G蛋白及其GTPase激活蛋白在血小板中的作用
Lorna O'Donoghue1,2, Albert Smolenski1,2
1UCD School of Medicine, University College Dublin, UCD Conway Institute, Belfield, Dublin 4, Ireland.
Bioscience reports
|May 29, 2024
概括
血小板使用G蛋白,瓜核酸交换因子 (GEFs) 和GTPase激活蛋白 (GAPs) 来应对血管损伤. 本综述详细介绍了调节血小板信号网络的GAP.
科学领域:
- 血液学 血液学 血液学
- 细胞信号传输 细胞信号传输
- 分子生物学分子生物学
背景情况:
- 血小板对于血管完整性至关重要,在受伤之前静止地循环.
- 在激活后,血小板聚合并分泌颗粒,这一过程由复杂的信号网络调节.
- 关氨酸核酸交换因子 (GEF) 和GTPase激活蛋白 (GAP) 是血小板中G蛋白信号的关键调节者.
研究的目的:
- 审查GAPs在血小板内调节小G蛋白和异构三基G蛋白中的作用.
- 突出GAPs在整合G蛋白信号与血小板中的其他细胞过程中的重要性.
主要方法:
- 本综述综合了最近的蛋白质组学研究中的发现,这些研究确定了血小板中的G蛋白,GEF和GAP.
- 专注于对调节Arf,Rab,Ras和Rho家族的GAPs以及异构三基G蛋白的特征.
主要成果:
- 蛋白质组学已经在血小板中确定了一组全面的G蛋白,GEF和GAP.
- 许多GEF和GAP是血小板特异性的,具有有限的详细表征.
- GEF和GAP关键控制活跃的GTP结合的G蛋白水平,响应血小板激活和抑制信号.
结论:
- 通过调节G蛋白活性,GAPs是血小板功能的关键调节者.
- 这些调节性蛋白质将G蛋白信号与其他血小板功能相结合.
- 对血小板特异性GAP的进一步研究是有必要的,以充分理解它们在血管健康和疾病中的作用.
相关概念视频
02:14GTPases and their Regulation
8.3K
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,...
8.3K
01:22Activation and Inactivation of G Proteins
7.0K
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...
7.0K
01:24Small GTPases - Ras and Rho
3.9K
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:
3.9K
01:22Amplifying Signals via Enzymatic Cascade
8.5K
When a ligand binds to a cell-surface receptor, the receptor's intracellular domain changes shape, which may either activate its enzyme function or allow its binding to other molecules. The initial signal is amplified by most signal transduction pathways. This means that a single ligand molecule can activate multiple molecules of a downstream target. Proteins that relay a signal are most commonly phosphorylated at one or more sites, activating or inactivating the protein. Kinases catalyze...
8.5K
01:18Structure and Function of Platelets
1.1K
The cell fragments known as platelets are disc-shaped, with an average diameter of about 3 μm and a thickness of roughly 1 μm. They play a crucial role in the body's vascular clotting system, which also involves plasma proteins, blood cells, and blood vessel tissues.
Platelets are continually replenished, circulating in the bloodstream for 9-12 days before being removed by phagocytes, primarily in the spleen. A microliter of circulating blood contains between 150,000 and 450,000...
Platelets are continually replenished, circulating in the bloodstream for 9-12 days before being removed by phagocytes, primarily in the spleen. A microliter of circulating blood contains between 150,000 and 450,000...
1.1K
01:09GPCRs Regulate Adenylyl Cylase Activity
5.5K
Some GPCRs transmit signals through adenylyl cyclase (AC), a transmembrane enzyme. AC helps synthesize second messenger cyclic adenosine monophosphate (cAMP). AC catalyzes cyclization reaction and converts ATP to cAMP by releasing a pyrophosphate. The pyrophosphate is further hydrolyzed to phosphate by the enzyme pyrophosphatase, which drives cAMP synthesis to completion. However, cAMP is rapidly degraded to 5′ AMP by the enzymes phosphodiesterase (PDE), preventing overstimulation of...
5.5K