"コアトーマー"とは,クラトリンで覆われていないゴルギ輸送小胞のサブユニットを含む細胞性タンパク質複合体である
M G Waters1, T Serafini, J E Rothman
1Department of Molecular Biology, Princeton University, New Jersey 08544.
Nature
|January 17, 1991
まとめ
研究者らは,コアトーマーと呼ばれる細胞塩基複合体 (cytosol complex) を特定し,浄化し,その中に重要なゴルギ水泡のコートタンパク質が含まれている. この発見は,膜芽生えと膀形成におけるタンパク質の役割を理解するのに役立ちます.
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.
- タンパク質生化学 タンパク質生化学
背景:
- ゴルギ系ベシクルは,コートタンパク質を輸送に使用します.
- 特定のコートタンパク質 (アルファ,ベータ,ガンマ,デルタ-COP) は既知の成分である.
研究 の 目的:
- ゴルギの膀のコートタンパク質の細胞複合体を特定し,浄化する.
- この複合体の組成と性質を特徴づけるために.
主な方法:
- サイトゾール複合体の浄化.
- 分割されていないサイトゾールのゲル濾過.
- 分子質量 (Mr) によるタンパク質サブユニットの分析.
主要な成果:
- コアトーマーと呼ばれる細胞複合体が特定され,浄化されました.
- コアトーマーには,アルファ-COP,ベータ-COP,ガンマ-COP,デルタ-COP,その他のポリペプチド (36K,35K,20K) が含まれています.
- ベータ-COPは,コアトーマー複合体内でのみ発見されました.
結論:
- コアトメルは,組立していないゴルギコーティングベシクルの前身である可能性が高い.
- コアトメアの浄化により,膜芽生えにおけるコートタンパク質の機能に関する研究が容易になります.
- コートタンパク質の役割の研究には,精製された細胞のないシステムが必要である.
関連する概念動画
COP Coated Vesicles
Membrane-enclosed structures called vesicles transport proteins and lipids across the cell. The vesicles derive their cargo from the plasma membrane, Golgi, ER, or endosome. Coated vesicles are spherical, protein-coated carriers with a 50–100 nm diameter that mediate bidirectional transport between the ER and the Golgi. The distribution of proteins between the ER and Golgi complex is dynamic and is maintained by different coated vesicles. Their formation is driven by the assembly of different...
Coat Assembly and GTPases
Vesicles incorporate different coat protein subunits in different cell locations, which changes the properties of the coat, such as the shape and geometry of the transport vesicles. Thus, vesicle coat proteins also play a significant role in cargo selection.
Coat assembly depends on the local availability of phosphatidylinositol phosphates or PIPs and GTP-binding proteins. Adaptor proteins, which link the coat proteins to the membrane, bind to these PIPs and play a crucial role in controlling...
Coat assembly depends on the local availability of phosphatidylinositol phosphates or PIPs and GTP-binding proteins. Adaptor proteins, which link the coat proteins to the membrane, bind to these PIPs and play a crucial role in controlling...
Vesicular Tubular Clusters
After budding out from the ER membrane, some COPII vesicles lose their coat and fuse with one another to form larger vesicles and interconnected tubules called vesicular tubular clusters or VTCs. These clusters constitute a compartment at the ER-Golgi interface known as ERGIC (Endoplasmic Reticulum Golgi Intermediate Compartment). The ERGIC is a mobile membrane-bound cargo transport system that sorts proteins secreted from ER and delivers them to the Golgi.
With the help of motor proteins such...
With the help of motor proteins such...
Golgi Matrix Proteins
Golgi matrix proteins are a group of highly dynamic proteins that maintain the stacked structure of Golgi. These proteins adapt to rapid morphological changes of the Golgi during the cell cycle. During cell division, mild proteolysis removes these connections resulting in Golgi unstacking. In The daughter cells, these proteins help reassemble the unstacked Golgi.
One of the first identified Golgi matrix proteins was GM130, a rod-like protein located in the cis-Golgi. Subsequently, many Golgi...
One of the first identified Golgi matrix proteins was GM130, a rod-like protein located in the cis-Golgi. Subsequently, many Golgi...
Transport Across the Golgi
While it is unclear how molecules move between adjacent Golgi cisternae, it is apparent that the molecules move from cis- cisterna, the entry face, to the trans- cisterna, the exit face. Experiments initially suggested vesicles that bud from one cisterna and fuse with the next cisterna to transport proteins between the cisternae. This vesicular transport model describes the Golgi apparatus as a relatively static structure with a unique enzyme composition in each cisterna. Molecules are...
Clathrin Coated Vesicles
Clathrin-coated vesicles use endocytosis to transport receptors and lysosomal hydrolases from the Golgi to the lysosome in the late secretory pathway. Clathrin-mediated endocytosis was the first described endocytic process, and Clathrin-coated vesicles remain one of the most well-studied transport vesicles. The molecular machinery that generates clathrin-coated vesicles comprises over 50 proteins that precisely coordinate vesicle formation. Cell surface receptors concentrated in indented sites...


