アラビドプシスの皮質配列における持続的な微小管のトレードミリング
Sidney L Shaw1, Roheena Kamyar, David W Ehrhardt
1Department of Biological Sciences, Stanford University, Stanford, CA 94305, USA.
まとめ
植物細胞は,新しいハイブリッドトレッドミリングメカニズムを使用して,組織化されたマイクロチューブル配列を形成します. 微小管は両端で成長し,縮小し,細胞皮質内の持続的な移動と再配置を可能にします.
科学分野:
- 細胞生物学 細胞生物学
- 植物細胞のダイナミクス
- 細胞骨格の組織 細胞骨格の組織
背景:
- 植物細胞には,マイクロチューブルを固定するための中央組織センターが欠けている.
- マイクロチューブル配列は,植物細胞の構造と機能に不可欠です.
- 微小管のダイナミクスを理解することは,細胞形態変異の鍵です.
研究 の 目的:
- 植物細胞におけるマイクロチューブル配列形成のメカニズムを調査する.
- 細胞皮質でマイクロチューブルがどのように組織されているかを明らかにするために.
- 個々の微小管のダイナミクスを理解するために in vivo.
主な方法:
- アラビドプシスの個々のマイクロチューブルをインビボ画像化.
- マイクロチューブルポリメリゼーションとデポリメリゼーションのダイナミクスの分析.
- 微小管の成長と縮小の両端の振る舞いの観察.
主要な成果:
- 新しいマイクロチューブルは細胞皮質で始まり,両端でダイナミクスを示します.
- ポリメリゼーションバイアスのダイナミック・インスタビリティと遅いデポリメリゼーションを含むハイブリッド・トレッドミリング・メカニズムは,マイクロチューブル移動を駆動する.
- この運動性は,微小管の位置変更,方向転換,および束縛につながり,配列の組織を変更します.
結論:
- 植物細胞は,皮質の微小管組織のためのユニークなハイブリッドトレッドミリングメカニズムを使用します.
- 微小管の運動性は,細胞骨格配列のダイナミックな再編成に大きく貢献する.
- このプロセスは,植物細胞の微小管組織を維持および変更するために不可欠です.
関連する概念動画
Assembly of Complex Microtubule Structures
Complex microtubule structures are present in resting cells and in dividing cells. In resting cells, they are responsible for maintaining the cellular architecture, tracks for intracellular transport, positioning of organelles, assembly of cilia and flagella. They mediate the bipolar spindle assembly for chromosomal segregation and positioning of the cell division plate in dividing cells. The formation of microtubule complex structures depends on the cell type, cell stage, and cell function.
Microtubules in Cell Motility
Microtubules are thick hollow cylindrical proteins that help form the cytoskeleton. Microtubules have varied roles in the cell. These filaments help form cellular appendages like cilia and flagella, which are responsible for locomotion. The cilia arise from basal bodies, separated from the main body by a membrane-like structure forming the transition zone. This zone is the gate for the entry of lipids and proteins, creating a unique composition of lipids and proteins in the ciliary membrane and...
Microtubule Instability
Microtubules are hollow cylindrical filaments having a diameter of approximately 25 nm and a length that varies from 200 nm to 25 μm. GTP-bound tubulin subunits form αβ-heterodimers for microtubule assembly. These core building blocks interact longitudinally, polymerizing into protofilaments. The protofilaments then interact with one another through lateral bonding forces to form stable cylindrical microtubules. These cylindrical filaments are dynamic as they undergo repeated assembly and...
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...
Role of Microtubules in Cell Wall Deposition
Microtubules are small hollow tubes in eukaryotic cells. The cell wall microtubules are polymerized dimers of two globular proteins, α-tubulin and β-tubulin, two globular proteins. With a diameter of about 25 nm, microtubules are the widest components of the cytoskeleton. They help the cell resist compression and provide a track along which vesicles move through the cell or pull replicated chromosomes to opposite ends of a dividing cell. Microtubules go through quick cycles of disassembly and...
Microtubules in Cell Motility
Microtubules are thick hollow cylindrical proteins that help form the cytoskeleton. Microtubules have varied roles in the cell. These filaments help form cellular appendages like cilia and flagella, which are responsible for locomotion. The cilia arise from basal bodies, separated from the main body by a membrane-like structure forming the transition zone. This zone is the gate for the entry of lipids and proteins, creating a unique composition of lipids and proteins in the ciliary membrane and...


