Phototransduction in health and disease

光转导在健康和疾病中的作用

基本信息

批准号：
8545387
负责人：
Paul S Park
金额：
$ 26万
依托单位：
CASE WESTERN RESERVE UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2011
资助国家：
美国
起止时间：
2011-09-30 至 2016-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8545387
关键词：
Animal Model Atomic Force Microscopy Binding Biochemical Biochemical Reaction Biological Biological Assay Cattle Cells Defect Degenerative Disorder Disease Energy Transfer Environment Event Functional disorder Future Genes Genetic Goals Grant Health Hot Spot Human In Vitro Inherited Knockout Mice Knowledge Laboratories Lead Light Link Membrane Membrane Proteins Methods Modeling Molecular Motion Mus Mutagenesis Mutation Night Blindness Opsin Pathology Patients Phenotype Photons Photoreceptors Phototransduction Property RPE65 protein Receptor Activation Research Resolution Retina Retinal Retinal Degeneration Retinal Diseases Retinal Dystrophy Retinitis Pigmentosa Rhodopsin Role Sampling Series Signal Transduction Spectrum Analysis Structure System Technology Testing Tissues Transgenic Mice United States National Institutes of Health Vision Vision Disorders Visual system structure Xenopus base biological systems chromophore combat dimer disease-causing mutation human disease insight mouse model mutant novel strategies novel therapeutic intervention programs receptor receptor structure function response retinal rods single molecule tool

项目摘要

DESCRIPTION (provided by applicant): Scotopic vision is initiated upon capture of a photon of light by rhodopsin molecules present in rod photoreceptor cells. The activation of the light receptor rhodopsin sets into motion a series of biochemical reactions called phototransduction, which leads to the hyperpolarization of the cell. The long-term goal of this research program is to understand the molecular mechanisms underlying the biochemical events in phototransduction under normal and diseased states. The starting point will be structure-function studies of rhodopsin. The importance of this molecule extends beyond its central role in phototransduction. The rhodopsin gene is a hot spot for mutations causing inherited vision disorders and these mutations are the leading cause of autosomal dominant retinitis pigmentosa, a heterogeneous group of inherited retinal degenerative diseases. Despite the wealth of knowledge available for rhodopsin, an accurate mechanism of its action is still unavailable and the mechanism underlying mutations in the light receptor causing vision disorders is unclear. Our immediate goal is to explore emerging ideas about the system that expand on classical dogma; namely, the notion of multiple active states of rhodopsin and the organization of rhodopsin into clusters of dimers. The aims of the proposal are thematically linked around understanding the fundamental molecular principles governing the activity of rhodopsin in normal and diseased conditions in people. In the first aim, we will test the implicit assumption made in most studies that the structure and function of human rhodopsin is similar to that of the receptor from better-studied mammalian species (bovine and mouse) used to understand human disease pathology. In the second aim, we will test the hypothesis that there are multiple active states of the receptor and that at least one of these states leads to constitutive activity in a rhodopsn mutant causing congenital stationary night blindness. In the third aim, we will test a putative rhodopsin dimer model and determine whether receptor oligomerization contributes to the phenotype of a rhodopsin mutant causing autosomal dominant retinitis pigmentosa. Significant technological advances are required to overcome the intrinsic difficulties in studying membrane proteins to observe native structural and molecular details that are important to understand the system. Our proposal utilizes several high-resolution biophysical methods including atomic force microscopy, single-molecule force spectroscopy and Forster resonance energy transfer. The combination of these methods with more traditional biochemical, biophysical, and genetic approaches will overcome the limitations of traditional assays alone and allow us to directly test emerging paradigms about rhodopsin structure and function. The successful testing of these new concepts will lead to a more accurate molecular framework to understand the function of the system under normal conditions and dysfunctions in inherited human disease.

描述（由申请人提供）：在杆光感受器细胞中存在的视紫红质分子捕获光子光子后，启动了苏ot视力。光受体视紫红蛋白的激活使一系列称为光转导的生化反应，从而导致细胞的超极化。该研究计划的长期目标是了解正常状态和患病状态下光转导的生化事件的分子机制。起点将是视紫红质的结构功能研究。该分子的重要性超出了其在光转导中的核心作用。 Rhodopsin基因是引起遗传视力障碍的突变的热点，这些突变是常染色体显性视网膜炎色素炎的主要原因，这是一种遗传性视网膜退行性疾病的异质群。尽管可用于视紫红质的丰富知识，但其作用的准确机制仍然不可用，并且光受体中引起视力障碍的基础突变的机制尚不清楚。我们的近期目标是探索有关扩展古典教条的系统的新兴想法；也就是说，多紫红蛋白的多种活性状态和将视紫红质的组织组织成二聚体簇的概念。该提案的目的是围绕理解在正常情况和患病疾病的人中的活性的基本分子原理的主题联系。在第一个目的中，我们将测试大多数研究中的隐式假设，即人类视紫红质的结构和功能与用于了解人类疾病病理学的养殖哺乳动物（牛和小鼠）的受体相似。在第二个目的中，我们将检验以下假设：受体的多个活性状态，其中至少有一种导致在变圆形突变体中引起先天性固定夜间失明的构成活性。在第三个目标中，我们将测试假定的视紫红蛋白二聚体模型，并确定受体寡聚化是否有助于导致常染色体显性视网膜色素性色素炎的视紫红质突变体的表型。需要大量的技术进步来克服研究膜蛋白的内在困难，以观察天然结构和分子细节，这些细节对于理解系统很重要。我们的建议利用了几种高分辨率生物物理方法，包括原子力显微镜，单分子力光谱和福斯特共振能量转移。这些方法与更传统的生化，生物物理和遗传学方法的结合将克服单独的传统测定法的局限性，并使我们能够直接测试有关杜鹃素结构和功能的新兴范式。这些新概念的成功测试将导致更准确的分子框架，以了解在正常条件和遗传性人类疾病中功能障碍下系统的功能。