COPIとCOPIIで覆われた水泡は,酵母菌のエンドプラズマの網膜から直接芽生えています
S Y Bednarek1, M Ravazzola, M Hosobuchi
1Department of Molecular and Cell Biology, Howard Hughes Medical Institute, University of California, Berkeley 94720, USA.
Cell
|December 29, 1995
まとめ
酵母タンパク質のCOPIIとCOPIは,核包膜から独立した輸送小胞を形成します. タンパク質の輸送に不可欠なこれらの膀は,エンドプラズマ網膜の居住タンパク質とは独立して生成されます.
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.
- タンパク質の輸送
背景:
- Sec13p-Sec31p,Sec23p-Sec24p,Sar1pで構成されるCOPIIコートは,タンパク質輸送小胞を生成することが知られている.
- コアトーマーとArf1pを含むCOPIコートも,膀輸送を媒介する.
研究 の 目的:
- イーストの核包膜からCOPIとCOPIIベジケルの形成を調査する.
- COPIとCOPIIによる輸送経路の異なる役割と特徴を決定する.
主な方法:
- 薄切片と免疫電子顕微鏡を用いて,膀の形成を視覚化しました.
- 膀の含有量とブレフェルディンAに対する感受性の分析が行われました.
主要な成果:
- 浄化されたCOPII成分は,単離された酵母核から直接輸送小胞を形成します.
- COPIの構成要素は,核の封筒からコーティングされた芽と膀を形成した.
- COPI媒介の膀形成はブレフェルディンAによって抑制されたが,COPIIは抑制されなかった.
- 両方の膀型にはER居住タンパク質がなく,Golgi標的型タンパク質が含まれていた.
結論:
- COPIとCOPIIは,エンドプラズマ網膜から発生する異なる膀輸送経路を媒介する.
- これらの経路は,特定の貨物と標的の機械を持つ異なる膀集団を利用します.
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