ESR SPIN LABEL STUDIES OF FIBRONECTINS

纤维连接蛋白是一种多功能糖蛋白， 凝血、细胞粘附、分化和胚胎发育。 的 纤维连接蛋白多功能活性的基础似乎存在于 在这些分子的多域结构中。 我们建议使用 电子自旋共振（ESR）自旋标记方法来研究动态 纤连蛋白分子不同区域之间的相互作用。 的 氨基转移酶交联位点和游离巯基 蛋白质将被特定的自旋标记物选择性地修饰。 的 纤连蛋白的运动将使用常规和 饱和转移ESR方法。 环境条件的影响 (e.g., pH值、温度和离子强度）以及与其他 生理物质（例如，肝素、胶原蛋白和纤维蛋白原） 评价纤连蛋白的构象状态。 尝试将 用于研究解决方案中的相似性和/或相异性 血浆和细胞纤连蛋白之间的性质。 此外该 氨基转移酶交联位点和游离巯基 蛋白质也将被特异性荧光标记选择性地修饰。 标签 不同区域间邻近关系的变化 纤连蛋白分子受环境因素或 与其他生物分子的相互作用将通过使用 荧光能量转移法。 这些研究应该提供更深入的 了解不同区域的三维关系， 纤连蛋白。 了解纤连蛋白的结构和动力学 解释了人体的各种生理功能 归因于蛋白质。 最后，纤连蛋白是一种原型蛋白质， 其他粘附蛋白如层粘连蛋白和软骨连接蛋白。 我们的长期 目的是研究这些细胞粘附分子的结构和功能 糖蛋白，并解开这些蛋白质相互作用的方式， 细胞表面和细胞外基质的动态结构。

Fibronectins are multifunctional glycoproteins that participate in blood coagulation, cell adhesion, differentiation and embryonic development. The basis of the multifunctional activities of fibronectins appears to reside in the multidomain structure of these molecules. We propose to use electron spin resonance (ESR) spin label methods to study the dynamic interactions between different regions of the fibronectin molecule. The transglutaminase crosslinking site and free sulfhydryl groups of the protein will be modified selectively with specific spin labels. The motions of fibronectin will be determined using both conventional and Saturation Transfer ESR methods. The effects of environmental conditions (e.g., pH, temperature and ionic strength) and interactions with other physiological substances (e.g., heparin, collagen, and fibrinogen) on the conformational states of fibronectins will be evaluated. Attempts will made to investigate the similarity and/or dissimilarity in solution properties between plasma and cellular fibronectins. In addition, the transglutaminase crosslinking site and free sulfhydryl groups of the protein will also be modified selectively with specific fluorescent labels. The changes in proximity relationship between different regions of the fibronectin molecule as affected by either environmental factors or interactions with other biomolecules will be determined by using fluorescence energy transfer methods. The studies should provide a deeper understanding of the three-dimensional relationships of various regions of fibronectin. Understanding the structure and dynamics of fibronectin underlies an interpretation of the vast array of physiological functions attributed to the protein. Finally, fibronectin is a prototype protein for other adhesive proteins such as laminin and chondronectin. Our long-term objective is to study the structure and function of these cell adhesive glycoproteins and to unravel the ways in which these proteins interact with the cell surface and the dynamic structure of extracellular matrices.