ESR SPIN LABEL STUDIES OF FIBRONECTINS

纤维连接蛋白是参与血液的多功能糖蛋白。 凝血、细胞黏附、分化和胚胎发育。这个 纤维连接蛋白多功能活性的基础似乎驻留在 在这些分子的多域结构中。我们建议使用 电子自旋共振(ESR)自旋标记法研究动力学 纤维连接蛋白分子不同区域之间的相互作用。这个 谷氨酰胺转胺酶的交联点和游离基 蛋白质将有选择地用特定的自旋标记进行修饰。这个 纤维连接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 (例如，pH、温度和离子强度)以及与其他 生理物质(如肝素、胶原和纤维蛋白原) 将评估纤维连接蛋白的构象状态。尝试将 用于研究溶液中的相似性和/或差异性 血浆和细胞纤维粘连蛋白之间的性质。此外， 谷氨酰胺转胺酶的交联点和游离基 蛋白质也将被选择性地用特定的荧光修饰 标签。不同区域之间邻近性关系的变化 纤维连接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 荧光能量传递方法。这些研究应该提供更深层次的 对中国各区域立体关系的认识 纤维连接蛋白。了解纤维连接蛋白的结构和动力学 是对大量生理功能的解释 归因于这种蛋白质。最后，纤维连接蛋白是一种原型蛋白 其他粘附性蛋白，如层粘连蛋白和软骨粘连蛋白。我们的长期合作 目的是研究这些细胞粘附剂的结构和功能。 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.