Biomolecular Analysis of Proteins in Visual Disease

描述（由申请人提供）：视网膜ATP结合盒（ABC）转运蛋白（ABCR）与几种遗传性视觉疾病综合征有关；包括Stargardt病、锥杆营养不良、黄斑部炎和年龄相关性黄斑变性（ARMD）。遗传分析的综述清楚地表明，在整个ABCR基因的保守结构域和非保守结构域中，错义氨基酸替换发生的频率相同。我们的总体目标是研究ABCR蛋白的作用机制，以及在Stargardt病和ARMD中观察到的基因突变如何影响视网膜运输中的能量转导，从而在未来开发出新的更精确的治疗方法。

DESCRIPTION (provided by applicant): The retinal ATP binding cassette (ABC) transporter, ABCR, is linked to several inherited visual disease syndromes; including Stargardt disease, cone-rod dystrophy, fundus flavimacultitis and age related macular degeneration (ARMD). An overview of genetic analyses clearly demonstrate that missense amino acid substitutions occur with equal frequency in conserved domains, as well as non-conserved domains throughout the whole of the ABCR gene. Our overall aim is to investigate the mechanism of action of ABCR protein and how genetic mutations observed in Stargardt disease and ARMD influence energy transduction in retinal transport so that new and more precise therapies may be developed in the future. (1) We are carrying out a detailed structure-function analysis of nucleotide binding and hydrolysis by ABCR. We plan to test the hypothesis that certain mutations observed in Stargardt disease and ARMD lead to conformational changes which in turn influence nucleotide binding and hydrolysis. This will help us to develop a predictive model for the likely effect of a given mutation on the enzymatic activity and associated structural changes in ABCR. (2) Analyze extracellular domain mutations in substrate (retinal) binding. In this specific aim we address, what are the biochemical consequences of extracellular domain mutations in ABCR function. We will approach this important question from several directions. We will investigate (a) identification of ECD mutations that lead to a loss of retinal stimulation of ATPase; (b) retinal binding by recombinant ECD polypeptides.