Gain-of-Function Variant p.Pro2555Arg of von Willebrand Factor Increases Aggregate Size through Altering Stem Dynamics.
Gain-of-Function Variant p.Pro2555Arg of von Willebrand Factor Increases Aggregate Size through Altering Stem Dynamics.
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DOI：
10.1055/a-1344-4405
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发表时间：
2022-03
影响因子：
6.7
通讯作者：
Brehm MA
中科院分区：
文献类型：
--
作者：
Huck V;Chen PC;Xu ER;Tischer A;Klemm U;Aponte-Santamaría C;Mess C;Obser T;Kutzki F;König G;Denis CV;Gräter F;Wilmanns M;Auton M;Schneider SW;Schneppenheim R;Hennig J;Brehm MA
多聚体血浆糖蛋白（GP）血管性血友病因子（VWF）在主要止血过程中最常用于将血小板募集到损伤部位。通常，VWF基因突变导致止血活性丧失，从而导致出血性疾病血管性血友病。通过采用锥和血小板聚集测定和微流控分析，我们发现了血小板GPIIb/IIIa依赖性血栓前功能（GOF）的变异p.Pro2555Arg，位于C4域，导致血小板聚集体的大小增加。我们使用圆二色光谱，小角X-射线散射，核磁共振光谱，分子动力学模拟上的单个C4域，和二聚野生型和p.Pro2555Arg结构进行了补充的生物物理和结构研究。C4-p.Pro2555Arg保留了总体结构构象，少数替代构象群体表现出铰链柔性增加和构象交换缓慢。二聚体蛋白质变得无序和更灵活。我们的数据表明，GOF不影响GPIIb/IIIa的C4结构域的结合亲和力。相反，增加的VWF二聚体的灵活性增强血小板结合位点的时间可及性。使用跨学科的方法，我们发现p.Pro2555Arg是第一个VWF变体，它增加了血小板聚集体的大小，并显示了VWF茎区的剪切依赖性功能，它可以通过突变变得过度活跃。VWF的血栓前GOF变体是血栓栓塞事件的VWF相关病理机制的新概念，其对血管健康具有普遍意义，但尚未在诊断中考虑。因此，应提高对它们构成的风险的认识。此外，我们的数据暗示C4结构域作为一种新的抗血栓药物靶点。
The multimeric plasma glycoprotein (GP) von Willebrand factor (VWF) is best known for recruiting platelets to sites of injury during primary hemostasis. Generally, mutations in the VWF gene lead to loss of hemostatic activity and thus the bleeding disorder von Willebrand disease. By employing cone and platelet aggregometry and microfluidic assays, we uncovered a platelet GPIIb/IIIa-dependent prothrombotic gain of function (GOF) for variant p.Pro2555Arg, located in the C4 domain, leading to an increase in platelet aggregate size. We performed complementary biophysical and structural investigations using circular dichroism spectra, small-angle X-ray scattering, nuclear magnetic resonance spectroscopy, molecular dynamics simulations on the single C4 domain, and dimeric wild-type and p.Pro2555Arg constructs. C4-p.Pro2555Arg retained the overall structural conformation with minor populations of alternative conformations exhibiting increased hinge flexibility and slow conformational exchange. The dimeric protein becomes disordered and more flexible. Our data suggest that the GOF does not affect the binding affinity of the C4 domain for GPIIb/IIIa. Instead, the increased VWF dimer flexibility enhances temporal accessibility of platelet-binding sites. Using an interdisciplinary approach, we revealed that p.Pro2555Arg is the first VWF variant, which increases platelet aggregate size and shows a shear-dependent function of the VWF stem region, which can become hyperactive through mutations. Prothrombotic GOF variants of VWF are a novel concept of a VWF-associated pathomechanism of thromboembolic events, which is of general interest to vascular health but not yet considered in diagnostics. Thus, awareness should be raised for the risk they pose. Furthermore, our data implicate the C4 domain as a novel antithrombotic drug target.
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影响因子：
6.1
作者：
Konarev, PV;Volkov, VV;Svergun, DI
通讯作者：
Svergun, DI
影响因子：
20.3
作者：
Ruggeri, Zaverio M.;Orje, Jennifer N.;Reininger, Armin J.
通讯作者：
Reininger, Armin J.
影响因子：
6.7
作者：
Huck, Volker;Schneider, Matthias F.;Schneider, Stefan W.
通讯作者：
Schneider, Stefan W.
影响因子：
2.7
作者：
Ahlner, Alexandra;Carlsson, Mats;Lundstrom, Patrik
通讯作者：
Lundstrom, Patrik
影响因子：
16.6
作者：
de Witt, Susanne M.;Swieringa, Frauke;Cavill, Rachel;Lamers, Moniek M. E.;van Kruchten, Roger;Mastenbroek, Tom;Baaten, Constance;Coort, Susan;Pugh, Nicholas;Schulz, Ansgar;Scharrer, Inge;Jurk, Kerstin;Zieger, Barbara;Clemetson, Kenneth J.;Farndale, Richard W.;Heemskerk, Johan W. M.;Cosemans, Judith M. E. M.
通讯作者：
Cosemans, Judith M. E. M.