Saccharomyces cerevisiaeにおけるオスモ適応の周波数依存性について
Jerome T Mettetal1, Dale Muzzey, Carlos Gómez-Uribe
1Department of Physics, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
Science (New York, N.Y.)
|January 26, 2008
まとめ
イーストのオスモ適応は,Hog1キナーゼからの迅速な負のフィードバックに依存しています. ゆっくりとした遺伝子発現フィードバックは,細胞が将来のオスモティックショックにより迅速に適応するのを助けます.
科学分野:
- 細胞生物学 細胞生物学
- システム生物学 システム生物学
- バイオケミストリー バイオケミストリー
背景:
- シグナリングカスケードは,迅速なリガンド受容体結合から,ゆっくりとした遺伝子発現まで,多様な時間スケールを伴う.
- 細胞の反応における支配的動態を理解することは,細胞の行動を予測する上で極めて重要です.
研究 の 目的:
- イーストのオスモ適応経路における支配的な時間スケールを調査する.
- 信号伝達ダイナミクスを支配する重要な規制メカニズムを特定する.
主な方法:
- 信号伝導の周波数依存性を評価するために周期的刺激を利用した.
- オスモ適応経路の予測モデルを開発するために,システム識別技術を適用した.
主要な成果:
- オスモ適応反応は,主にHog1キナーゼを含む急速な負のフィードバックループによって制御されます.
- この迅速なフィードバックメカニズムは,タンパク質合成とは独立して動作する.
- 遺伝子発現によって媒介されるより遅いネガティブなフィードバックは,重要なオスモティックショックの後に出現します.
結論:
- Fast Hog1 キナーゼフィードバックは,酵母オスモ適応における支配的要因である.
- 遺伝子発現に基づくフィードバックは,その後のオスモス的な課題に対する適応的利点を提供します.
- 速くて遅いフィードバックの相互作用は,環境の変化に対する細胞の反応を最適化します.
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