通过GEF和GAP对Cdc42GTPase循环的寡合化依赖和协同调节
Sophie Tschirpke1, Werner K-G Daalman1, Frank van Opstal1
1Bionanoscience Department, Delft University of Technology, Delft, The Netherlands.
EMBO reports
|February 9, 2026
概括
细胞极性依赖于Cdc42蛋白调节. 酵母蛋白Cdc24 (GEF) 和Rga2 (GAP) 显示出协同作用,确保有效的细胞极性建立. 这种协同作用可能在真核生物中得到保护.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 生物化学 生物化学
背景情况:
- 细胞极性对于基本的细胞过程如分裂,生长和运动性至关重要.
- 在酵母菌 (Saccharomyces cerevisiae) 中,Rho-GTPase Cdc42 是极性建立的核心.
- Cdc42的活性受到关氨酸核酸交换因子 (GEFs) 和GTPase激活蛋白 (GAPs) 的严格调节.
研究的目的:
- 调查Cdc42.2.的动态调节机制.
- 描述 GEF Cdc24 和 GAP Rga2.2. 的依赖于度的活动.
- 阐明Cdc24和Rga2在调节Cdc42.4中的协同作用.
主要方法:
- 实验室GTPase试验被用于测量酶活性.
- 分析了Cdc24和Rga2的度依赖的动态概况.
- 评估了Cdc24和Rga2之间的结合相互作用.
主要成果:
- Cdc24的GEF活性显示出非线性,依赖于寡合化的特征,可能是由于缓解了自我抑制.
- Rga2的GAP活性表现出和动力学,这可能是由于寡合化后的自我抑制引起的.
- 观察到Cdc24和Rga2之间的强烈协同作用,由弱Cdc24-Rga2结合驱动,这表明Cdc24减轻Rga2的自我抑制.
结论:
- Cdc24和Rga2之间的协同相互作用使Cdc42 GTPase循环在不同速率上的有效调节成为可能.
- 这种强有力的调节有助于在酵母中有效地建立细胞极性.
- 已确定的GEF-GAP协同作用被提出为其他真核生物体中保存的调节机制.
相关概念视频
GTPases and their Regulation
9.9K
Guanine nucleotide-binding proteins (G-proteins), also known as GTPases, are a superfamily of proteins that regulate many cellular processes, such as cell signaling, vesicular transport, and the regulation of cell shape and motility. Mutation or dysfunction of these proteins can lead to disease. There are around 40,000 known G-proteins that can broadly be classified into two groups ‒ small G-proteins consisting of a single domain and large multi-domain G-proteins.
Large G-proteins,...
Large G-proteins,...
9.9K
GTPases and their Regulation
3.0K
3.0K
Hormonal Regulation of the Menstrual Cycle
1.7K
The ovarian cycle regulates endometrial changes throughout a single menstrual cycle via the coordinated action of gonadotrophin-releasing hormone (GnRH) and gonadotrophins.
At puberty, GnRH begins a pulsatile release pattern, which triggers the anterior pituitary gland to secrete follicle-stimulating hormone (FSH) and luteinizing hormone (LH). The frequency and amplitude of GnRH pulses vary across the menstrual cycle, with faster pulses favoring LH release and slower pulses favoring FSH...
At puberty, GnRH begins a pulsatile release pattern, which triggers the anterior pituitary gland to secrete follicle-stimulating hormone (FSH) and luteinizing hormone (LH). The frequency and amplitude of GnRH pulses vary across the menstrual cycle, with faster pulses favoring LH release and slower pulses favoring FSH...
1.7K
Gap Junctions
57.3K
Multicellular organisms employ a variety of ways for cells to communicate with each other. Gap junctions are specialized proteins that form pores between neighboring cells in animals, connecting the cytoplasm between the two, and allowing for the exchange of molecules and ions. They are found in a wide range of invertebrate and vertebrate species, mediate numerous functions including cell differentiation and development, and are associated with numerous human diseases, including cardiac and...
57.3K
Gap Junctions
9.7K
The cytoplasm of adjacent animal cells can exchange small molecules, ions, and secondary messengers via the communication channels which form the gap junctions. These junctions comprise a few hundred to thousands of molecular channels, each made of two halves, called the connexon hemichannel. A connexon is a hexamer of six transmembrane connexin proteins, which assemble radially, thus forming a pore or channel in the center. One connexon hemichannel docks with a corresponding connexon on the...
9.7K
Regulated Protein Degradation
8.9K
It is vital to regulate the activity of enzymatic as well as non-enzymatic proteins inside the cell. This can be achieved either through creating a balance between their rate of synthesis and degradation or regulating the intrinsic activity of the protein. Both these regulation mechanisms play an essential role in the normal functioning of cells.
Protein degradation plays two important roles in the cells. It helps to protect cells from misfolded or damaged proteins before they lead to a...
Protein degradation plays two important roles in the cells. It helps to protect cells from misfolded or damaged proteins before they lead to a...
8.9K


