Characterizing new genes that govern mitochondrial function in the axon

摘要 线粒体是神经元健康的组成部分。随后，线粒体功能的缺陷导致 大量神经退行性疾病，其中轴突功能障碍和死亡通常先于细胞体 死亡然而，我们对线粒体生物发生的基础生物学知之甚少， 形态学变化、运输或体内轴突的功能。发现和表征新的 调节轴突中线粒体生物学基本方面的分子可能会“打开"完全 神经退行性疾病的新研究方向在这项提案中，我们的目标是发现新的监管机构， 使用新的高通量无偏正向遗传筛选研究轴突中线粒体的功能 这是最近在实验室开发的一种方法。这种方法使我们能够分析线粒体形态， 数量和分布在轴突与前所未有的单轴突和单轴突的分辨率， vivo.新发现的线粒体基因将使用我们现有的一系列新工具进行表征。 优化了果蝇的线粒体研究，我们将精确地确定线粒体如何 在体内已经改变了生理学。我们还将从遗传学上确定新的线粒体调节 基因在确定的途径中起作用以控制线粒体的维持。考虑到线粒体健康 功能与神经退行性疾病密切相关，很可能这些基因中的一些 将在神经变性中起因果和/或辅助作用。因此，我们还将调查 这些新的线粒体相关分子在多巴胺神经元中具有恶化的表型， 因为它们在帕金森病（PD）中选择性退化，帕金森病是一种线粒体功能障碍 氧化应激被认为在疾病进展中起着重要作用。功能保守性 这些新的分子将在体外哺乳动物神经元中进行检测。这一努力代表（对 据我们所知）第一次高通过前向遗传筛选所需的分子， 线粒体向轴突的运输和维持。因此，大量新的神经元调节因子 在神经疾病中具有潜在作用的线粒体尚待鉴定。

Abstract Mitochondria are integral to neuronal health. Subsequently, deficits in mitochondrial function contribute to a wealth of neurodegenerative diseases, where axonal dysfunction and die back usually precedes cell body demise. However, we know relatively little about the basic biology of mitochondrial biogenesis, morphological changes, transport, or function in axons in vivo. The discovery and characterization of new molecules regulating fundamental aspects of mitochondrial biology in axons may `open the door' to entirely new lines of research in neurodegenerative disease. In this proposal we aim to discover new regulators of mitochondria function in the axon using a novel and high throughput unbiased forward genetic screening approach recently developed in the lab. This approach allows us to assay mitochondrial morphology, number, and distribution in axons with unprecedented single axon and single mitochondrion resolution in vivo. Newly identified mitochondrial genes will then be characterized using an array of new tools we have optimized for mitochondrial studies in Drosophila, and we will determine precisely how mitochondrial physiology has been altered in vivo. We will also genetically determine how novel mitochondrial regulating genes function in defined pathways to control mitochondrial maintenance. Given that mitochondrial health and function is tightly correlated with neurodegenerative disease, it is likely that a number of these genes will play causal and/or accessory roles in neurodegeneration. We will therefore also investigate whether these novel mitochondria associated molecules have an exacerbated phenotype in dopamine neurons, since they selectively degenerate in Parkinson's disease (PD), a condition where mitochondrial dysfunction and oxidative stress is thought to play a fundamental role in disease progression. Functional conservation of these new molecules will then be assayed in mammalian neurons in vitro. This effort represents (to the best of our knowledge) the first high through forward genetic screen for molecules required for mitochondrial transport to and maintenance in axons. Thus a wealth of novel regulators of neuronal mitochondria, which have potential roles in neurological disease, await identification.