STRUCTURAL STUDIES OF ARRESTINS

拟议研究的长期目标是了解 视紫红质在光转导中的生化步骤 激活，通过它的失活，和它的再生。这个 光解产物失活与再生的重要性 视紫红质最近变得明显，因为这些功能的故障 光转导过程中的生化事件导致退化 光感受器和视力障碍。阿雷斯汀是一种 光传导失活的重要组成部分和一种 强大的自身抗原。阐明其结构和功能 芦丁将极大地提高我们对其发病机制的认识。 涉及这种蛋白质功能障碍的疾病。 申请人建议检查其结构特性 Arrestin和p44(arrestin的剪接变体)以及它们如何 参与光传导和视觉的量化 周而复始。申请人试图了解：(1)功能和 Arrestin的结构域，继续他的结晶学 方法；(2)截断Arrestin的功能性质 在Oguchi病中发现，以及arrestin的分子基础 异质性；(3)Arrestin和Arrestin的功能差异 P44使用电生理和生化方法；(4) Arrestin和p44的一级序列中的区域相互作用 光解视紫红质，在生理上相关的磷酸化 站点(Ser338、Ser343和Ser334)；最后(5)停用 光解视紫红质与突变小鼠视觉周期中的步进 其中视紫红质激酶或arrestin基因被 有针对性的突变。

The long-term objective of the proposed studies is to understand the biochemical steps in phototransduction, leading from rhodopsin activation, through its inactivation, and to its regeneration. The importance of inactivation and regeneration of photolyzed rhodopsin has become apparent recently, as malfunctions of these biochemical events during phototransduction lead to degeneration of photoreceptors and impairment of vision. Arrestin is an important component of inactivation of phototransduction and a potent auto-antigen. Elucidation of the structure and function of arrestin will greatly enhance our understanding of the pathogenesis of disease involving dysfunction of this protein. The applicant proposes to examine the structural properties of arrestin and P44 (a splice variant of arrestin) and how they participate in the quanching of phototransduction and in the visual cycle. The applicant seeks to understand: (1) the functional and structural domains of arrestin, continuing his crystallographic approaches; (2) the functional properties of truncated arrestin found in Oguchi Disease, and the molecular basis of arrestin heterogeneity; (3) the functional differences between arrestin and p44 using electrophysiological and biochemical methods; (4) which regions in the primary sequence of arrestin and p44 interact with photolyzed rhodopsin, phosphorylated at physiologically relevant sites (Ser338, Ser343, and Ser334); and finally (5) inactivation of photolyzed rhodopsin and steps in the visual cycle of mutant mice in which the rhodopsin kinase or arrestin genes were disrupted by targeted mutagenesis.