胶原介导的VWF的激活是启动血小板发挥凝止血功能的关键事件，受血管壁面剪应力和化学信号的双重调控，这一尚不清晰的力化学耦合诱导过程，是当前细胞分子生物力学中的前沿热点课题。本项目拟基于胶原和2B型突变将通过减弱VWF-A1A2A3内部功能结构域间的相互作用来降低A1A2A3封闭结构的力学稳定性这一猜想，以力诱导的A1A2A3三联体构象的改变为研究切入点，结合生物力学建模与分子动力学模拟、残基突变、显微电镜、分子影像、AFM和流动腔等实验技术，测定A1、A2和A3单体间的反应动力学常数及力依赖特性，探明不同剪切力条件下结合在胶原上的A1A2A3的拓扑结构及其与GPIba的结合亲和力，力图揭示力和配体或2B型突变协同介导的VWF活化的生物力学调控机制和分子结构基础，旨在加深理解凝止血生理及病理过程，为心脑血管疾病患者的临床治疗和康复、相关分子药物靶点的发现和抗体药物的设计提供新思路。

Regulated by vascular wall shear stress, the collage-mediated VWF activation is a first key event for triggering the hemostatic function of platelet. This force-dependent and ligand-induced process is not yet well clear, and become a focus in cellular and molecular biomechanics research. In the present proposal, the force-induced transition from closed to opened conformation of VWF-A1A2A3 triplet domain is selected as starting point of this research, based on the supposition that both collagen and type 2B mutations will reduce the mechanical stability of the closed A1A2A3 structure by weakening the force-dependent interaction between internal functional subdomains of A1A2A3. Through combining with biomechanical modeling, molecular dynamics simulation, residue mutation, electron microscope, molecular imaging, AFM and flow chamber techniques, we will measure the force-dependent kinetics between monomer A1, A2 and A3 of VWF, reveal the topology and affinity (to GPIb) of A1A2A3 bound with collagen under different shear stresses, and attempt to uncover the mechanical mechanism and molecular basis of the type 2B mutation- and collagen-induced VWF activation. This research should be useful in better understanding of physiological and pathological processes of the hemostasis and thrombosis, in providing and novel strategy for clinical treatment and rehabilitation, in discovery of new drug targets, and in development of new antibody drugs, for cardiovascular and cerebrovascular disease.