Mitochondrial Quality Control by Drp1

摘要 线粒体通过氧化磷酸化主动生成ATP，并不断经历高水平的 氧化应激。线粒体的溶酶体降解是抑制堆积的关键质量控制 线粒体受损的可能性。了解线粒体质量控制是至关重要和紧迫的，因为它的缺陷 与许多神经疾病有关，如阿尔茨海默氏症、帕金森氏病和 肌萎缩侧索硬化症。我们的初步数据让我们假设，大脑特有的溶酶体- 相关的Drp1 GTPase亚型，称为lysoDrp1，通过以下方式促进线粒体向溶酶体的运输 增加了这两个细胞器之间的距离。在这项拟议的调查中，我们将测试这一点 假设有两个具体的目的。在第一个目标中，我们将确定lysoDrp1如何将线粒体运送到 溶酶体(1.1)，GTP如何调节LysoDrp1(1.2)，以及是什么将LysoDrp1招募到溶酶体(1.3)。在 第二个目的，我们将确定LysoDrp1在神经元线粒体周转中的作用(2.1)，即 LysoDrp1-神经元能量代谢的质量控制(2.2)，以及LysoDrp1对 神经元存活率(2.3)。为了成功地实现这些目标，我们将采用创新的方法，包括 由CRISPR/Cas9产生的lysoDrp1特异性小鼠基因敲除，CRISPR/Cas9是一种用于转运 线粒体到溶酶体，以及由单一的、特定的Drp1亚型重组的Drp1基因敲除细胞。这部作品 将对将线粒体质量控制的机制信息转化为 人类疾病的治疗干预。

Abstract Mitochondria actively generate ATP via oxidative phosphorylation and constantly undergo high levels of oxidative stress. Lysosomal degradation of mitochondria is a key quality control that inhibits the accumulation of mitochondrial damage. Understanding mitochondrial quality control is critical and urgent because its defects have been linked to many neurological disorders such as Alzheimer's disease, Parkinson's disease and amyotrophic lateral sclerosis. Our preliminary data led us to hypothesize that a brain-specific, lysosome- associated isoform of Drp1 GTPase, termed lysoDrp1, enhances transport of mitochondria to lysosomes by increasing the proximity between these two organelles. In this proposed investigation, we will test this hypothesis in two specific aims. In the first aim, we will determine how lysoDrp1 delivers mitochondria into lysosomes (1.1), how GTP regulates lysoDrp1 (1.2), and what recruits lysoDrp1 to lysosomes (1.3). In the second aim, we will determine the function of lysoDrp1 in mitochondrial turnover in neurons (2.1), the role of lysoDrp1-meidated quality control for energy metabolism in neurons (2.2), and the impact of lysoDrp1 on the survival of neurons (2.3). To successfully accomplish these aims, we will use innovative approaches including lysoDrp1-specific mouse knockout generated by CRISPR/Cas9, a fluorescent biosensor for the transport of mitochondria to lysosomes and Drp1-knockout cells reconstituted with single, specific Drp1 isoforms. This work will have a significant impact on translating the mechanistic information of mitochondrial quality control into therapeutic interventions for human diseases.