関連する実験動画
Updated: Jul 10, 2026

08:57
Aip1p Dynamics Are Altered by the R256H Mutation in Actin
Published on: July 30, 2014
アクチン細胞骨格のプロカリオティック起源
F van den Ent1, L A Amos, J Löwe
1MRC Laboratory of Molecular Biology, Cambridge, UK. fent@mrc-lmb.cam.ac.uk
Nature
|September 7, 2001
まとめ
バクテリアはアクチンとチューブリンタンパク質の同類体を持っている. バクテリアのMreBタンパク質はアクチン状のフィラメントを形成し,プロカリオットの細胞形状決定におけるその役割を説明する.
科学分野:
- 微生物学 微生物学とは
- 細胞生物学 細胞生物学
- 構造生物学 構造生物学とは
背景:
- ユカリオット細胞は,アクチンとチューブリンによる細胞骨格ネットワークを持っています.
- 以前は,バクテリアにはこれらの繊維系がないと考えられていた.
研究 の 目的:
- バクテリアのMreBタンパク質と真核生物のアクチンとの構造的,機能的な類似性を調査する.
- プロカリオットにアクチンホモローグがあるかどうかを判断する.
主な方法:
- バクテリアのMreBタンパク質の結晶構造の解明.
- ユカリオットのアクチンと立体構造の比較.
- 原子解像度でのMreBプロトフィラメント構造の分析.
主要な成果:
- バクテリアのMreBタンパク質は,F-actin.に似たサブユニットリピートを持つフィラメントに組み合わさります.
- MreBとアクチンは,重要な3次元構造的類似性を示しています.
- MreBプロトフィラメントの構造は,F-アクチンアセンブリのモデルと一致しています.
- MreBは,細菌細胞の形状決定に関与する繊維状のスパイラルを形成します.
結論:
- Prokaryotesは,MreBタンパク質によって例示された,アクチンホモログを有しています.
- MreBのアクチンのような性質は,細菌細胞の形状を維持する役割を説明しています.
- この発見は,プロカリオットがチューブリン (FtsZ) とアクチン (MreB) の両方に同種を持つことを立証しています.
関連する概念動画
Introduction to the Cytoskeleton
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The cytoskeleton is a network of protein filaments present within the cell, having three distinct filaments ̶ microfilaments, microtubules, and intermediate filaments. Each has characteristic features that distinguish them, including the dynamics of their assembly and disassembly, mechanical properties, polarity, and the type of molecular motors associated with them. Earlier, they were thought to be present only in eukaryotic cells; however, their homologs were...
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The straight or branched structure formation of actin filaments is controlled by nucleating proteins such as the formins and Arp2/3 complex. Formin-mediated assembly results in straight filaments, whereas Arp2/3 protein complex-mediated assembly results in branched actin filaments.
Arp2/3 Complex
Arp2/3 complex is a seven-subunit complex consisting of two proteins similar to actin- Arp2 and Arp3, and five other subunits that help keep Arp2 and Arp3 inactive. When required, the complex is...
Arp2/3 Complex
Arp2/3 complex is a seven-subunit complex consisting of two proteins similar to actin- Arp2 and Arp3, and five other subunits that help keep Arp2 and Arp3 inactive. When required, the complex is...
Actin Polymerization and Cell Motility
Actin is a family of globular proteins that are highly abundant in eukaryotic cells. It makes up approximately 1-5% of total cell protein concentration. Actin monomers polymerize to form a complex network of polarized filaments, the actin cytoskeleton, that plays a crucial role in many cellular processes, including cell motility, division, endocytosis, and metastasis of cancer cells.
Actin cytoskeleton dynamics can produce pushing, pulling, and resistance forces that help the cell to migrate.
Actin cytoskeleton dynamics can produce pushing, pulling, and resistance forces that help the cell to migrate.

