Mitochondrial DNA Replisome: Mechanism, Structure and Physiology

描述(申请人提供)：摘要：拟议工作的长期目标是阐明动物线粒体中DNA复制的机制，以及它与线粒体突变和人类疾病的关系。采用生物化学、结构生物学和分子遗传学相结合的方法研究线粒体复制体的机制、结构和生理学，重点研究复制型DNA解旋酶和线粒体单链DNA结合蛋白。结合我们等人对线粒体中的关键复制酶DNA聚合酶3的广泛研究，我们扩大了先前的研究范围，以研究线粒体DNA复制叉处蛋白质的组装和功能，并探索线粒体DNA在体内和体外的复制模式。线粒体是动物体内产生能量的细胞器，线粒体的功能几乎影响细胞功能的方方面面。因此，线粒体在人类健康中发挥着重要作用，同样，线粒体功能障碍与人类疾病有着错综复杂的联系。线粒体功能障碍涉及广泛的神经系统疾病、代谢性疾病、肌肉营养不良和肾病，以及广泛的命名疾病。线粒体生物发生缺陷导致线粒体DNA突变、耗竭和缺失综合征，从而导致线粒体丧失和随后的细胞功能。线粒体遗传病的流行以及最近对抗病毒和抗微生物药物对线粒体毒性的认识，迫切需要深入了解线粒体DNA复制装置的结构和功能。 公共卫生相关性：叙述：各种慢性、与年龄相关的疾病的一个共同特征是细胞产生能量的能力崩溃或障碍。细胞能量产生的中心是线粒体，这是一种在多种代谢过程中发挥关键作用的细胞器，其功能障碍与许多疾病直接相关，包括那些在老龄化人口中表现最明显的疾病。因此，清楚地了解线粒体的生物发生和能量产生，以及在常见疾病状态下这些过程是如何解除管制的，对于有效(和经济地)治疗它们是至关重要的。

DESCRIPTION (provided by applicant): Abstract: The long-term objective of the proposed work is the elucidation of the mechanism of DNA replication in animal mitochondria, and its relationship to mitochondrial mutagenesis and human disease. A combined approach of current methods in biochemistry, structural biology and molecular genetics will be pursued to study the mechanism, structure and physiology of the mitochondrial replisome, with a focus on the replicative DNA helicase and the mitochondrial single-stranded DNA-binding protein. In combination with the extensive studies by us and others on the key replicative enzyme in mitochondria, DNA polymerase 3, we expand the scope of prior research to study the assembly and function of proteins at the mitochondrial DNA replication fork, and to probe the modes of mitochondrial DNA replication in vivo and in vitro. Mitochondria are the energy-producing organelle in animals and mitochondrial function impacts nearly every aspect of cellular function. Thus, mitochondria play a major role in human health and likewise, mitochondrial dysfunction is intricately associated with human disease. Mitochondrial dysfunction is implicated in a wide range of neurological diseases, in metabolic diseases, in muscular dystrophies and nephropathies, and in a broad spectrum of named disorders. Defects in mitochondrial biogenesis lead to mitochondrial DNA mutation, depletion and deletion syndromes that result in loss of mitochondrial and subsequent cellular function. The prevalence of mitochondrial genetic disease and recent recognition of the mitochondrial toxicity of antiviral and antimicrobial drugs the critical need for an in-depth understanding of the structure and functions of the mitochondrial DNA replication apparatus. PUBLIC HEALTH RELEVANCE: Narrative: A common feature in diverse chronic, age-related diseases is a breakdown or disturbance in the cell's ability to produce energy. Central to the cellular energy production is the mitochondrion, an organelle that plays a crucial role in multiple metabolic processes, and whose dysfunction is linked directly to many pathologies, including those most represented in an aging population. Therefore, a clear understanding of mitochondrial biogenesis and energy production and how these processes are deregulated in common disease states, is essential to treating them effectively (and economically).