通过相同的信号通路,LAIR-1和PECAM-1功能抑制GPVI介导的血小板激活
Christopher W Smith1, Zoltan Nagy2, Mitchell J Geer3
1Institute of Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom.
Research and practice in thrombosis and haemostasis
|September 25, 2024
概括
白细胞相关免疫球蛋白类受体-1 (LAIR-1) 和血小板内皮细胞粘附分子-1 (PECAM-1) 通过相同的途径抑制血小板激活. 双重淘汰的小鼠显示血小板数量增加,但血栓形成正常,这表明它们有共同的调节作用.
科学领域:
- 免疫学 免疫学 免疫学
- 血液学 血液学 血液学
- 分子生物学分子生物学
背景情况:
- 血小板反应对于血栓形成控制至关重要.
- 血小板内皮细胞粘附分子-1 (PECAM-1) 负面调节血小板-原相互作用.
- 白细胞相关免疫球蛋白类受体-1 (LAIR-1) 负面调节血小板的产生和反应性.
研究的目的:
- 研究LAIR-1和PECAM-1在巨核细胞发育和血小板产生中的作用.
- 使用双淘汰赛 (DKO) 鼠标模型确定LAIR-1和PECAM-1之间的功能冗余.
主要方法:
- 在巨核细胞中对LAIR-1和PECAM-1表达的西部抹杀.
- 流式细胞计和光显微镜用于巨核细胞化和血小板形成.
- 在野生型,LAIR-1,PECAM-1和DKO小鼠中的血小板功能和信号比较的聚合计,流细胞计和西部涂抹.
- FeCl3 动脉模型用于血栓形成的评估.
主要成果:
- 在LAIR-1/PECAM-1 DKO小鼠中,血小板数增加了17%.
- 巨核细胞的发育和 ploidy 没有受到 LAIR-1 或 PECAM-1 缺陷的影响.
- 来自LAIR-1,PECAM-1和DKO小鼠的血小板表现出对原蛋白的同等高反应性.
- DKO小鼠在体内表现出正常的血栓形成,尽管血小板功能发生了改变.
结论:
- 通过相同的信号通路,LAIR-1和PECAM-1抑制GPVI介导的血小板激活.
- 在体内,LAIR-1和PECAM-1的联合缺乏不会增加血栓的形成.
- 这些发现突显了免疫受体氨酸基抑制动机含受体在调节血小板数量和功能的作用.
相关概念视频
IP3/DAG Signaling Pathway
11.9K
Membrane lipids such as phosphatidylinositol (PI) are precursors for several membrane-bound and soluble second messengers. Specific kinases phosphorylate PI and produce phosphorylated inositol phospholipids. One such inositol phospholipids are the phosphatidylinositol-4,5 bisphosphate [PI(4,5)P2], present in the inner half of the lipid bilayer. Upon ligand binding, GPCR stimulates Gq proteins to turn on phospholipase Cꞵ. Activated phospholipase Cꞵ cleaves PI(4,5)P2 and...
11.9K
Interactions Between Signaling Pathways
6.2K
Signaling cascades usually lack linearity. Multiple pathways interact and regulate one another, allowing cells to integrate and respond to diverse environmental stimuli.
Convergence and divergence, and cross-talk between signaling pathways
Two distinct signaling pathways can converge on a single functional unit, which may either be a single protein or a complex of proteins. The response is either functionally distinct or synergistic between the two pathways but different from the response...
Convergence and divergence, and cross-talk between signaling pathways
Two distinct signaling pathways can converge on a single functional unit, which may either be a single protein or a complex of proteins. The response is either functionally distinct or synergistic between the two pathways but different from the response...
6.2K
Amplifying Signals via Enzymatic Cascade
8.4K
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...
8.4K
The JAK-STAT Signaling Pathway
8.7K
Several cytokine receptors have tightly bound Janus kinase or JAK proteins attached at their cytosolic tail. Small signaling molecules such as cytokines, growth hormones, or prolactins bind to the cytokine receptors and initiate their dimerization. The dimerization brings the cytosolic JAKs together that trans-phosphorylate and activates each other. The activated JAKs now phosphorylate cytosolic tails of the cytokine receptors, which serve as binding sites for adaptor proteins such as SH2...
8.7K
Formation of the Platelet Plug
5.2K
The platelet phase, the second stage of hemostasis, commences around 15-20 seconds after an injury. It follows and overlaps with the vascular phase, during which blood vessels constrict to minimize blood loss.
As the injured blood vessel contracts, endothelial cells undergo contraction, revealing collagen fibers in the basement membrane and underlying connective tissue. Furthermore, the plasma membrane of endothelial cells becomes adhesive, preparing the site for platelet adhesion. Platelets...
As the injured blood vessel contracts, endothelial cells undergo contraction, revealing collagen fibers in the basement membrane and underlying connective tissue. Furthermore, the plasma membrane of endothelial cells becomes adhesive, preparing the site for platelet adhesion. Platelets...
5.2K
GPCRs Regulate Adenylyl Cylase Activity
5.3K
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...
5.3K


