活性細胞骨格ネットワークの非均衡メカニズム

Daisuke Mizuno¹, Catherine Tardin, C F Schmidt

¹Department of Physics and Astronomy, Vrije Universiteit, 1081HV Amsterdam, Netherlands.

Science (New York, N.Y.)

|January 20, 2007

まとめ

細胞の力は,複雑なネットワークである細胞骨格によって生成されます. ミオシンIIやアクチンフィラメントのようなモータータンパク質は,細胞骨格の硬さを劇的に増加させ,その機械的性質を変化させます.

科学分野:

バイオフィジックス生物物理学
細胞生物学細胞生物学
ソフトマター物理学ソフトマター物理学

背景:

細胞骨格 (cytoskeleton) は,力学的な整合性と力生成を担うダイナミックな細胞構造である.
細胞骨格ネットワークの活性メカニズムを理解することは,細胞の運動性と機能にとって極めて重要です.

研究の目的:

ミニマルの細胞骨格モデルで運動活動と機械的性質の関係を調査する.
ミオシンIIの運動活動がアクチンネットワークのダイナミクスと粘性弾力性にどのように影響するかを定量化するために.

主な方法:

3つの構成要素のシステム (アクチン,ミオシンII,クロスリンカー) の動力学および機械的性質の実験的測定.
定量的理論モデルを使用して,分子力生成をマクロスケープのネットワーク行動と関連付けました.

主要な成果:

モーターによって引き起こされるストレスは,ネットワークの硬さを100倍近く大幅に増加させました.
活性ゲルの粘着弾性反応は,アデノシン三酸塩に依存した方法で質的に変化した.
分子レベルの力生成を大規模の活性ゲル特性と接続するためのモデルが開発されました.

結論:

ミオシンIIモーターによるアクティブフォース生成は,細胞骨格力学の重要な決定因子です.
この研究は,生物学的システムにおける活性物質を理解するための定量的な枠組みを提供します.
発見は,細胞の機械的行動を支配する物理的原理の洞察を提供します.

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