収縮環の構造記憶は,細胞の大きさに依存しないサイトキネーシスの持続を可能にします

Ana Carvalho¹, Arshad Desai, Karen Oegema

¹Ludwig Institute for Cancer Research, Department of Cellular and Molecular Medicine, University of California, San Diego, CMM-East 3080, 9500 Gilman Drive, La Jolla, CA 92093, USA. ancarvalho@ucsd.edu

Cell

|June 4, 2009

まとめ

C. elegansのサイトキネシスには,2段階のリング収縮が伴う. リングリング

科学分野:

細胞生物学細胞生物学
発達生物学発達生物学とは
バイオフィジックス生物物理学

背景:

細胞分裂のプロセスであるサイトキネシスは,皮質の収縮環の収縮に依存しています.
収縮環の解離のメカニズムを理解することは,細胞分裂を理解するために不可欠です.

研究の目的:

C. elegans.の初期胚分裂中の収縮環収縮の動態を調査する.
リング収縮の速度とその細胞サイズとの関係に関するメカニズムを解明する.

主な方法:

C. elegans の胚の光で標識された収縮輪の生画像.
リング収縮率とミオシン動態の定量分析.

主要な成果:

収縮指輪の収縮は2つの段階で行われる:恒定速度の段階に続いて,指輪周長に比例する減速段階.
細胞分裂の持続期間は,細胞サイズが減少しているにもかかわらず,初期リングサイズと収縮率の間の比例性のために,細胞分裂の間で一定です.
ミオシンのレベルは,回転せずに閉じる際にリングの周長に比例して低下し",収縮性ユニット"モデルを示唆します.

結論:

"収縮ユニット"モデルは,解体中にリングがサイズメモリを維持する方法を説明しています.
リング収縮のスケーラブルな性質は,異なる細胞サイズで細胞分裂イベントの調整を容易にする.

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