VWF - Collagen Interactions Studied with Single Molecule Force Spectroscopy
VWF - Collagen Interactions Studied with Single Molecule Force Spectroscopy
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VWF - 用单分子力谱研究胶原蛋白相互作用
DOI：
10.1016/j.bpj.2013.11.2551
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发表时间：
2014
影响因子：
3.4
通讯作者：
Hinterdorfer P
中科院分区：
文献类型：
--
作者：
Posch S;Obser T;Brehm AM;Gruber HJ;Schneppenheim R;Tampé R;Hinterdorfer P
血管性血友病因子(von Willebrand factor，VWF)是一种巨大的多聚体蛋白，在止血中起关键作用。作为止血的初始事件，胶原结合的部位位于VWF的A1和A3区域。据信，III型胶原与A3结构域相互作用，VI型胶原与A1结构域相互作用。用分子识别力光谱(MRFS)研究了这些相互作用的作用力和动力学，使用具有致密聚乙二醇链和末端苯甲醛官能团的底物来固定化胶原。VWF结构域A1-A2-A3与III型胶原之间的结合比VI型胶原与A1-A2-A3A1-结构域之间的结合更稳定，表明A3是胶原的主要结合域。我们还研究了A1-A2-A3(S1731T)A3区的一个突变，通过ELISA检测，该突变显示III型胶原结合略有减少。在MRFS中，III型胶原和S1731T突变体之间的相互作用在稳定性上与野生型结构没有显着差异。这些数据与我们的观察一致，即S1731T突变的人只表现出轻微的出血倾向或没有明显的出血倾向。我们进一步比较了A1-A2-A3和A1-A2的VI型胶原结合能力。当A3结构域缺失时，VI型胶原与A1之间的结合更强。此外，注入游离的A2结构域干扰了胶原VI-A1的相互作用，但不影响III型胶原与A3结构域的相互作用，表明A1结构域也可能与A2相互作用。我们的数据可以得出胶原-VWF-结构域相互作用的详细分子图像。这项工作得到了德国研究基金会(1543-SHENC的DFG研究单位)和奥地利科学基金(项目I 767-B11)的支持。
Von Willebrand factor (VWF) is a huge multimeric protein that plays a key role in hemostasis. Sites for collagen binding, an initial event of hemostasis, are located in domains A1 and A3 of VWF. Collagen III is believed to interact with the A3-domain, and collagen VI with the A1-domain. The forces and the dynamics of these interactions were investigated with molecular recognition force spectroscopy (MRFS), using substrates with a dense layer of poly (ethylene glycol) chains and terminal benzaldehyde functions for covalent immobilization of collagen. The bond between collagen III and the A3-domain of VWF domain construct A1-A2-A3 was more stable than the bond between collagen VI and the A1-domain of A1-A2-A3, suggesting that A3 is the main binding domain for collagen. We also investigated a mutation in the A3-domain of A1-A2-A3 (S1731T) that shows a slight decrease of collagen III binding determined by ELISA. In MRFS interactions between collagen III and the S1731T mutant showed no significant difference in stability compared to the wild type construct. These data are consistent with our observation that persons with mutation S1731T exhibit only a mild or no significant bleeding tendency. We further compared the collagen VI binding capability of A1-A2-A3 and A1-A2. The bond between collagen VI and A1 was stronger when the A3-domain was missing. In addition, the injection of free A2-domains disturbed the collagen VI-A1 interaction, but had no effect on interactions between collagen III and the A3-domain, indicating that domain A1 might also interact with A2. Our data allow deriving a detailed molecular picture on the interplay of collagen-VWF-domain interactions. This work was supported by the German Research Foundation (DFG Research Unit FOR 1543-SHENC) and the Austrian Science Fund (Project I 767-B11).