Pathogenesis of Mitochondrial Retina Disease

线粒体视网膜疾病的发病机制

基本信息

批准号：
10709868
负责人：
Nathaniel Kevin Mullin
金额：
$ 3.83万
依托单位：
UNIVERSITY OF IOWA
依托单位国家：
美国
项目类别：
财政年份：
2022
资助国家：
美国
起止时间：
2022-08-10 至 2024-08-09
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10709868
关键词：
Affect Alleles Blindness Cell Line Cells Cellular Assay Choroid Chromatin Clinical Collection Data Development Diabetes Mellitus Disease Dyes Endothelial Cells Environment Eye Functional disorder Genes Genetic Genetic Diseases Genetic Models Genetic study Genome Goals In Vitro Individual Inherited Knowledge Libraries MELAS Syndrome Measures Mediating Metabolic Metabolic Pathway Metabolic dysfunction Metabolism Mitochondria Mitochondrial Diseases Mitochondrial Proteins Mitosis Mutation NADH Neural Retina Nuclear Nutrient Outcome Oxidation-Reduction Pathogenesis Pathogenicity Patients Pattern Phenotype Physicians Pigment Epithelium Population Positioning Attribute Production Research Rest Retina Retinal Diseases Retinal Dystrophy Scientist Severity of illness Structure of retinal pigment epithelium Syndrome System TNFSF15 gene Tissue Donors Tissues Transposase Variant career cell type clinical phenotype deafness disease-causing mutation heteroplasmy high throughput screening induced pluripotent stem cell inhibitor insight leucine-tRNA metabolic phenotype metabolic profile mitochondrial genome mutant neural new therapeutic target novel strategies patient subsets programs retinal damage segregation targeted treatment

项目摘要

PROJECT SUMMARY The mitochondrial m.3243A>G variant is a common cause of genetic mitochondrial disease that causes dysfunction of the retina and other tissues. Due to the high copy number of the mitochondrial genome per cell, this variant exists in cells across a broad range of proportions. How the proportion of mutant to wildtype m.3243 allele in any given cell, tissue, or individual relates to the cellular and clinical phenotype is not well understood. In the proposed research program, we will identify how this variant causes metabolic dysfunction in ocular cells and in which cell types the variant is preferentially distributed in the retina and underlying metabolic support tissue during development. Clinical observation has implicated the retinal pigment epithelium (RPE) as the driver of retinal dystrophy in m.3243A>G disease. Using induced pluripotent stem cells (iPSCs) derived from patients carrying m.3243A>G, we will generate RPE containing various controlled proportions of the variant. We will then subject these cells to a high throughput assay to determine derangement of the normal metabolic program of RPE. This approach will allow us to determine how increasing levels of m.3243A>G proportion in RPE impacts mitochondrial and metabolic function. We and others have previously observed that the m.3243A>G variant segregates non-randomly during the development of the retina, choroid, and other tissues. Specifically, we have observed in primary ocular tissue that the choroidal endothelial cells (CEC) that supply nutrients to the RPE and outer retina select against m.3243A>G. In the proposed research program, we will generate neural retina and CECs from patient iPSCs and measure the proportion of m.3243A>G to determine if and how these cells are able to select against the pathogenic variant during in vitro development. When successful, these studies will advance knowledge of the pathogenicity of the m.3243A>G variant in the retina. Further understanding the cell type-specific segregation of this mitochondrial variant and the specific metabolic dysfunctions it causes may lead to novel therapeutic targets for the treatment of this and other retinal diseases caused by mutations in mitochondrial genes.

项目概要线粒体 m.3243A>G 变异是遗传性线粒体疾病的常见原因，可导致视网膜和其他组织的功能障碍。由于每个细胞线粒体基因组的拷贝数很高，这种变异存在于各种比例的细胞中。突变体与野生型的比例如何 m.3243 等位基因在任何给定细胞、组织或个体中与细胞和临床表型的关系尚不明确明白了。在拟议的研究计划中，我们将确定这种变异如何导致代谢功能障碍在眼细胞中，以及该变体优先分布在视网膜和底层的细胞类型中发育过程中的代谢支持组织。临床观察表明视网膜色素上皮 (RPE) 是视网膜营养不良的驱动因素 m.3243A>G疾病。使用源自携带 m.3243A>G 的患者的诱导多能干细胞 (iPSC)，我们将生成包含各种受控比例的变体的 RPE。然后我们将对这些细胞进行处理进行高通量测定以确定 RPE 正常代谢程序的紊乱。这种做法将使我们能够确定 RPE 中 m.3243A>G 比例水平的增加如何影响线粒体和代谢功能。我们和其他人之前观察到 m.3243A>G 变体在视网膜、脉络膜和其他组织的发育。具体来说，我们在初级眼组织中观察到向 RPE 和外视网膜提供营养的脉络膜内皮细胞 (CEC) 选择反对 m.3243A>G。在拟议的研究计划中，我们将从患者 iPSC 中生成神经视网膜和 CEC 并测量 m.3243A>G 的比例，以确定这些细胞是否以及如何能够针对体外发育过程中的致病变异。如果成功，这些研究将增进对 m.3243A>G 变体致病性的了解视网膜。进一步了解这种线粒体变体的细胞类型特异性分离以及特定的它引起的代谢功能障碍可能会导致治疗这种视网膜和其他视网膜的新治疗靶点由线粒体基因突变引起的疾病。