Global Intracellular Responses to Mitophagy

项目总结 线粒体进行氧化磷酸化，为体内大多数细胞生成三磷酸腺苷。这个 受损或功能失调的线粒体的积累导致了一系列人类疾病。 有丝分裂是一种质量控制过程，它消除并回收受损的线粒体，以防止其 积累。大多数研究集中在有丝分裂缺陷如何影响有丝分裂后细胞，因为第一 发现有丝分裂基因的常染色体隐性突变可导致神经退行性疾病，如 然而，现在很明显，许多其他类型的细胞具有高水平的丝裂原活性；然而，我们 不了解有丝分裂在这些背景下的重要性或影响。例如，干细胞表现出高水平 有丝分裂的水平，在他们的一生中不断地分化，并可能将有丝分裂作为一种机制 以确保子代细胞获得健康的线粒体。为了实现这一目标，我们的发现支持有丝分裂 与细胞分裂密切相关的是一种必需的细胞器间信号激酶，它可以转移到任何一个 线粒体或中心体激活任一细胞突起。为了在未来五年内进一步开展这项工作， 这项提议将使用活体成像、遗传果蝇筛查、细胞生物学和生化方法， 转基因小鼠模型和原代干细胞回答以下问题：1)做有丝分裂缺陷 影响干细胞分裂和线粒体遗传？2)我们能识别其他吞丝分裂蛋白/基因吗？ 影响细胞分裂？3)连接有丝分裂和细胞分裂的细胞器间信号类型 当被其亚细胞定位所支配时，控制其他细胞过程？这项工作的广泛影响 将阐明为什么有丝分裂基因在其他复杂疾病中发生突变，如癌症，为深入了解 线粒体功能障碍如何影响导致神经发育和认知障碍的干细胞， 并定义细胞器之间的基本信号相互作用，以加深我们对细胞如何 在全球范围内应对功能失调的线粒体。

PROJECT SUMMARY Mitochondria perform oxidative phosphorylation to generate ATP for a majority of the cells in the body. The accumulation of damaged or dysfunctional mitochondria contribute to a wide range of human diseases. Mitophagy is a quality control process that eliminates and recycles damaged mitochondria to prevent their accumulation. A majority of studies focus on how mitophagy defects affect post-mitotic cells because the first identified autosomal recessive mutations in mitophagy genes caused neurodegenerative diseases such as Parkinson’s. However, it is now clear that many other cell types have high levels of mitophagic activity; yet, we do not understand the importance or impact of mitophagy in these contexts. For example, stem cells display high levels of mitophagy, divide continuously throughout their lifespan, and possibly use mitophagy as a mechanism to ensure daughter cells receive healthy mitochondria. Towards this goal, our findings support that mitophagy and cell division are intimately linked by a required interorganelle signaling kinase that translocates to either mitochondria or centrosomes to activate either cell process. To build upon this work within the next five years, this proposal will use live imaging, genetic drosophila screens, cell biology and biochemical approaches, transgenic mouse models, and primary stem cells to answer the following questions: 1) Do defects in mitophagy affect stem cell division and mitochondrial inheritance? 2) Can we identify other mitophagy proteins/genes that influence cell division? 3) Does the type of interorganelle signaling that connects mitophagy and cell division control other cellular processes when dictated by its subcellular localization? The broad implications of this work will elucidate why mitophagy genes are mutated in other complex diseases such as cancer, provide insight into how mitochondrial dysfunction affects stem cells contributing to neurodevelopmental and cognitive disorders, and define fundamental signaling interactions between organelles to deepen our understanding of how cells globally respond to dysfunctional mitochondria.