Investigating how nuclear pore components exploit an ER-dependent quality control pathway

研究核孔成分如何利用内质网依赖的质量控制途径

• 批准号: 10311782
• 负责人: Madison Lynn Pletan
• 金额: $ 3.75万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-08-01 至 2024-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10311782
• 关键词: Amyotrophic Lateral Sclerosis; Autophagocytosis; Cell Culture Techniques; Cell Nucleus; Cell physiology; Cells; Complex; Coupled; Cytoplasm; Cytosol; Data; Disease; Endoplasmic Reticulum; Event; Frontotemporal Dementia; Goals; Individual; Integral Membrane Protein; Kinesin; Lysosomes; Mammalian Cell; Mediating; Membrane; Modeling; Motor; Motor Neurons; Mus; Muscle Weakness; Muscular Atrophy; Neurodegenerative Disorders; Neurons; Nuclear; Nuclear Envelope; Nuclear Pore; Nuclear Pore Complex; Outcome Study; Paralysed; Pathogenesis; Pathogenicity; Pathologic; Pathway interactions; Phenotype; Pore Proteins; Process; Proteins; Quality Control; Reporting; Research; Role; Small Interfering RNA; Structure; System; Testing; Tissues; Transport Process; Work; age related neurodegeneration; base; frontotemporal lobar dementia-amyotrophic lateral sclerosis; human disease; kinectin; knock-down; loss of function; motor neuron degeneration; muscle strength; novel; nucleocytoplasmic transport; prevent; receptor; receptor binding; recruit; response; trafficking

Abstract Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease that primarily targets motor neurons, leading to progressive muscle weakness and paralysis. There is no cure for ALS or the related disorder frontotemporal dementia (FTD), largely because it is unclear which of the many implicated cellular pathways are causative. A growing number of studies have identified damage to the nuclear pore complex (NPC) as a key pathological phenotype in both ALS-diseased tissue and ALS models. This damage is characterized by defective nucleocytoplasmic transport and mislocalization of NPC components (“Nups”) to the cytosol. To examine the fate of mislocalized Nups, our research group has developed a model for NPC disruption whereby we deplete a key structural Nup and track the localization of other Nups. Strikingly, our preliminary data shows that the displaced Nups form aggregates in the endoplasmic reticulum, a process which is dependent on the ER transmembrane protein kinectin. These aggregates accumulate upon depletion of the major autophagy factor Beclin-1, suggesting that the Nups are targeted for ER-coupled autophagy. Together, these findings point to a novel nucleus-to-ER autophagy pathway that may be functioning when Nups are displaced in ALS. Based on this preliminary data, we hypothesize that the cellular motor protein kinesin-1 transports Nups from the nucleus to the ER (Aim 1A), and that this transport process also occurs in a disease-relevant cell culture model (Aim 1B). We further hypothesize that once at the ER, the Nup aggregates are cleared by receptor-mediated autophagy (Aim 2). This work will elucidate basic intracellular trafficking and quality control pathways. More importantly, understanding cellular response to mislocalized Nups may provide a better mechanistic picture of the progression of ALS/FTD.

抽象的 肌萎缩性外侧硬化症（ALS）是一种致命的神经退行性疾病，主要针对运动 神经元，导致渐进的肌肉无力和麻痹。无法治愈ALS或 相关疾病额颞痴呆（FTD），主要是因为尚不清楚许多 实施的细胞途径是建造的。越来越多的研究确定了对 核孔复合物（NPC）是ALS抑制组织和 ALS模型。这种损害的特征是有缺陷的核细胞质运输和 NPC组件（“ NUPS”）对细胞质的错误定位。 为了检查错误定位的NUP的命运，我们的研究小组开发了一个NPC的模型 破坏了我们破坏关键的结构性NUP并跟踪其他NUP的本地化。 令人惊讶的是，我们的初步数据表明，流离失所的NUP在内质中形成聚集体 网状，这是取决于ER跨膜蛋白动力素的过程。这些 主要自噬要素beclin-1耗尽后，聚集体积累，表明 NUP针对ER耦合自噬。这些发现一起指出了一个新的核对核 当NUP在ALS中移位时，自噬途径可能起作用。基于此 初步数据，我们假设细胞运动蛋白驱动蛋白-1从 ER的细胞核（AIM 1A），并且这种运输过程也发生在与疾病相关的细胞中 文化模型（目标1b）。我们进一步假设，一旦在ER处清除了NUP骨料 通过接收器介导的自噬（AIM 2）。这项工作将阐明基本的细胞内贩运和 质量控制途径。更重要的是，了解细胞对错误定位的NUP的反应 可以提供ALS/FTD进展的更好的机械图。