バクテリアの滑り動く運動性タンパク質の極から極への調節された振動
Tâm Mignot1, John P Merlie, David R Zusman
1University of California, Department of Molecular and Cell Biology, Berkeley, CA 94720-3204, USA.
Science (New York, N.Y.)
|November 8, 2005
まとめ
Myxococcus xanthusバクテリアは,IV型 pili. を使用して方向を逆転させます. FrzSと呼ばれるタンパク質は,Frzシステムによって調節され,細胞の極の間で振動し,誘導運動性を制御します.
科学分野:
- 微生物学 微生物学とは
- バクテリアの移動性
- 細胞生物学 細胞生物学
背景:
- 導かれた細菌の運動性は,生存とコロニー形成に不可欠である.
- タイプIVの piliは,細菌の移動のための重要なメカニズムであるの運動を媒介する.
- 誘導運動期間の細胞極性の調節は,まだ十分に理解されていない.
研究 の 目的:
- Myxococcus xanthus.の誘導運動性の基礎にある分子機構を調査する.
- 細胞の極性を調節する Frz 化学感知システムの役割を明らかにする.
- 誘導運動に関与するタンパク質のダイナミクスを理解する.
主な方法:
- Myxococcus xanthus.の生細胞画像を撮ったものです.
- 細胞の逆転時にタイプIV piliダイナミクスの追跡.
- FrzSタンパク質の細胞下部位と移動をモニタリングする.
主要な成果:
- タイプIV piliは,一つの極で解体し,細胞の逆転時に反対の極で再構成します.
- タンパク質FrzSは,細胞の逆転と同期した振動的な極から極への移動を示しています.
- Frz 化学センサーシステムは,FrzS 振動の周波数と,誘導された運動性を制御します.
結論:
- FrzSのダイナミクスと極から極への移動は,Myxococcus xanthus.の細胞の極性を調節するために重要である.
- Frz化学感知系は,FrzSの振動を制御することによって,指向運動性のマスターレギュレータとして機能します.
- この研究は,細菌の誘導運動のためのピリダイナミクスの調整とタンパク質の局所化の調整に関する新しい洞察を提供します.
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