Modulation of ATP synthesis in mitochondrial disorders

描述（由申请人提供）： 作为一名在临床神经学和基础科学方面受过训练的研究人员，我的主要科学目标是更好地了解这组疾病的致病机制，并确定治疗它们的策略。我的主要科学职业目标是为线粒体疾病领域做出新颖而重要的贡献，并满足成为着名学术机构终身教职员工的要求。我相信，威尔医学院的神经病学和神经科学系是一个理想的环境来开展我的工作，实现我的职业目标，因为它提供了一个肥沃的土壤，通过允许与一流的科学家在三个机构的组织，包括康奈尔大学，纪念斯隆·凯特林和洛克菲勒大学的互动，科学的成长。这项建议的范围有两个方面。首先，调节线粒体ATP合成的综合征NARP（神经共济失调和视网膜色素变性）引起的突变的mtDNA编码的ATP酶6（A6）。第二，建立反映NARP特征的细胞和动物模型。这些模型将用于研究体内线粒体疾病的致病机制，并测试治疗方法。 目的1：NARP细胞产生更多的自由基。线粒体呼吸链可能由于损伤或抑制而有缺陷，抗氧化剂可以改善NARP胞质杂交细胞中的ATP合成。我们将定义呼吸链功能障碍的机制，并测试抗氧化剂在直接来自NARP患者的细胞中的作用。 目标二：我们发现，野生型A6蛋白的表达从细胞核异位提高线粒体ATP合成在胞质杂交模型的NARP。目的是评估A6的异位表达是否会改善患者来源的细胞中的ATP合成，以及这种方法是否可以具有治疗用途。 目的3：没有NARP的动物模型。外源mtDNA不能转移到线粒体中产生NARP的转基因模型。我们将测试两种替代策略来产生重现NARP的生化和临床缺陷的突变体：a）通过从靶向正常线粒体的突变体A6的细胞核的异位表达; B）通过在与A6相互作用的关键位点处的细胞核编码的线粒体蛋白ATP酶亚基C中引入突变。

DESCRIPTION (provided by applicant): As a researcher trained in clinical neurology and basic science with a primary interests in the field of mitochondrial disorders, my principal scientific goal is to better understand the pathogenic mechanisms of this group of diseases and to identify strategies to treat them. My main scientific career goals are to make novel and important contributions to the field of mitochondrial disorders and to satisfy the requirements to become a tenured faculty member in a prestigious academic institution. I believe that the Department of Neurology and Neuroscience at the Weill medical College is an ideal environment to conduct my work and to fulfill my career goals because it provides a fertile ground for scientific growth by allowing interactions with topnotch scientists within the tri-institutional organization that includes Cornell University, Memorial Sloan Kettering, and Rockefeller University. The scope of this proposal is twofold. First, to modulate mitochondrial ATP synthesis in the syndrome NARP (neuropathy ataxia and retinitis pigmentosa) caused by mutations in the mtDNA encoded ATPase 6 (A6). Second, to develop cellular and animal models recapitulating the features of NARP. Such models will serve to investigate in vivo the pathogenic mechanisms underlying mitochondrial disorders and to test therapeutic approaches. Aim 1: NARP cells generate increased free radicals. The mitochondrial respiratory chain is defective presumably due to damage or inhibition and ATP synthesis in NARP cybrid cells can be improved by antioxidants. We will define the mechanisms underlying the respiratory chain dysfunction and test the effects of antioxidants in cells directly derived from NARP patients. Aim 2: We showed that the expression of a wild type A6 protein allotopically from the nucleus improved mitochondrial ATP synthesis in a cybrid model of NARP. The goal is to assess whether allotopic expression of A6 will improve ATP synthesis in patient-derived cells and whether this approach can have a therapeutic use. Aim 3: There are no animal models of NARP. Exogenous mtDNA cannot be transferred into mitochondria to generate transgenic models of NARP. We will test two alternative strategies to generate mutants that recapitulate the biochemical and clinical defects of NARP: a) By allotopic expression from the nucleus of a mutant A6 targeted to normal mitochondria; b) By introducing mutations in a nuclear-encoded mitochondrial protein, ATPase subunit C, at crucial sites of interaction with A6.