円筒状の脂質膜テザーで測定されたepsin N端ホモロジー領域による曲線感知

Benjamin R Capraro¹, Youngdae Yoon, Wonhwa Cho

¹Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.

Journal of the American Chemical Society

|January 7, 2010

まとめ

エプシンタンパク質は,細胞がエンドサイトーシス中に膜の曲線を感知し形作ることで,細胞が膀を形成するのを助けます. この研究では,エプシンを定量化しています.

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
分子ダイナミクス分子ダイナミクス

背景:

クラトリン媒介の内分細胞化は,細胞のプロセスにとって極めて重要です.
エプシンタンパク質は,膀形成のために高い膜曲線を生成すると仮定されています.
タンパク質と膜の相互作用を理解することは,細胞の再編成の鍵です.

研究の目的:

エプシンN端ホモロジー (ENTH) ドメインの曲率依存度を体系的に定量化する.
膜の曲線感知と生成におけるエプシンの役割を評価する.
エンドサイト性タンパク質の熱力学的曲率-組成結合係数を測定する.

主な方法:

巨大なユニラメラー膀 (GUVs) とマイクロピペット吸入を使用しました.
制御された曲率のシリンダ状の膜テザーを作成しました.
光顕微鏡を用いた膜に結合したENTHドメインの面積密度を定量化.

主要な成果:

膜に結合したENTHの再分割が,膀から高度に曲げられた膜に観察された.
epsin. の曲率組成結合係数を決定しました.
膜の曲率とエプシン密度の間の直接的な関係を示した.

結論:

エプシンタンパク質は,細胞膜の曲線感知と生成に寄与する可能性がある.
開発された方法は,分子相互作用をマクロスコーピック膜改造にリンクする方法を提供します.
この研究は,細胞膜ダイナミクスにおけるタンパク質の役割を特徴づけるのに役立ちます.

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