COPIでコーティングされた膀の構造は,代替コアトーマー構造と相互作用を明らかにします
Marco Faini1, Simone Prinz, Rainer Beck
1Structural and Computational Biology Unit, European Molecular Biology Laboratory, Meyerhofstrasse 1, 69117 Heidelberg, Germany.
Science (New York, N.Y.)
|May 26, 2012
まとめ
この研究では,コアトーマー複合体がCOPIでコーティングされた膀を形成し,さまざまな形状とサイズを採用する方法が明らかになりました. この発見は,真核細胞の細胞内輸送のためにタンパク質コートがどのように組み立てられるかについての新しい視点を提供します.
科学分野:
- 細胞生物学 細胞生物学
- 構造生物学 構造生物学とは
- バイオケミストリー バイオケミストリー
背景:
- ユカリオット細胞の細胞内輸送は,コーティングされた膀に依存しています.
- COPI,COPII,クラトリンのような原型タンパク質コートは,このプロセスにおいて極めて重要です.
- COPIIとクラトリンのコートの構造に関する以前の研究では,定期的にケージを組み立てることを提案しました.
研究 の 目的:
- COPIでコーティングされた個々の膜膀の3次元構造を決定する.
- 膜膀のCOPIコートの組立メカニズムを理解するために.
- 膀のサイズと形状の変動性の構造的基礎を解明する.
主な方法:
- クリオエレクトロントモグラフィーは,COPIでコーティングされた個々の膀を画像化するために使用されました.
- サブトモグラムの平均は,in vitroで再構成された芽生えた反応に適用されました.
- コートタンパク質複合体 (コアトーマー) 構成の高解像度構造分析.
主要な成果:
- COPIでコーティングされた個々の膜膀の構造が解明されました.
- コアトーマー複合体は,別の形状を採用することが観察されました.
- 膀のサイズと形状の変動性はコアトーマー相互作用と関連していた.
結論:
- 膀のCOPIコート組成は,以前のモデルとは根本的に異なります.
- コアトメアの形状の変化により,サイズと形状が変化する膀が形成されます.
- これは,COPIでコーティングされた小胞を通して細胞内輸送の調節に関する新しい洞察を提供します.
関連する概念動画
00:59COP 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...
01:32Pinching-off of Coated Vesicles
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01:33Coat 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...
01:12Clathrin 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...
01:45Vesicular 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...
01:25Structure of Cadherins
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