成長するマイクロチューブルのための力-速度関係の測定

M Dogterom¹, B Yurke

¹Bell Laboratories, Lucent Technologies, 600 Mountain Avenue, Murray Hill, NJ 07974, USA.

Science (New York, N.Y.)

|November 5, 1997

まとめ

研究者は,細胞分裂中に単一のマイクロチューブルによって生成される力を測定した. 微小管の成長は,増加する力によって著しく減速し,予想よりも早く減少しました.

科学分野:

細胞生物学細胞生物学
バイオフィジックス生物物理学
細胞骨格ダイナミクス

背景:

タンパク質のポリメリゼーションは細胞の運動を駆動する.
マイクロチューブルはミトーシス中の染色体移動に不可欠です.
微小管の力を理解することは,細胞力学の鍵です.

研究の目的:

単一のマイクロチューブルが及ぼす力を定量化するために.
マイクロチューブルの力と成長速度との関係を決定する.
実験結果と微小管動力の理論モデルを比較する.

主な方法:

マイクロチューブルは,片端に基板に固定されていました.
マイクロチューブルは,マイクロファブリック製の硬い障壁に押し付けられています.
微小管の屈折を分析して,力と成長速度を測定した.

主要な成果:

微小管の成長速度は,ゼロフォースでの1.2μm/minから,午後3〜4時に0.2μm/minに減少した.
力と速度の関係は,指数関数的に衰えるパターンをたどった.
観測された力-速度衰退の速度は,理論的な予測よりも速かった.

結論:

微小管の力発生は,成長速度に大きな影響を与えます.
実験結果は,既存の理論的モデルと一致するが,それからは逸脱する.
マイクロチューブルポリメリゼーションの理論のさらなる精細化は正当化されています.

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