2M型·维勒布兰德病的结构解析动态
Alexander Tischer1, Laurie Moon-Tasson1, Matthew Auton1
1Division of Hematology, Departments of Internal Medicine and Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota, USA.
Journal of thrombosis and haemostasis : JTH
|January 5, 2025
概括
2M型威尔布兰德病是由威尔布兰德因子 (VWF) 的A1域中的两个结构变化引起的. 这些变化要么使A1域过度稳定,要么错误折叠,从而损害了血小板粘附.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 血液学 血液学 血液学
背景情况:
- 维尔布兰德因子 (VWF) 血小板粘附性A1域中的基因决定的氨基酸替代导致维尔布兰德病的增益 (2B型) 或功能丧失 (2M型) 现型.
- 之前的研究表明,结构缺陷,包括错误折叠和超稳定,改变了A1域的稳定性和折叠.
研究的目的:
- 在VWF A1域中研究15种额外的2M型变体和2种多态的结构/功能关系.
- 为了充分了解2M型·维勒布兰德病表型的基础分子机制.
主要方法:
- 使用循环二重化,光和热量计来评估蛋白质结构和稳定性.
- 用-交换质谱和表面等离子体共振来分析蛋白质动态和结合亲和力.
- 在切割流下测量了血小板粘附,以评估功能后果.
主要成果:
- 六种变体被原生折叠,其中四种表现出高稳定性.
- 九种变体显示出无序的A1域,其特点是减少α螺旋结构和展开的度.
- GPIbα结合亲和力和血小板粘附动态与螺旋结构有很强的相关性,局部结构性扰动显著减少结合亲和力和剪切依赖粘附.
结论:
- 在A1域中的超稳定动态可以损害流动下血小板与VWF的附着.
- 在特定的A1域区域中,变异诱导的局部性疾病导致错误折叠和废止的血小板粘附.
- 这些相反的构造性质代表了两种不同的VWF结构类,它们驱动了2M型·维勒布兰德病表型.
相关概念视频
Formation of the Platelet Plug
4.2K
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...
4.2K
Anticoagulant Drugs: Low-Molecular-Weight Heparins
607
Hemostasis is a crucial process that prevents excessive blood loss from damaged blood vessels. It involves various mechanisms such as vasoconstriction, platelet adhesion and activation, and fibrin formation. The importance of each mechanism depends on the type of vessel injury. In contrast, thrombosis is the abnormal formation of a blood clot within the blood vessels, leading to potential complications if the clot obstructs blood flow. Thrombosis can be caused by increased coagulability of the...
607
Vascular Spasm
1.2K
The vascular phase, also known as vasospasm, is the initial stage of hemostasis, crucial for preventing excessive bleeding when a blood vessel is injured. After a vessel is cut, nerves in the damaged area trigger pain and other sensory impulses. Simultaneously, the smooth muscles in the vessel wall contract, resulting in a vascular spasm. This contraction reduces the vessel's diameter at the injury site, slowing or stopping blood loss through the vessel wall. Vascular spasms typically last...
1.2K
Extrinsic and Intrinsic Pathways of Hemostasis
5.3K
Blood clotting or coagulation involves extrinsic and intrinsic pathways, which ultimately merge into the common pathway, forming a fibrin clot.
The Extrinsic Pathway
The extrinsic pathway of coagulation is typically initiated by tissue damage that exposes blood to tissue factor (TF), a protein released by the damaged tissue cells outside the blood vessels—this interaction with TF triggers biochemical reactions involving specific clotting factors. The key player here is Factor VII, which...
The Extrinsic Pathway
The extrinsic pathway of coagulation is typically initiated by tissue damage that exposes blood to tissue factor (TF), a protein released by the damaged tissue cells outside the blood vessels—this interaction with TF triggers biochemical reactions involving specific clotting factors. The key player here is Factor VII, which...
5.3K
Disorders of Hemostasis
696
Hemostasis, the process that stops bleeding after a blood vessel injury, is crucial for maintaining the integrity of the circulatory system. However, disorders of hemostasis can disrupt this delicate balance, leading to either excessive clotting or bleeding. These disorders can be broadly classified into thromboembolic disorders and bleeding disorders.
Thromboembolic Disorders
Two factors primarily cause thromboembolic conditions.
Thromboembolic Disorders
Two factors primarily cause thromboembolic conditions.
696


