サイトダイレクトされたアクチンフィラメントアセンブリを伴う新しい形の成長の運動性
P Forscher1, C H Lin, C Thompson
1Department of Biology, Yale University, New Haven, Connecticut 06511.
Nature
|June 11, 1992
まとめ
ポリケーション性マイクロビーズは,神経細胞の成長コンでアクチンアセンブリを誘発し,ビーズの動きのための力を生み出します. これは,アクチンフィラメントの組み立てが,膜-細胞骨格界面における細胞力の生成のための重要なメカニズムであることを示唆しています.
科学分野:
- 細胞生物学 細胞生物学
- 神経科学は神経科学である.
- バイオフィジックス 生物物理学
背景:
- 細胞外信号は,軸索の誘導を含む,指向された細胞運動に不可欠な細胞骨格動態を調節する.
- ニューロンの成長コンと運動細胞は,おそらく膜タンパク質とF-アクチンネットワーク経由で粒子の転位を示す.
研究 の 目的:
- ニューロンの成長コーンの膜とポリケチオン微粒子の相互作用によって誘発される新しい形の運動性を調査する.
- 力の発生と粒子の移動を媒介する細胞内アクチンアセンブリの役割を明らかにする.
主な方法:
- ニューロンの成長コーンの膜と相互作用するためにポリケチオン微粒子を利用しました.
- 細胞内アクチンフィラメントの組立と力産生を観察・分析した.
- 観察されたビーズの動きを細胞内細菌の推進機構と比較した.
主要な成果:
- 数珠結合は,急速に誘発された細胞内アクチンフィラメントアセンブリである.
- このアセンブリは,成長コーンの表面に沿ってビーズの動きを駆動するのに十分な力を生み出しました.
- 細胞外ビーズの運動性は,宿主細胞のアクチンリダイレクションによる細胞内バクテリアの推進を模倣した.
結論:
- ポリケーション性微粒子の相互作用は,成長コンのユニークな運動力メカニズムを刺激します.
- サイト・ディレクテッド・アクチン・フィラメント・アセンブリは,膜-細胞骨格界面で力を発生させる強力な細胞機構である.
- このメカニズムは,異なる細胞プロセスや有機体において保存されることがあります.
関連する概念動画
Actin Polymerization
Actin polymerization occurs through the head-to-tail association of binding sites on monomeric actin or G-actin to form filamentous or F-actin. The polymerization can be divided into three phases ̶ nucleation, elongation, and steady-state phase.
The nucleation phase involves forming a stable nucleus consisting of three actin monomers to form a new actin filament. Actin-binding proteins such as formins and Arp2/3 complex help filament growth post-nucleation. The Formins form straight actin...
The nucleation phase involves forming a stable nucleus consisting of three actin monomers to form a new actin filament. Actin-binding proteins such as formins and Arp2/3 complex help filament growth post-nucleation. The Formins form straight actin...
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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.
Mechanism of Filopodia Formation
Filopodia are thin, actin-rich cellular protrusions that play an important role in many fundamental cellular functions. They vary in their occurrence, length, and positioning in different cell types, suggesting their diverse roles.
Their main function is to guide migrating cells during normal tissue morphogenesis or cancer metastasis by recognizing and making initial contacts with the extracellular matrix. However, they can also act as stationary cell anchors or help to establish communication...
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Mechanism of Lamellipodia Formation
Cells migrating in response to external stimuli form lamellipodia, which are thin membrane protrusions supported by a mesh of linked, branched, or unbranched actin filaments. These actin filaments interact with myosin motor proteins, creating the dynamic actomyosin complex within the cytoskeleton. Contractility, or the ability to generate contractile stress, is inherent to the actomyosin complex. It helps cells detect the stiffness of the surrounding ECM and exert contractile force for...
Actin Treadmilling
Actin filaments undergo polymerization and depolymerization from either end. The polymerization and depolymerization rates depend on the cytosolic concentration of free G-actins. The polymerization rate is generally higher at the plus or barbed end, while the depolymerization rate is higher at the minus or pointed end. At a steady state, critical concentration describes the concentration of free G-actin monomers at which the polymerization rate at the plus end is equal to that of the...


