コート・アセンブリとベシクル・ブドリングの結合と,仮の貨物受容器の包装の結合

M Bremser¹, W Nickel, M Schweikert

¹Biochemie-Zentrum Heidelberg, University of Heidelberg, Germany.

Cell

|March 3, 1999

まとめ

コアトーマー媒介のCOPIコーティングベシクル芽生えには,特定のタンパク質とGTPが必要です. ゴルギ輸送に不可欠なこのプロセスは,二価コアトーマー相互作用を通じて,貨物の吸収を膀形成と結びつける.

科学分野:

細胞生物学細胞生物学
分子生物学は分子生物学である.
メンブラン取引メンブラン取引

背景:

COPIで覆われた膀は,ゴルジ装置内の逆行輸送を媒介する.
コアトーマー (コアトーマー) は,細胞性タンパク質複合体であり,COPIの膀形成に不可欠である.
ゴルギ膜のCOPIコート組成を開始する正確な分子機構は,現在調査中です.

研究の目的:

ゴルギのような脂質二重層からCOPIコーティングされた膀芽の分子要件を解明する.
カーゴ受容体とARF-GTPがコアトーマー募集と膀形成における役割を調査する.
in vitroでCOPIの水泡芽を研究するためのリポソームベースのシステムを確立する.

主な方法:

ゴルギの膜の組成を模倣するプロテオリポソームを使用して,COPIでコーティングされた膀芽の復元.
浄化されたコアトーマー,ARF,GTPをブッダリングアッセイに含める.
膀の特徴 (直径,密度,形質) と芽生え効率の分析.

主要な成果:

COPIでコーティングされた膀の芽生えは,コアトーマー,ARF-GTP,および特定の負荷/受容体の細胞質尾 (p24タンパク質,KKXX信号) に依存しています.
リポソーム由来COPIベシクルは,サイズ,密度,温度依存性など,ネイティブベシクルの性質に類似する性質を示します.
双価相互作用モデルは,コアトーマー組成を説明し,貨物結合と膀形成を結びつける.

結論:

コアトーマーと膜に結合したARF-GTPと貨物尾の双価相互作用がCOPIコート組立を駆動する.
このメカニズムは,貨物の認識と輸送ベジクルの形成との間の直接的なリンクを提供します.
この研究は,ゴルギ逆行トランスポートの開始を理解するための簡素化されたモデルを提供します.

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