LENS PROTEINS: CHANGES DUE TO CATARACTOGENIC AGENTS

在衰老和白内障形成过程中，晶状体蛋白经历了一种 化学和物理修饰的次数，即， 聚集、色素沉着和增加不溶性物质的产生 蛋白质。人们认为，构象变化与 在这些过程中。到目前为止的调查表明 光、钙离子、糖类分子(在糖尿病白内障中)等 在导致这种蛋白质修饰的因素中， 可能最终导致白内障的形成。 我们的目标是： 1.深入了解正常晶状体的分子特征 蛋白质，并了解其修饰的原因。我们 将研究：(A)亚基的分子结构 α和β晶体蛋白；以及(B)相互作用的性质 晶状体中的晶体。 2.描述应用时分子特性的变化 下列致白内障药物：(A)光；(B)活性物质 氧的种类；(C)糖，糖的代谢物；和 糖基化；(D)钙离子；和(E)氨基甲酰化。 3.用类似的方法研究完整的晶状体。 在模型研究中，将使用牛透镜。研究将会是 扩展到人类晶状体，老少咸宜，正常和白内障 (如可用)。 常规凝胶层析法分离晶状体晶体蛋白 并用高效液相色谱对其进行了表征。适当的化学，生化， 流体力学和光谱技术将被用来 监视构象方面及其变化。这些措施包括 凝胶色谱、凝胶电泳法、沉淀法 超速离心法，荧光法，磷光法， 圆二色谱和拉曼共振谱。

During aging and cataractogenesis, lens proteins undergo a number of chemical and physical modifications, namely, aggregation, pigmentation, and increased production of insoluble proteins. It is believed that conformational change is associated with these processes. Investigations to date have suggested that light, calcium ion, sugar molecules (in diabetic cataract), etc. are among the causative factors for this protein modification which may eventually lead to cataract formation. Our aims are: 1. To gain insight into the molecular features of normal lens proteins and to understand the cause of their modifications. We will investigate: (a) the molecular structure of the subunits of alpha- and beta crystallins; and (b) the nature of interactions among lens crystallins. 2. To describe changes in the molecular features upon application of the following cataractogenic agents: (a) light; (b) active species of oxygen; (c) sugar, metabolites of sugar, and glycosylation; (d) Ca2+; and (e) carbamylation. 3. To study intact lenses in a similar manner. For model studies, bovine lenses will be used. Studies will be extended to human lenses, old and young, normal and cataractous (as available). Lens crystallin will be isolated routinely by gel chromatography and characterized by HPLC. Appropriate chemical, biochemical, hydrodynamic, and spectroscopic techniques will be used to monitor conformational aspects and their changes. These include gel chromatography, gel electrophoresis, sedimentation equilibrium by ultracentrifuge, fluorescence, phosphorescence, circular dichroism and Raman resonance spectroscopy.