Study of redox regulated pathways in the mitochondrion

描述（由申请人提供）：线粒体在能量产生、防止氧化损伤和调节细胞死亡中起着关键作用。因此，线粒体功能障碍有助于广泛的肌肉和神经疾病，包括帕金森氏症、耳聋肌张力障碍综合征和利氏综合征。此外，线粒体蛋白输入缺陷与遗传性疾病之间的首次联系是在Mohr-Tranebjaerg综合征/耳聋-肌紧张性障碍综合征（MTS）患者中发现的；这是由一种小的Tim蛋白（酿酒葡萄球菌中的DDP1， Tim8）突变引起的。DDP1组装的关键参与者是Erv1蛋白，一种巯基氧化酶和Mia40。因此，DDP1组装的描述与理解耳聋肌张力障碍综合征的分子基础有关。我建议的研究重点是表征一条进入线粒体膜间空间（IMS）的途径，该途径是氧化还原调节的，是DDP1.1组装所必需的。我建议：(1)鉴定Erv1相互作用的蛋白质，包括底物和伴侣蛋白，(2)重建与Erv1、Mia40和潜在伴侣蛋白的二硫交换反应。IMS中的这一途径在过去三年中才被确定，因此，对这一重要途径及其组成部分的全面了解将有助于开发耳聋-肌张力障碍综合征和其他破坏性线粒体疾病的潜在治疗方法。此外，进口途径应该更好地表征，因为它们可能作为治疗性化合物的递送系统。最后，我提出的酵母模型研究，是符合生物化学和遗传学的，将为未来哺乳动物系统的研究提供基础，因为酵母和哺乳动物之间的进口很大程度上是保守的。这个项目对公众健康很重要，因为线粒体缺陷会导致广泛的神经退行性和肌肉疾病以及衰老。

DESCRIPTION (provided by applicant): The mitochondrion plays a key role in energy production, prevention of oxidative damage and regulation of cell death. Consequently, mitochondrial dysfunction contributes to a broad range of muscular and neural disorders, including Parkinson's, deafness-dystonia syndrome, and Leigh's syndrome. Furthermore, the first connection between a defect in mitochondrial protein import and an inherited disease was made in patients with Mohr-Tranebjaerg syndrome/deafness-dystonia syndrome (MTS); this is caused by mutations in one of the small Tim proteins (DDP1, Tim8 in S. cerevisiae). Key players in assembly of DDP1 are proteins Erv1, a sulfhydryl oxidase, and Mia40. Thus, delineation of DDP1 assembly is pertinent to understanding the molecular basis of deafness-dystonia syndrome. My proposed research centers on characterization of an import pathway into the mitochondrial intermembrane space (IMS) that is redox regulated and is required for the assembly of DDP1.1 propose (1) to identify Erv1 interacting proteins including substrates and partner proteins, and (2) to reconstitute the disulfide exchange reaction with Erv1, Mia40 and potential partner proteins. This pathway in the IMS has only been identified in the past three years and thus, a complete knowledge of this import pathway and its components would aid in development of potential treatments and therapies for deafness-dystonia syndrome and other devastating mitochondrial diseases. Additionally, import pathways should be better characterized because they might serve as delivery systems for therapeutic compounds. Lastly, my proposed studies in the model yeast, which is amenable to biochemistry and genetics, will provide the basis for future studies in mammalian systems because import is largely conserved between yeast and mammals. This project is important to public health because defective mitochondria contribute to a broad range of neurodegenerative and muscular diseases as well as aging.