精製した成分で管状エンドプラズマ網の復元
Robert E Powers1,2, Songyu Wang1,2, Tina Y Liu1,2
1Howard Hughes Medical Institute, Harvard Medical School, 240 Longwood Avenue, Boston, Massachusetts 02115, USA.
Nature
|February 23, 2017
まとめ
細胞の臓器の形状は タンパク質の小さなセットによって維持されます このダイナミックな管状ネットワークには,連続した膜融合とエネルギー依存の安定状態プロセスが必要です.
科学分野:
- 細胞生物学
- 分子生物学
- バイオ物理学
背景:
- 臓器細胞の形状は細胞の機能に不可欠ですが,臓器細胞の形成のメカニズムはほとんど不明です.
- エンドプラズマ網 (ER) は,形成が完全に理解されていない複雑でダイナミックな管状のネットワークを特徴としています.
- いくつかの膜タンパク質がERネットワーク形成に関与しているが,その正確な役割と必要性は不明である.
研究 の 目的:
- エンドプラズマ網管網の形成と維持の基礎となる分子機構を調査する.
- Sey1p と Yop1p のような特定の膜タンパク質が ER 構造を形作る役割を決定する.
- 精製したタンパク質を使って ERネットワークの形成を再構成し,分析する.
主な方法:
- プロテオリポソームで精製されたエンドプラズマ網膜タンパク質 (Sey1pとYop1p) を使用してダイナミックな管状膜ネットワークを再構成する.
- ネットワーク形成を開始するためにGTP添加を使用し,ネットワーク維持を研究するためにGTP水解を阻害します.
- Sey1pの他の曲線安定化タンパク質 (レチクロン,REEPs) とその脊椎動物のオートログであるAtlastinとの相互作用を試験する.
主要な成果:
- セイ1p (膜融合GTPase) とYop1p (曲線安定タンパク質) を含むプロテオリポソームは,GTPを添加するとチューブ状のネットワークを形成する.
- Sey1pのGTP水解の阻害は迅速な管の断片化をもたらし,継続的な膜融合の必要性を示した.
- Sey1pは様々な曲線安定化タンパク質とネットワークを形成し,Atlastinは独立してGTP水解に依存するネットワークを形成しました.
結論:
- 臓器細胞の形,特にER管状のネットワークは,最小限のタンパク質で生成できます.
- ネットワークのメンテナンスはエネルギーに依存するプロセスで,膜融合と分解の間の安定状態を表します.
- Sey1pとAtlastinは,ERネットワークの構造とダイナミクスの重要なレギュレータとして機能します.
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