Targeting the force-regulated von Willebrand Factor autoinhibitory module

针对力调节的冯维勒布兰德因子自抑制模块

• 批准号: 10459229
• 负责人: Nicholas Arce
• 金额: $ 3.43万
• 依托单位: EMORY UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-09-01 至 2022-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10459229
• 关键词: Adhesions; Antibodies; Binding; Binding Sites; Blood; Blood Circulation; Blood Platelets; Blood coagulation; Blood flow; C-terminal; Coagulation Process; Collagen; Communication; Deuterium; Discipline; Drug Design; Endogenous Factors; Epitopes; Event; Excision; Exhibits; Exogenous Factors; Experimental Designs; Factor VIII; Glycoproteins; Hemorrhage; Hemostatic function; Hydrogen; Informal Social Control; Injury; Integrin Binding; Investigation; Lead; Length; Ligands; Link; Mass Spectrum Analysis; Mechanoreceptors; Minor; Molecular; Molecular Conformation; Mutation; Myocardial Infarction; N-terminal; Oranges; Paper; Pathology; Pharmacology; Phenotype; Physiological; Platelet Activation; Platelet Glycoproteins; Platelet aggregation; Play; Positioning Attribute; Process; Proteins; Recombinants; Regulation; Regulatory Element; Research; Resistance; Risk; Role; Scientist; Site; Spectrum Analysis; Stabilizing Agents; Stretching; Stroke; Structure; Techniques; Testing; Thrombosis; Thrombotic Thrombocytopenic Purpura; Whole Blood; Work; Writing; acute coronary syndrome; base; beta 2-glycoprotein I; experimental study; gain of function; genetic regulatory protein; monomer; multidisciplinary; nanobodies; platelet function; prevent; response; shear stress; side effect; simulation; single molecule; therapeutic target; thrombotic; thrombotic complications; training opportunity; vascular injury; von Willebrand Disease; von Willebrand Factor

Project Summary Von Willebrand factor (VWF) is a multimeric blood glycoprotein that plays an important role in hemostasis and thrombosis. Platelet glycoprotein (GP)Ibα binds to the A1 domain of VWF, but only under high shear stress. This event triggers platelet activation and clot formation. We do not know how A1 can respond to only high shear. Recent papers suggest that the flanking regions that surround the A1 domain are responsible. These regions work together to shield the GPIbα-binding site on A1, acting as an autoinhibitory module (AIM) during normal blood flow. We hypothesize that force will dissociate the AIM, and that the activation of A1 is actually dissolution of the AIM-A1 interface. As the AIM is a discontinuous sequence, a tensile force applied would stretch the entire sequence, and disrupt the AIM. This leads to the possibility that stabilizing the AIM would allow for increased resistance to activation but would not directly interfere with the GPIbα-VWF interaction. Therapeutics that target GPIbα or A1 exhibit a bleeding phenotype, as this crucial interaction is prevented. Targeting the AIM would exhibit indirect modulation of the GPIbα-VWF interaction, whereby the AIM could still be dissociated by immense shear stress during injury. We hypothesize that under high shear, a critical tensile force is applied to VWF, that would abolish the AIM-A1 interface, allowing for exposure of A1. Specific Aim 1 is to define the dynamic response of the A1-AIM interface to tensile force. By investigating the structure and positioning of the AIM at the molecular level, we will determine the forces necessary to disrupt the AIM-A1 interaction and observe A1 binding of GPIbα. Specific Aim 2 is to determine if stabilization of the AIM will modulate VWF response to shear flow. The AIM may be utilized by endogenous regulatory proteins, or exogenous therapeutics targeted to the AIM, to impede VWF activation, but not hinder the binding event of VWF to platelets. We hypothesize that stabilization of the AIM is dependent on the shear force applied to VWF, and under conditions of high shear force, these effects may be reversible. The proposed studies will allow for wide-reaching investigation from the single molecule level to ex vivo blood simulation and allow for training opportunities to in multiple disciplines. Overall, completion of the proposed studies would provide support for the AIM as a therapeutic target for thrombotic diseases with minimal bleeding side effects.

项目摘要 von Willebrand因子（VWF）是一种多媒体血液糖蛋白，在止血和 血栓形成。血小板糖蛋白（GP）IBα与VWF的A1结构域结合，但仅在高剪切应力下。这 事件触发血小板激活和凝块形成。我们不知道A1只能响应高剪切。 最近的论文表明，围绕A1域的侧翼地区是造成的。这些地区 共同努力以在正常状态下充当自身抑制模块（AIM），以屏蔽A1上的GPIBα结合位点 血流（量。我们假设力将解离目标，并且A1的激活实际上是溶解的 AIM-A1接口。由于目的是不连续的序列，因此施加的拉伸力会拉伸整个 序列并破坏目标。这导致稳定目标允许增加的可能性 对激活的抗性，但不会直接干扰GPIBα-VWF相互作用。靶向的治疗剂 GPIBα或A1表现出出血表型，因为这种关键相互作用是防止的。针对目标 展示了GPIBα-VWF相互作用的间接调制，从而可以通过巨大的目标解散。 受伤期间的剪切应力。我们假设在高剪切的情况下，将临界拉伸力施加到VWF上， 会废除AIM-A1接口，允许暴露于A1。特定目标1是定义动态响应 拉伸力的A1-AIM界面。通过研究目标对分子的结构和定位 水平，我们将确定破坏AIM-A1相互作用并观察GPIBα的A1结合所需的力。 具体目标2是确定目标的稳定是否会调节对剪切流的vwf响应。目标可能 被内源性调节蛋白或针对目标的外源治疗所用，以阻碍VWF 激活，但不会阻碍VWF与血小板的结合事件。我们假设目标的稳定是 取决于施加到VWF的剪切力，在高剪切力的条件下，这些作用可能是 可逆。拟议的研究将允许从单分子水平进行广泛研究到EX 体内血液模拟，并为多个学科提供培训机会。总体而言，完成 拟议的研究将为目标提供支持，以作为最小的血栓性疾病的治疗靶点 出血副作用。