Mechanisms of Mutant Prion Protein Aggregation Within Endolysosomal Pathways

内溶酶体途径中突变型朊病毒蛋白聚集的机制

• 批准号: 10618881
• 负责人: SANDRA E Encalada
• 金额: $ 90.82万
• 依托单位: SCRIPPS RESEARCH INSTITUTE, THE
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-05-15 至 2027-04-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10618881
• 关键词: Alzheimer' s Disease; Alzheimer' s disease related dementia; Amyloid beta-Protein; Architecture; Automobile Driving; Autopsy; Axon; Binding; Biological; Brain; Brain Pathology; Brain region; Cells; Characteristics; Complex; Cytoskeleton; Deacetylation; Deposition; Development; Diagnosis; Down-Regulation; Electron Microscopy; Electrons; Elements; Endocytic Vesicle; Endosomes; Excision; Functional disorder; Generations; Genetic; Goals; Golgi Apparatus; Health; Human; Impaired Cytoskeletal Integrity; Impairment; Investigation; Mediating; Membrane; Microtubules; Mission; Mitochondria; Modeling; Molecular; Molecular Conformation; Multivesicular Body; Mus; Mutation; Nerve Degeneration; Neurites; Neurodegenerative Disorders; Neurologic; Neurons; Organelles; Pathogenesis; Pathology; Pathway interactions; Patients; Pharmacological Treatment; Poison; PrP; Prion Diseases; Prions; Proteins; Proteomics; Public Health; Research; Rodent; Role; Route; Site; Sorting; Structure; Testing; United States National Institutes of Health; Vacuole; Vesicle; aggregation pathway; cofactor; design; in vivo; innovation; insight; light microscopy; mouse model; mutant; neurofilament; neurotoxic; novel; pharmacologic; protein aggregation; targeted treatment; tau Proteins; therapy development; trafficking; treatment strategy

Ultrastructural studies of human patient brains with prion disease have revealed the accumulation of misfolded PrP within dystrophic neurites inside endolysosomes. Other complex structures co- exist within these dystrophies and are now considered common features of prion pathologies, including autophagic vacuole-like membrane-bound organelles, lysosomal electron-dense bodies, and enlarged endolysosomes. The mechanisms leading to the formation of these structures remain unknown. Our studies have identified an endolysosomal pathway in mammalian neurons that we call axonal rapid endosomal sorting and transport-dependent aggregation (ARESTA), that drives the formation of neurotoxic axonal aggregates of a misfolded mutant prion protein (PrP) inside endo-membrane structures that we call “endoggresomes”. The long-term goal of this proposal is to characterize the endocytic pathways that play a role in the pathophysiology of prion diseases, Alzheimer’s disease, and of Alzheimer’s disease related dementias, that will provide actionable targets for their pharmacological treatment. The objectives of this proposal are (i) to determine the generality of the ARESTA pathway in formation of endoggresomes in axons of neurons expressing various familial PrP mutations, and to characterize the molecular and ultrastructural architecture of neurotoxic endoggresomes; (ii) to determine the mechanisms of mutant PrP endoggresome-mediated axonal impairments; and (iii) to determine how the endolysosomal ARESTA pathway modulates the formation of axonal mutant PrP aggregates in vivo. The central hypotheses are (i) ARESTA drives the formation of endoggresomes in various familial prion diseases by interactions with co-factors within endocytic routes; (ii) mutant PrP endoggresome-induced pathologies act as axonotoxicity hubs that inhibit neuronal function by impairing local axonal cytoskeletal-organelle interactions, and (iii) endolysosomal pathways modulate the formation and pathology of mutant PrP aggregates in vivo. The proposed research is innovative because it provides a conceptual framework for developing models that include novel endolysosomal pathway-mediated mechanisms to explain how intra-axonal aggregates form and impair neuronal function in the prionopathies. The proposed research is significant because it identifies the endocytic pathway and specifically ARESTA and endoggresomes, as anti- aggregation targets for therapies to inhibit aggregate formation and reverse related pathologies. As amyloid-b peptides, tau, and most proteins that misfold in neurodegeneration transit within endocytic routes at some point in their processing routes, our findings are expected to be relevant to Alzheimer’s disease and Alzheimer’s disease related dementias.

对人类朊病毒病患者大脑的超微结构研究揭示了 内溶酶体内营养不良的神经突内错误折叠的 PrP。其他复杂结构共同 存在于这些营养不良中，现在被认为是朊病毒病理学的共同特征， 包括自噬液泡样膜结合细胞器、溶酶体电子致密 体和扩大的内溶酶体。导致这些现象形成的机制 结构仍然未知。我们的研究已经确定了哺乳动物的内溶酶体途径 我们称之为轴突快速内体分选和运输依赖性聚集的神经元 （ARESTA），驱动错误折叠突变朊病毒的神经毒性轴突聚集体的形成 内膜结构内的蛋白质（PrP），我们称之为“内格雷体”。长期目标 该提案的目的是描述在病理生理学中发挥作用的内吞途径 朊病毒病、阿尔茨海默病以及阿尔茨海默病相关的痴呆症， 为其药物治疗提供可行的目标。该提案的目标是 (i) 确定 ARESTA 途径在轴突内客体形成中的普遍性 表达各种家族性 PrP 突变的神经元，并表征分子和 神经毒性内溶酶体的超微结构； (ii) 确定机制 突变型 PrP 内吞酶体介导的轴突损伤； (iii) 确定如何 内溶酶体 ARESTA 通路调节轴突突变型 PrP 聚集体的形成 体内。中心假设是（i）ARESTA 驱动各种内溶酶体的形成 通过与内吞途径中的辅因子相互作用而导致的家族性朊病毒病； (ii) 突变型 PrP 内溶体诱导的病理学作为轴突毒性中枢，通过以下方式抑制神经元功能： 损害局部轴突细胞骨架-细胞器相互作用，以及（iii）内溶酶体途径 调节体内突变型 PrP 聚集体的形成和病理学。拟议的研究 之所以具有创新性，是因为它为开发模型提供了一个概念框架，其中包括新颖的 内溶酶体途径介导的机制来解释轴突内聚集体如何形成和 损害朊病毒病中的神经元功能。拟议的研究意义重大，因为它 确定了内吞途径，特别是 ARESTA 和内吞体，作为抗 抑制聚集体形成和逆转相关病理的疗法的聚集靶标。 作为淀粉样蛋白 B 肽、tau 蛋白和大多数在神经退行性变过程中错误折叠的蛋白质， 内吞途径在其加工路线中的某个点，我们的研究结果预计是相关的 阿尔茨海默病和阿尔茨海默病相关的痴呆症。