核包膜タンパク質の線形配列は,核の動きのために逆行性アクチン流を活用する

G W Gant Luxton¹, Edgar R Gomes, Eric S Folker

¹Department of Pathology and Cell Biology, Columbia University, New York, NY 10032, USA.

Science (New York, N.Y.)

|August 21, 2010

まとめ

アクチンケーブルを使ってネスプリン2GとSUN2タンパク質を介して細胞核の位置を変更します. このアクチンに依存するメカニズムは,移動する細胞における核の移動とセンターソームの方向転換を駆動する.

科学分野:

細胞生物学細胞生物学
細胞骨格のダイナミクス
核力学核力学とは

背景:

核の位置づけは,細胞の移動と分化に極めて重要です.
多くの核の動きはマイクロチューブルに依存していますが,移動する線維芽細胞におけるセンターソームの方向転換のメカニズムはアクチンに依存しており,完全に理解されていません.

研究の目的:

アクチンに依存した核の移動と,ポラライズする線維芽細胞におけるセンターソームの方向転換の分子メカニズムを解明する.

主な方法:

核定位における核膜タンパク質 (ネスプリン2G,SUN2) と背面アクチンケーブルの役割を調査した.
ネスプリン2G,SUN2,アクチンの抑制を活用し,核の移動とセンターソームの方向転換への影響を評価した.

主要な成果:

Nesprin2GとSUN2は,核の位置変更時に,背面アクチンケーブルで組み立てられ,移動しました.
ネスプリン2G,SUN2またはアクチンの抑制により,核の移動とセンターソームの方向転換が妨げられました.

結論:

核膜タンパク質であるネスプリン2GとSUN2は,背面アクチンケーブルと結合することで核の動きを媒介する.
このアクチン・ケーブル・核膜結合は,核定位における力伝導のための新しいメカニズムであり,プラズマ膜におけるインテグリン機能に類似しています.

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