vWF结构域A/C区的自缔合分子效应及其对血小板信号传导的影响

血管性血友病因子(vWF)为血液循环中的多结构域蛋白大分子，其会自我组装成一系列分子量不同的多聚体，形成自缔合状态，在血小板的粘附和聚集过程中起重要作用。本项目首先应用酵母双杂交系统和噬菌体展示，确证vWF主要结构域的A/C区相互作用肽段并制备相应的抗体以用于选择性阻断vWF的自缔合；其次，研究A/C区融合表达的分子以巯基/二硫键交换形式而相互聚集的自缔合分子效应和机制。随后，在应用光谱检测方法分析vWF自缔合分子稳定性和趋势的基础上，观察由A/C区肽段制备的抗体对vWF的动态自缔合选择性阻断作用，精确定位能够影响vWF自缔合的A/C区潜在功能域。最后，分析vWF自缔合及其被A/C区抗体作用后对血小板聚集和活化的影响，并探讨相应的分子信号传导机制。本项目的完成有望阐明A/C 区所主导的新型vWF自缔合分子机制，这将为vWF自缔合发生和发展如何调控血小板功能变化，提供新的实验依据和理论指导。

von Willebrand factor (vWF) is a multi-domain glycoprotein in circulating blood plasma. It could self-associate into a series of multimers at different molecular weights. This process is named as self-association, which plays a critical role in mediating the adhesion and aggregation of platelets. We plan to utilize yeast two-hybrid system and phage-display technique to confirm the peptide interaction between A domain and C domain, and construct antibodies based on the interaction of A and C domain to selectively block vWF self-association. Secondly, we will study both the effect and the mechanism of self-association among fusion-peptides of A domain and C domain, which is accomplished via the transferring between thiol and disulfide bond. Thirdly, based on the results of the major tendency and stability of vWF self-association detected by spectrum method, we will study the selectively blocking function of antibodies to vWF self-association, and accurately position the potential functional domains for the blocking effect. Finally, we aim to study the effect of both vWF self-association and after being blocked by antibodies on the adhesion and aggregation of platelets, and involved signal pathways. Taken together, this study may clarify a novel molecular mechanism of vWF self-association via A and C domains, provide new experimental evidences and theoretical guidance for research concerning functional changes of platelet regulated by the initiation and development of vWF self-association.