Cilia Assembly and Transport in Photoreceptor Cells

感光细胞中纤毛的组装和运输

• 批准号: 9134153
• 负责人: Brian D Perkins
• 金额: $ 45.11万
• 依托单位: CLEVELAND CLINIC LERNER COM-CWRU
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-08-01 至 2018-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9134153
• 关键词: Address; Adult; Alleles; Amino Acids; Anatomy; Apical; Bardet-Biedl Syndrome; Binding; Biological Models; Blindness; Cells; Cilia; Clinical; Complex; DNA Sequence Alteration; Data; Defect; Disease; Docking; Dynein ATPase; Electron Microscopy; Electrons; Embryo; Gene Components; Gene Expression; Genes; Genetic; Goals; Guanosine Triphosphate Phosphohydrolases; Human; Individual; Joubert syndrome; Kidney Diseases; Lead; Link; Location; Maintenance; Mental Retardation; Microscopic; Microtubules; Modeling; Molecular; Mutation; Organelles; Pathology; Pathway interactions; Pattern; Phenotype; Photoreceptors; Polydactyly; Population; Positioning Attribute; Process; Proteins; Reagent; Regulation; Retina; Retinal; Retinal Degeneration; Retinal Diseases; Retinal Dystrophy; Role; Side; Signal Pathway; Signal Transduction; Site; Situs Inversus; Stereotyping; Structure; Surface; System; TNFRSF5 gene; Techniques; Testing; Tissues; Transgenic Organisms; Vertebrate Photoreceptors; Vertebrates; Zebrafish; base; ciliopathy; cilium biogenesis; dynactin; hereditary blindness; kinetosome; light microscopy; loss of function; migration; mutant; novel; null mutation; photoreceptor degeneration; planar cell polarity; protein transport; research study; retinal damage; therapy development; tool; trafficking

DESCRIPTION (provided by applicant): The long-term goal of this project is to understand the molecular basis of cilia formation and maintenance in vertebrate photoreceptor cells. In vertebrates, the assembly and maintenance of photoreceptor outer segments begins with the formation of a connecting cilium. The connecting cilium contains a microtubule- based axoneme that is anchored to the apical inner segment by a basal body. Cilia formation begins with the docking of basal bodies at the apical surface of the inner segment. Genetic mutations disrupting the assembly, structure, or function of basal bodies and/or cilia result in a spectrum of diseases known as ciliopathies. These multisyndromic disorders often present with retinal degeneration, kidney disease, mental retardation, and polydactyly. In the current application, we will utilize loss-of-function strategies in zebrafish to investigate the mechanisms controlling basal body localization. In Specific Aim 1, we will test the hypothesis that the dynein/dynactin complex regulates the apical transport of basal bodies preceding cilia formation by examining zebrafish mutants in dynein and the p150 and p50 subunits of dynactin. In Specific Aim 2, we provide preliminary evidence that basal bodies show a highly polarized arrangement within the adult zebrafish retina. We will directly test the hypothesis that the PCP pathway regulates this patterning and is essential for photoreceptor survival. In Specific Aim 3, we will examine zebrafish carrying null mutations in the Joubert Syndrome gene arl13b for retinal phenotypes. Proposed experiments will also test the requirement of the GTPase domain and a ciliary-targeting sequence RVxPx for Arl13b function. We will also test arl13b for functional interactions with Bardet-Biedl Syndrome (BBS) genes, and components of the PCP pathway. These interactions will identify potential second-site modifiers that enhance expression of photoreceptor phenotypes. The results of these studies will reveal novel mechanisms required for basal body placement prior to cilia formation and to identify novel genetic interactions that influence hereditary blindness.

描述（由申请人提供）：该项目的长期目标是了解脊椎动物感光细胞中纤毛形成和维持的分子基础。在脊椎动物中，光感受器外部段的组装和维护始于形成连接纤毛。连接的纤毛包含一个基于微管的轴突，该轴突由基底体固定在顶端内部段。纤毛形成始于内部段顶部表面基底体的对接。基础体和/或纤毛的组装，结构或功能的基因突变导致多种疾病被称为纤毛病。这些多种疾病通常出现视网膜变性，肾脏疾病，智力低下和多性疾病。在当前应用中，我们将利用斑马鱼中的功能丧失策略来研究控制基础身体定位的机制。在特定的目标1中，我们将测试以下假设：Dynein/dynactin复合物通过检查纤毛形成之前的基底体的顶端转运，通过检查动力蛋白中的斑马鱼突变体以及Dynactin的P150和P50亚基。在特定的目标2中，我们提供了初步证据，表明基底体在成年斑马鱼视网膜中显示出高度极化的布置。我们将直接检验以下假设：PCP途径调节了这种模式，对于感光体存活至关重要。在特定的目标3中，我们将检查斑马鱼在乔伯特综合征基因ARL13B中用于视网膜表型中的无效突变。提出的实验还将测试ARL13B函数的GTPase域和睫状靶向序列RVXPX的需求。我们还将测试ARL13B与Bardet-Biedl综合征（BBS）基因以及PCP途径的组成部分的功能相互作用。这些相互作用将确定潜在的第二位修饰符，以增强光感受器表型的表达。这些研究的结果将揭示在纤毛形成之前基础身体所需的新型机制，并确定影响遗传失明的新型遗传相互作用。