1つの異なるキナーゼを活性化します.
結論:
- Jak1は,Stat91.1.でTyr701をリン酸化するための潜在的な候補酵素である.
- Jak1は,IFNとEGFによって活性化されたシグナル伝達経路に役割を果たしています.
- インターフェロンと成長因子のシグナル伝達経路は,共通の成分とメカニズムを共有しています.
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