ラパミシンは,p70 S6キナーゼのインターリューキン-2活性化を選択的に抑制する
C J Kuo1, J Chung, D F Fiorentino
1Howard Hughes Medical Institute, Unit in Molecular and Genetic Medicine, Beckman Center, Stanford University School of Medicine, California 94305-5425.
Nature
|July 2, 1992
まとめ
マクロリドラパミシンは,p70 S6キナーゼの活性化を阻害することによって,細胞サイクル進行を停止します. この発見は,T細胞の増殖と免疫抑制を調節する保存された経路を明らかにしています.
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:
- マクロリドであるラパミシンは,酵母と哺乳類の細胞の細胞サイクルを停止し,S相への入り口のための保存された規制経路を示唆しています.
- 哺乳類では,ラパミシンは,インターレウキン-2受容体誘発S相エントリーを遮断することにより,T細胞の増殖を抑制し,免疫抑制につながります.
研究 の 目的:
- ラパミシンがインタールイキン2誘発のT細胞増殖を抑制するメカニズムを調査する.
- T細胞におけるラパミシンがターゲットとする特定のシグナル伝達経路を特定する.
主な方法:
- インタレウキン-2がp70S6キナーゼ,MAPキナーゼ (ERK),S6キナーゼ (RSK) のリン酸化および活性化に及ぼす影響を調査した.
- インタールイキン-2誘発のp70 S6キナーゼ活性化に対するラパミシンの影響を評価した.
- ラパミシン,FK506,FKBPとの相互作用を調べました.
主要な成果:
- インターリューキン-2は選択的にp70 S6キナーゼのリン酸化と活性化を刺激しますが,ERKやRSKは刺激しません.
- ラパミシンは,低濃度 (0.05-0.2 nM) でインタールイキン-2誘発のp70 S6キナーゼ活性化を迅速かつ完全に抑制します.
- FK506は,ラパミシンの効果を競争的に対抗し,FKBPによるメディエーションを示しています.
結論:
- ラパミシン-FKBP複合体は,p70 S6キナーゼ活性化カスケードを選択的にブロックする.
- このシグナル伝達経路は,T細胞のS相への入り口の調節に関与しています.
- ラパミシンの免疫抑制効果は,p70 S6キナーゼシグナル伝達の抑制と関連しています.
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