Rab5是一种信号GTPase,它参与受体氨酸激酶受体的actin重塑
Letizia Lanzetti1, Andrea Palamidessi, Liliana Areces
1Istituto Europeo di Oncologia, Via Ripamonti 435, 20141 Milan, Italy.
Nature
|May 21, 2004
概括
拉布5GTPase控制细胞内贩运和行动蛋白重塑. 它的效应因子RN-tre对于巨细胞形成至关重要,并将Rab5与actin细胞骨联系起来,揭示了一个关键的信号通路.
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:
- Rab5,一个小的GTPase,调节细胞内贩运和内体动态.
- 受体氨酸激酶 (RTKs) 激活Rab5,促使人们对其在RTK效应器通路中的作用进行调查.
研究的目的:
- 为了确定Rab5是否参与RTK诱导的效应因子通路.
- 阐明Rab5影响actin重塑的分子机制.
主要方法:
- 研究了Rab5在RTK诱导的行为因子重塑中的作用,特别是圆形纹.
- 确定了RN-tre作为一个Rab5特定的GTPase激活蛋白 (GAP) 和效应剂.
- 检查了RN-tre在巨细胞结核中的功能及其与F-actin和actinin-4的相互作用.
主要成果:
- Rab5对于RTK诱导的圆形形是必不可少的,需要从Rab5,酸-3-OH酶和Rac.同时发出信号.
- RN-tre同时作为Rab5-GAP和效应器,调解Rab5向actin细胞骨架的信号传递.
- RN-tre对巨细胞细胞形成至关重要,并与F-actin和actinin-4相互作用,这表明它在actin网络形成中的作用.
结论:
- Rab5在RTK通路中起到信号GTPase的作用.
- RN-tre是Rab5的一个关键下游效应因子,将其与actin细胞骨架动力学和巨细胞细胞形成联系起来.
- Rab5-RN-tre-actin通路对于细胞过程至关重要,例如循环和巨细胞.
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相关概念视频
GTPases and their Regulation
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Large G-proteins, also known...
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Rab proteins switch between a cytosolic, GDP-bound inactive state and a membrane-anchored, GTP-bound active state. By themselves, Rabs show slow rates of GDP/GTP exchange and GTP hydrolysis. Thus, Rab proteins are considered...
Rab proteins switch between a cytosolic, GDP-bound inactive state and a membrane-anchored, GTP-bound active state. By themselves, Rabs show slow rates of GDP/GTP exchange and GTP hydrolysis. Thus, Rab proteins are considered...
GTPases and their Regulation
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, also known...
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Small GTPases - Ras and Rho
Ras and Rho are small monomeric GTPases that act downstream of receptor tyrosine kinase (RTK) and regulate various cellular processes. These GTPases switch between active and inactive states by binding to guanine nucleotides.
Three regulatory proteins control their activity:
Three regulatory proteins control their activity:
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Heterotrimeric G proteins are guanine nucleotide-binding proteins. As the name suggests, heterotrimeric G proteins are composed of three subunits: alpha, beta, and gamma. They remain GDP-bound or GTP-bound inside the cells and switch between inactive/active states. The Gα subunit possesses the nucleotide-binding pocket that binds guanine nucleotides and switches between GDP or GTP-bound states. In contrast, the Gꞵ and Gγ subunits are always bound together with high affinity and are together...
