化学反応信号経路の出力における適応

Junhua Yuan¹, Richard W Branch, Basarab G Hosu

¹Department of Molecular and Cellular Biology, Harvard University, Cambridge, Massachusetts 02138, USA.

Nature

|April 14, 2012

まとめ

バクテリアモーターは,その組成,特にFliMサブユニットの数を変更することによって,変化する条件に適応します. この適応的改造は,受容体入力と運動感受性のマッチを最適化し,細胞機能を強化します.

科学分野:

バクテリアの化学作用と分子機構.
細胞の信号伝達と適応メカニズム.

背景:

バクテリアの化学作用は,受容体クラスターが入力処理し,フラジェラモーターが CheY-P と結合して出力を生成することに依存しています.
CheY-P濃度に対するモーターの超敏感性は,受容体の出力とモーターの入力とのマッチングに課題を提示します.

研究の目的:

バクテリアモーターが受容体の出力とモーターの入力とのマッチングをどのように最適化するかを調査する.
モーターが動作範囲を変化させるメカニズムを探求する.

主な方法:

感受体および運動複合体を含むバクテリアの化学作用ネットワークの構成要素の分析.
CリングにおけるFliMサブユニットの役割と,CheY-P濃度変化に対するそれらの反応を調査する.

主要な成果:

バクテリアモーターは,その組成を変化させ,特に,減少したCheY-Pに反応してFliMサブユニットを増加させることで,その動作範囲を変化させることができます.
この組成の変化は,運動感受性を高め,特定の変異体における適応と,信号に依存するFliMの周回を説明する.

結論:

FliMサブユニット番号などのモーター組成の適応的な改造は,細胞応答を最適化するための重要なメカニズムです.
この適応的戦略は,多様な分子機械の動作における共通の特徴である可能性が高い.

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