动氨酸单体影响Xenopus环酶相关蛋白1和动氨酸丝之间的相互作用
Phuong Doan N Nguyen1, Hiroshi Abe2, Shoichiro Ono3,4
1Division of Nano Life Science, Graduate School of Frontier Science Initiative, Kanazawa University, Kakuma-machi, Kanazawa, Ishikawa, Japan.
bioRxiv : the preprint server for biology
|August 20, 2025
概括
循环酶相关蛋白 (CAP) 调节了行动蛋白的动态. 与自由CAP不同的是,CAP-actin复合体的结合时间更长,并且更喜欢actin丝的侧面,这表明了新的调节机制.
科学领域:
- 细胞生物学 细胞生物学
- 生物化学 生物化学
- 生物物理学的生物物理.
背景情况:
- 已知循环酶相关蛋白 (CAP) 能结合乙单体和细丝,调节乙动态.
- 已观察到CAP与乙单体形成稳定的复合物,但其功能意义尚不清楚.
- 之前的研究表明,Xenopus环酶相关蛋白1 (XCAP1) 与actin形成4:4复合体.
研究的目的:
- 为了研究无动蛋白XCAP1和XCAP1-动蛋白复合体与动蛋白丝的相互作用.
- 确定与XCAP1结合的活性单体如何影响其对活性丝的结合行为.
- 阐明CAP-actin复合体在调节actin动态中的功能意义.
主要方法:
- 使用高速原子力显微镜 (HS-AFM) 可视化了XCAP1和XCAP1-actin复合体与actin纤维的结合.
- 进行了对结合停留时间和在actin纤维上的位置偏好进行定量分析.
主要成果:
- 无动氨酸的XCAP1对动氨酸丝进行了暂时的结合,停留时间约为0.2秒.
- 同样,XCAP1-actin复合物也表现出暂时的结合,但与无actin的XCAP1.1相比,其停留时间长了3到5倍.
- 无动氨酸的XCAP1结合于线丝的两侧和两端,偏好端,而XCAP1-actin复合物则偏好结合于线丝的两侧.
结论:
- 乙单体与XCAP1的结合改变了它与乙丝的相互作用动态.
- 不同的结合方式表明一种新的机制,即CAP-actin复合物调节CAP对actin动态的影响.
- 这一发现为CAP-actin复合体在涉及actin重塑的细胞过程中的功能作用提供了新的见解.
相关概念视频
Generation of Straight or Branched Actin Filaments
3.0K
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...
3.0K
Actin Polymerization and Cell Motility
5.4K
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....
5.4K
Actin Filament Depolymerization
3.2K
Actin filaments (F-actin) are composed of actin subunits. The dissociation of actin monomers can occur from either end of F-actin. The rate of dissociation is faster from the minus-end or the pointed end, where the actin subunits exist with a bound ADP, together known as ADP-actin. The depolymerization of F-actin is aided by proteins, including the actin-depolymerizing factor (ADF) and cofilin family of proteins, gelsolin, and glia maturation factor (GMF).
In F-actin, the ADF/cofilin proteins...
In F-actin, the ADF/cofilin proteins...
3.2K
Introduction to Actin
5.3K
Actin is a highly conserved cytoskeletal protein found abundantly in eukaryotic cells. It constitutes 10% weight of the total cellular protein in muscle cells, while in non-muscle cells, it is lower and makes up around 1–5 percent of the total cell protein. Actin found in the unicellular amoebae and complex multicellular animals is around 80% similar, demonstrating their conservation over a billion years of evolution. Actin coding genes are conserved within species and across...
5.3K
Actin Polymerization
6.9K
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...
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...
6.9K
Formation of Higher-order Actin Filaments
3.1K
The polymerization of G-actin monomers into filamentous F-actin is a multi-step process. Once the F-actins are formed, they can bundle together in different arrangements to form higher-order networks and regulate cellular functions. Common examples include the formation of lamellipodia and filopodia at the cell's leading edge by actin reorganization in a migrating cell. The microvilli on the brush border epithelial cells are also formed through the F-actin network.
The high-order actin...
The high-order actin...
3.1K


