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 Leber先天性弹药（LCA）是一组遗传性残留退化性疾病，其特征是 眼球震颤和失明通常在生命的第一年中表现出来。与几个永久退化 疾病，许多形式的LCA涉及光感受器纤毛功能障碍。 CEP290基因中的突变是 LCA的最常见原因，隐含的CEP290是该疾病的主要因素。 CEP290编码a 大型蛋白质提出了通过连接纤毛的光感受器调节蛋白质转运的大蛋白 内部和外部细分市场。使用CEP290介导的LCA的鼠标模型RD16鼠标，我们发现了 小鼠中CEP290表型的相对严重程度对遗传背景高度敏感。在这里，我们 使用利用这种背景灵敏度的小鼠进行的建议实验来识别遗传修饰符 CEP290介导的视网膜变性。这些修饰符的识别具有基本和临床 从基本的生物学角度来看，遗传修饰剂的研究可以发现基本的生物学 CEP290，光感受器纤毛的功能及其对生理疾病的残留疾病的贡献 语境。从临床角度来看，遗传修饰剂的识别提供了一个机会来识别 治疗性代理。我们当前建议的前提，其可行性以及我们能力的证据 进行剩余变性的定量修饰剂研究均源于近期相对较大的身体 工作。我们已经与小鼠进行了大遗传交叉，并确定了定量性状位点修饰了视网膜 CEP290RD16突变的纯合小鼠的疾病严重程度。在被确定为 尤其重要的是，我们当前的提议着重于永久性变性定量性状的修饰符 位点1（MRDQ1）位于小鼠染色体12上。该修饰符的独特功能有助于我们的能力 确定其分子基础是它显示出印迹 - 它会根据原生子的父母影响变化。 将物理映射与对视网膜表达的基因的研究结合使用，我们有 确定了先前未研究的microRNA中的明显突变，这很可能是病因 突变。该提案的实验描述了工作，以严格确认我们已经确定了 MRDQ1修饰符（特定目标1）的精确突变，并开始研究其作用机理 通过鉴定光感受器中存在的microRNA的下游靶标。完成后，我们 期望这项工作会对CEP290介导的LCA产生影响，并更好地了解如何了解 两种理解现象，通过microRNA调节基因调节和印记会影响残留疾病。