The differential behavior of Prph2/Rom1 in rods and cone contributes to Prph2-associated disease heterogeneity

Prph2/Rom1 在视杆细胞和视锥细胞中的差异行为导致与 Prph2 相关的疾病异质性

• 批准号: 10701039
• 负责人: Larissa Ikelle
• 金额: $ 4.15万
• 依托单位: UNIVERSITY OF HOUSTON
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-09-28 至 2026-09-27
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10701039
• 关键词: Address; Affect; Affinity Chromatography; Animal Model; Attention; Backcrossings; Behavior; Binding; Biochemical; Bypass; Clinical; Co-Immunoprecipitations; Complex; Cone; Data; Development; Disease; Disease model; Electron Microscopy; Etiology; Exhibits; Future; Goals; Golgi Apparatus; Health; Homo; Homologous Gene; Imaging Techniques; Impairment; In Vitro; Inherited; Investigation; Knock-out; Knowledge; Leucine Zippers; Macular degeneration; Maintenance; Membrane Microdomains; Membrane Proteins; Methods; Modeling; Modification; Molecular Conformation; Morphogenesis; Mutation; Nature; Neural Retina; Outcome Assessment; Outcome Study; Pathogenesis; Pathogenicity; Pathology; Pathway interactions; Patients; Pattern; Phenotype; Photoreceptors; Process; Proteins; Psammomys; Rattus; Research; Resolution; Retina; Retinal Diseases; Retinitis Pigmentosa; Rod; Rod Outer Segments; Rodent Model; Role; Sand Rats; Severity of illness; Silicon Dioxide; Structure; Testing; Therapeutic; Three-dimensional analysis; Vertebrate Photoreceptors; cell type; conditional knockout; disease heterogeneity; disease phenotype; effective therapy; in vivo; in vivo Model; innovation; interest; macular dystrophy; microscopic imaging; mutant; overexpression; pattern dystrophies; peripherin; photoreceptor degeneration; syntaxin; therapeutically effective; trafficking

PROJECT SUMMARY Mutations in Peripherin 2 (PRPH2) account for a significant portion of inherited retinal diseases (IRD). Delineating the role of PRPH2 in photoreceptor morphogenesis and rim formation is vital to understand how mutations in a single protein could contribute to such diverse group of pathologies, ranging from retinitis pigmentosa (RP) to pattern dystrophy (PD) and macular degeneration (MD). Even patients with intrafamilial mutations can exhibit a notable degree of phenotypic variability, attesting to the complex nature in which PRPH2 functions. My objective in this application is to advance our current knowledge of the role of PRPH2 in outer segment (OS) formation in order to have a better understanding of disease pathogeneses and for future development of effective therapeutic strategies. Over the years, our lab has developed an extensive toolbox of in vitro and in vivo mutant models, and are currently exploring innovative imaging techniques to further our understanding of the role of Prph2 in OS landscape. Thus far, it has been determined that the association between Prph2 and its homologue, Rod OS Protein 1 (Rom1), contributes significantly to the phenotypic variability observed in patients and that lowering Rom1 levels could shift a sever Prph2-assocaited PD phenotype to milder RP. Furthermore, it is know that the proper function of Prph2 at the disc rim is contingent upon proper complex assembly of Prph2-oligomers and Prph2/Rom1-complexes. The central focus of this investigation is to understand how Prph2 and Rom1 function differently in rods and cones with particular interest in Prph2 homo- and Prph2/Rom1 hetero-complex formation/trafficking, and the effects of Prph2 mutations on these processes. We propose two aims to address these goals: Aim 1 will assess the role of Rom1 in cones and the mechanism by which it modulates Prph2-disease phenotypes. By eliminating or overexpressing Rom1 in Prph2-disease models, we will conduct careful biochemical, structural, and functional analyses to assess phenotypic differences, as they pertain to complex assembly and OS trafficking. Aim 2 will investigate the role of interacting partners in the differential behavior of Prph2 in rods vs cones. In order to properly traffic and function in the OS, Prph2 forms membrane microdomains to organize and house a network of proteins that are necessary/specific for the formation of the closed rims in rods and open lamellae/rims in cones. In this aim, we will identify critical Prph2 binding partners and determine how these interactions differ between rods and cones. The outcomes of these studies will elucidate the specific function of Prph2 and Rom1 in rods and cones, determine how modulating Rom1 affects disease phenotypes, and will further our understanding of the role of Prph2 in the closed rim structure in rods and the open rim structures in cones. Given the lack of effective treatments for Prph2-associated diseases, these studies are essential and bring attention to the role of Rom1 as a common disease modulator for future development of effective therapeutic strategies.

项目总结 外周蛋白2(PRPH2)基因突变是遗传性视网膜疾病(IRD)的重要原因。 阐明PRPH2在光感受器形态发生和边缘形成中的作用对于了解 一种蛋白质的突变可能导致从视网膜炎到各种不同的病理类型。 色素性(RP)到模式营养不良(PD)和黄斑变性(MD)。即使是家庭内的患者 突变可以表现出显著程度的表型变异，证明了PRPH2 功能。我在这个应用程序中的目标是促进我们目前对PRPH2在外源蛋白中的作用的了解 片段(OS)的形成，以便更好地了解疾病的发病机制，并为未来 制定有效的治疗策略。多年来，我们的实验室开发了一套广泛的工具箱 体外和体内突变模型，目前正在探索创新的成像技术，以进一步 了解Prph2在操作系统环境中的作用。到目前为止，已经确定该协会 在Prph2及其同源物Rod OS Protein 1(Rom1)之间，Rod OS Protein 1对表型有显著贡献 在患者中观察到的变异性，降低Rom1水平可以改变与Prph2相关的严重PD表型 至较温和的RP。此外，还知道Prph2在盘沿的适当功能取决于适当 Prph2-齐聚物和Prph2/Rom1-络合物的络合组装。这次调查的中心焦点是 了解Prph2和Rom1在视杆细胞和视锥细胞中的不同功能 Prph2同源和Prph2/Rom1异源复合体的形成/运输以及Prph2突变的影响 在这些过程中。我们提出了两个目标来解决这些目标：目标1将评估Rom1在 视锥细胞及其调节Prph2疾病表型的机制。通过消除或过度表达 在Prph2-疾病模型中，我们将进行仔细的生化、结构和功能分析 评估表型差异，因为它们与复杂的组装和OS贩运有关。AIM 2将调查 相互作用伙伴在Prph2在视杆细胞和视锥细胞中的不同行为中的作用。为了使交通正常进行 和在OS中的功能，Prph2形成膜微域来组织和容纳蛋白质网络，该网络 对于形成杆中的闭合轮缘和圆锥体中的开放片层/轮缘是必要的/专用的。在这个目标中， 我们将确定关键的Prph2结合伙伴，并确定杆和杆之间的这些相互作用有何不同 圆锥体。这些研究的结果将阐明Prph2和Rom1在视杆细胞和视锥细胞中的特定功能， 确定调节Rom1如何影响疾病表型，并将加深我们对Rom1的作用的理解 Prph2在杆状结构中为闭合环结构，在圆锥体中为开环结构。鉴于缺乏有效的 对于Prph2相关疾病的治疗，这些研究是必不可少的，并引起人们对Rom1作为 为未来制定有效的治疗策略提供了一种常见的疾病调节剂。