Genetic modifiers of Cep290-mediated retinal degeneration

Cep290介导的视网膜变性的遗传修饰剂

• 批准号: 9759929
• 负责人: Michael G Anderson
• 金额: $ 19.06万
• 依托单位: UNIVERSITY OF IOWA
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-09-01 至 2021-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9759929
• 关键词: Age; Antisense Oligonucleotides; Basic Science; Biological; Biological Process; Biology; Blindness; CAST/EiJ Mouse; CRISPR/Cas technology; Carrier Proteins; Cessation of life; Chromosomes, Human, Pair 12; Cilia; Clinical; Clinical Sciences; Complement; Data; Disease; Elements; Embryo; Exhibits; Face; Female; Fibroblasts; Functional disorder; Gene Expression Regulation; Generations; Genes; Genetic; Genetic Crosses; Genetic study; Genome; Genotype; Goals; Inbreeding; Inherited; Leber' s amaurosis; Life; Light; Lod Score; Masks; Measures; Mediating; MicroRNAs; Molecular; Mus; Mutant Strains Mice; Mutate; Mutation; Optical Coherence Tomography; Parents; Pathologic Nystagmus; Phenotype; Photoreceptors; Physiological; Play; Proteins; Quantitative Trait Loci; Resources; Retina; Retinal; Retinal Degeneration; Retinal Diseases; Role; Severities; Severity of illness; Testing; Therapeutic; Thick; Tissue-Specific Gene Expression; Tissues; Western Blotting; Work; base; bioinformatics resource; causal variant; clinically significant; cohort; cytotoxic; dosage; experimental study; gene therapy; genome-wide; imprint; insight; loss of function; male; mouse model; overexpression; physical mapping; power analysis; protein transport; public health relevance; sex; stem; therapeutic target; transcriptome sequencing

Abstract Leber congenital amaurosis (LCA) is a group of inherited retinal degenerative diseases characterized by nystagmus and blindness that typically manifest in the first year of life. As with several retinal degenerative diseases, many forms of LCA involve dysfunction of photoreceptor cilia. Mutations in the CEP290 gene are the most common cause of LCA, implicating CEP290 as a major contributor to the disease. CEP290 encodes a large protein proposed to regulate protein transport through the photoreceptor connecting cilium spanning the inner and outer segments. Using a mouse model of CEP290-mediated LCA, the rd16 mouse, we have found that the relative severity of Cep290 phenotypes in mice is highly sensitive to genetic background. Here, we propose experiments using mice that take advantage of this background sensitivity to identify genetic modifiers of Cep290-mediated retinal degeneration. Identification of these modifiers has both basic, and clinical, significance. From a basic biology perspective, studies of genetic modifiers can uncover basic biological functions of CEP290, photoreceptor cilia, and their gestalt contributions to retinal disease in a physiologic context. From a clinical perspective, identification of genetic modifiers offers an opportunity to identify therapeutic surrogates. The premise for our current proposal, its feasibility, and evidence of our ability to conduct quantitative modifier studies of retinal degeneration all stem from a relatively large body of recent work. We have performed large genetic crosses with mice and identified quantitative trait loci modifying retinal disease severity of mice homozygous for the Cep290rd16 mutation. Among regions of the genome identified as particularly important, our current proposal focuses on the Modifier of retinal degeneration quantitative trait locus 1 (Mrdq1) located on mouse chromosome 12. A unique feature of this modifier that has aided our ability to identify its molecular basis is that it shows imprinting—its influence varies according to parent-of-origin. Using physical mapping in combination with a study of retinal expressed genes that are imprinted, we have identified an overt mutation within a previously unstudied microRNA that is highly likely to be the causative mutation. Experiments of this proposal describe the work to stringently confirm that we have identified the precise mutation underlying the Mrdq1 modifier (Specific Aim 1), and begin to study its mechanisms of action through identification of downstream targets of the microRNA present in photoreceptors. At completion, we expect this work to have impact on CEP290-mediated LCA, as well as promote a better understanding of how two understudied phenomena, gene regulation via microRNAs and imprinting, influence retinal disease.

抽象的 莱伯先天性黑蒙（LCA）是一组遗传性视网膜退行性疾病，其特征是 眼球震颤和失明通常出现在生命的第一年，与一些视网膜退行性病变一样。 许多形式的 LCA 与光感受器纤毛功能障碍有关。CEP290 基因突变。 LCA 的最常见原因，表明 CEP290 是该疾病的主要贡献者。 大蛋白质被提议通过连接纤毛的光感受器调节蛋白质运输 使用 CEP290 介导的 LCA 小鼠模型（rd16 小鼠），我们发现了内节和外节。 小鼠中 Cep290 表型的相对严重程度对遗传背景高度敏感。 实验建议使用利用这种背景敏感性的小鼠来识别遗传修饰剂 Cep290 介导的视网膜变性的鉴定具有基础和临床两个方面。 从基础生物学的角度来看，基因修饰剂的研究可以揭示基础生物学的意义。 CEP290、光感受器纤毛的功能及其在生理学中对视网膜疾病的格式塔贡献 从临床角度来看，遗传修饰物的识别提供了识别的机会。 我们当前提议的前提、其可行性以及我们能力的证据。 对视网膜变性进行修饰研究均源于近期相对较大的研究成果 我们与小鼠进行了大规模的遗传杂交，并确定了改变视网膜的数量性状位点。 Cep290rd16 突变纯合小鼠的疾病严重程度被确定为基因组区域。 特别重要的是，我们目前的提案重点关注视网膜变性数量性状的修饰因子 位点 1 (Mrdq1) 位于小鼠 12 号染色体上。该修饰符的独特功能有助于我们的能力 识别其分子基础是它显示出印记——其影响因亲本而异。 使用物理绘图结合对视网膜表达的印记基因的研究，我们得到了 在之前未研究过的 microRNA 中发现了一个明显的突变，该突变极有可能是致病原因 该提案的实验描述了严格确认我们已经识别出的工作。 Mrdq1修饰剂的精确突变（具体目标1），并开始研究其作用机制 通过识别光感受器中存在的 microRNA 的下游靶标，我们完成了这项工作。 期望这项工作对 CEP290 介导的 LCA 产生影响，并促进更好地理解如何 通过 microRNA 进行基因调控和印记这两种尚未得到研究的现象会影响视网膜疾病。