バクテリアの洞窟の構成的な形成

Piers J Walser¹, Nicholas Ariotti, Mark Howes

¹The University of Queensland, Institute for Molecular Bioscience, Brisbane, Queensland 4072, Australia. piers.walser@nhsbt.nhs.uk

Cell

|August 21, 2012

まとめ

バクテリアのカヴェオリンタンパク質発現は,洞窟のような膀を形成する. これらの異質な洞窟は,ネイティブの構造を模倣し,標的の配送のために分子をカプセル化することができます.

科学分野:

細胞生物学細胞生物学
バイオケミストリーバイオケミストリー
構造生物学構造生物学とは

背景:

ケベオリン (caveolin) は,動物細胞の重要な表面穴であるケベオラ (caveolae) を形成するための必須タンパク質である.
洞窟形成の正確なメカニズムは,まだ完全に理解されていません.

研究の目的:

簡素化されたプロカリオット系におけるケベオリン自己組み立てと膜芽生えを調査する.
カベオリンが哺乳類の細胞の外で機能的な洞窟のような構造を形成できるかどうかを判断する.

主な方法:

細胞内膜が欠けているプロカリオット宿主における野生型および突然変異のケベオリンの発現.
クリオエレクトロントモグラフィーで,カベオリン誘発の膀の構造と配置を分析します.
サイトプラズマ膜から発芽する膀の分析と,周辺プラズマ溶液の封じ込め.

主要な成果:

ワイルド型カベオリンがプロカリオット発現すると,ポリマーカベオリンを含む細胞プラズマ胞子が形成される.
これらの異質な洞窟 (h-caveolae) は,構造的には,サイズと洞窟の密度でネイティブの洞窟に類似していました.
クリオエレクトロントモグラフィーにより,小胞体内のカベオリンオリゴマーの多面構造の配置が明らかにされました.

結論:

カヴェオリンは,複雑な真核生物の機械から独立して,細胞のないシステムで,洞窟のような構造に自己組み立てることができます.
形成には,細胞プラズマ膜から芽が芽生え,明確な脂質領域が形成されます.
これらのh-caveolaeは分子をカプセル化することができ,標的の配送アプリケーションの潜在能力を提供します.

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