The role of Rab1 GTPase and its activators in selective autophagy and neurodegenerative disease

Rab1 GTPase 及其激活剂在选择性自噬和神经退行性疾病中的作用

• 批准号: 9225579
• 负责人: Nava Segev
• 金额: $ 19.99万
• 依托单位: UNIVERSITY OF ILLINOIS AT CHICAGO
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-09-30 至 2018-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9225579
• 关键词: Affect; Alzheimer' s Disease; Amino Acids; Autophagocytosis; Cause of Death; Cell Line; Cell Survival; Cells; Complex; Cytoplasmic Granules; Cytoplasmic Protein; Disease; Endoplasmic Reticulum; Future; Generic Drugs; Goals; Guanosine Triphosphate Phosphohydrolases; Homologous Gene; Human; Human Cell Line; Integral Membrane Protein; Knock-in; Knock-out; Left; Lysosomes; Mammalian Cell; Membrane; Membrane Proteins; Mission; Mutate; Mutation; National Institute of Neurological Disorders and Stroke; Nerve Degeneration; Neurodegenerative Disorders; Normal Cell; Parkinson Disease; Pathway interactions; Pharmaceutical Preparations; Pharmacotherapy; Play; Process; Proteins; Quality Control; Quality of life; Recycling; Regulation; Research; Role; Small Interfering RNA; Stress; TRAPP transport protein particle; United States; Yeasts; abstracting; age related; alpha synuclein; base; design; knock-down; mutant; neuron loss; novel; overexpression; paralogous gene; protein aggregate; protein complex; rab GTP-Binding Proteins; research study; therapeutic target; tool; trafficking; tumorigenesis

Abstract Age-related neurodegenerative diseases (ND), which affect the lives of millions of people, are caused by a progressive loss of neuronal function. This loss is associated with the accumulation of aggregated proteins, such as α-synuclein in Parkinson's disease and APP in Alzheimer's disease. The pathogenic mechanisms underling these diseases, for which currently there are no cures, are not fully understood. Autophagy, a cellular recycling pathway, shuttles excess and damaged cellular components to the lysosome for degradation. We propose that constitutive selective autophagy pathways clear ND-related protein aggregates. In mammalian cells, autophagy has been extensively studied under stress conditions, but almost nothing is known about constitutive selective autophagy processes or their regulation in human cells. Here, we propose to extend our recent studies in yeast about two types of constitutive selective autophagy pathways and their regulation by the Rab1 yeast homolog, Ypt1, to human cells. Rab1 GTPase was implicated in ND and its activation was proposed to inhibit accumulation of ND-related aggregates. However, Rab1 regulates both secretion and autophagy and it is not clear through which process its activation affects ND. Moreover, Rab1 activation in secretion was implicated in oncogenesis. Thus, to elucidate through which process Rab1 affects ND, it is crucial to separate its functions in secretion and autophagy. In yeast, we succeeded in separating the functions of Ypt1 in secretion and autophagy using two approaches: generating autophagy-specific Ypt1 mutations and characterizing autophagy-specific Ypt1 activators. These activators stimulate Ypt1 in two constitutive selective autophagy pathways: clearance of excess membrane proteins and clearance of cytoplasmic protein complexes. Because all the players are conserved from yeast to human cells, we propose to determine whether our findings pertain to human cells. In Aim 1, we will attempt to generate autophagy-specific Rab1 mutations and in Aims 2-3, we will determine whether autophagy-selective activators stimulate Rab1 in two distinct constitutive selective autophagy pathways. If successful, these tools will be used in future experiments to determine whether autophagy- specific Rab1 modulation affects clearance of ND-related protein aggregates. Achieving the goals of this proposal and the future experiments would provide a novel regulation paradigm for clearance of ND-related protein aggregates. Moreover, identification of Rab1 regulators specific for constitutive selective autophagy would provide novel ND therapeutic targets, in line with the missions of the National Institute of Neurological Disorders and Stroke.

抽象的 影响数百万人生活的与年龄相关的神经退行性疾病（ND）是 由神经元功能的进行性丧失引起。这种损失与积累有关 总蛋白质的蛋白质，例如帕金森氏病和阿尔茨海默氏症的应用中的α-核蛋白 疾病。这些疾病基础的致病机制，目前没有 治疗，尚未完全理解。自噬，一种蜂窝回收途径，穿梭超过和 溶酶体降解的细胞成分受损。我们提出了构成 选择性自噬途径清除与ND相关的蛋白质聚集体。在哺乳动物细胞中， 在压力条件下，自噬已广泛研究，但几乎一无所知 关于人类细胞中的组成性选择性自噬过程或其调节。在这里，我们 提案，以扩展我们最近在酵母上有关两种构成选择性的研究 自噬途径及其对人类细胞的Rab1酵母同源物YPT1的调节。 在ND中隐含Rab1 GTPase，并提出了其激活以抑制积累 ND相关的聚合物。但是，rab1调节分泌和自噬，不是 清楚其激活会影响哪个过程。此外，Rab1秘密激活 它在肿瘤发生中暗示。为了阐明rab1的过程影响nd，它是 对于分泌和自噬的功能至关重要。在酵母中，我们成功了 使用两种方法在分泌和自噬中分离YPT1的功能：生成 自噬特异性YPT1突变和表征自噬特异性YPT1激活剂。 这些激活剂在两个组成型选择性自噬途径中刺激YPT1：清除 过量的膜蛋白和细胞质蛋白复合物的清除率。因为一切 玩家从酵母到人类细胞保存，我们建议确定我们的发现是否 与人类细胞有关。在AIM 1中，我们将尝试生成自噬特异性RAB1突变 在目标2-3中，我们将确定自噬选择激活剂是否刺激Rab1 两个不同的本构选择性自噬途径。 如果成功，这些工具将在以后的实验中使用，以确定自噬是否是否 特定的RAB1调制会影响ND相关蛋白质聚集体的清除。实现 该提案的目标和未来的实验将为您提供新颖的法规范式 ND相关蛋白质聚集体的清除率。此外，识别rab1调节剂特定的 对于本构选择性自噬，将提供新颖的ND治疗靶标，与 国家神经系统疾病和中风研究所的任务。