転写因子c-Junを調節するストレス活性化経路におけるSAPK/ERKキナーゼ-1の役割
I Sánchez1, R T Hughes, B J Mayer
1Diabetes Research Laboratory, Massachusetts General Hospital East, Charlestown.
Nature
|December 22, 1994
まとめ
ストレス活性化タンパク質キナーゼ (SAPK) は,細胞のストレス反応に不可欠です. この研究は,SAPK/ERK キナーゼ-1 (SEK1) を新しい上流活性化剤として特定し,ストレスから遺伝子活性化までの重要なシグナル伝達経路を定義しています.
科学分野:
- セルラー・シグナリング
- 分子生物学は分子生物学である.
- ストレス反応経路 ストレス反応経路
背景:
- ストレス活性化タンパク質キナーゼ (SAPKs) は,様々なストレスに対する細胞反応の重要な調節体です.
- SAPKはミトゲン活性化タンパク質キナーゼ (MAPK) とは異なるが,関連するシグナリングカスケードを共有している.
- c-JunのSAPK活性化は,遺伝子転写の調節に関与しています.
研究 の 目的:
- SAPKの活性化に関与する新しいタンパク質キナーゼを特定する.
- 新しく特定されたキナーゼ,SAPK/ERKキナーゼ-1 (SEK1) のストレスシグナル伝達における役割を特徴付ける.
- 細胞のストレスとc-Jun転写因子を結びつけるシグナリングカスケードの解明.
主な方法:
- 新しいタンパク質キナーゼの識別と特徴付け,SEK1.
- SEK1によるSAPKsの活性化を評価するためのin vitroおよびin vivoアッセイ.
- 不活性なSEK1変異体を使って,SAPKの活性化阻害におけるその役割を調査した.
主要な成果:
- SEK1は,構造的にMAPキナーゼキナーゼ (MEKs) に関連する新しいタンパク質キナーゼとして特定されました.
- SEK1は,SAPKsの強力な活性化をインビトロおよびインビボの両方で実証しました.
- 不活性なSEK1変異体は,MAPK経路に影響を与えることなく,細胞外刺激によって誘発されたSAPK活性化を効果的に阻害しました.
結論:
- SEK1はSAPKの重要なアップストリームアクティベーターであり,重要なシグナル伝達経路を定義します.
- この経路は,細胞のストレス信号をc-Jun転写因子の活性化と結びつけます.
- SEK1は,ストレス誘発のシグナリングカスケードに新しい分子リンクを提供する.
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