FK506結合タンパク質によるカルシウム放出チャネル (リアノジン受容体) 機能の安定化
A B Brillantes1, K Ondrias, A Scott
1Department of Medicine, Mount Sinai School of Medicine, New York, New York 10029.
Cell
|May 20, 1994
まとめ
FK506結合タンパク質 (FKBP12) は,リアノジン受容体 (RyR) の機能に不可欠であり,カルシウム放出チャネルを調節します. この研究は,FKBP12を明らかにしています.
科学分野:
- 分子生物学は分子生物学である.
- 細胞生理学 細胞生理学
- バイオケミストリー バイオケミストリー
背景:
- FKBP12は,広く発現するプロリンイソメラーゼである.
- その細胞機能は,この研究の前にほとんど知られていなかった.
- FKBP12は,ライオノジン受容体 (RyR) と相互作用することが知られている.
研究 の 目的:
- FKBP12.2の細胞機能を解明する.
- RyRチャネル活動の調節におけるFKBP12の役割を決定する.
- 細胞内カルシウム放出に対するFKBP12の影響を調査する.
主な方法:
- 昆虫の細胞におけるRyRとFKBP12の共発.
- RyRチャネルゲーティング特性の分析.
- FKBP12イソメラーゼ活性に関する評価は,FK506とラパミシンを用いて行われました.
主要な成果:
- FKBP12は,完全な導電性を持つ RyR チャンネルの数を大幅に増加させます.
- FKBP12は,カフェインの活性化後にRyRチャネルが開く確率を低下させます.
- FKBP12は,RyRチャネルの平均開き時間を増加させます.
- 阻害剤FK506とラパミシンは,RyRチャネルに対するFKBP12の安定効果を逆転させた.
結論:
- この研究は,FKBP12.2に対する最初の自然な細胞機能を確立した.
- FKBP12は,ライオノジン受容体チャネルゲーティングの重要な調節剤として作用します.
- 機能的なCa2+放出チャネル複合体は,本質的にFKBP12.2を含む.
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