Mechanisms of Endosomal Dysfunction at Synapses in A-Synuclein Pathology

A-突触核蛋白病理学中突触内体功能障碍的机制

• 批准号: 10740158
• 负责人: Cristina Roman-Vendrell
• 金额: $ 12.43万
• 依托单位: MARINE BIOLOGICAL LABORATORY
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-07-01 至 2025-06-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10740158
• 关键词: Acute; Address; Advanced Development; Affect; Appearance; Back; Brain; Cell membrane; Cells; Clathrin; Cognitive deficits; Data; Defect; Dementia with Lewy Bodies; Diameter; Disease; Dyes; Early Endosome; Electrons; Electrophysiology (science); Endocytosis; Endosomes; Equilibrium; Event; Functional disorder; Human; Human body; Image; Immunofluorescence Immunologic; Impairment; Individual; Knowledge; Laboratory Research; Lampreys; Link; Measures; Mediating; Membrane; Methods; Microscopic; Modeling; Molecular; Molecular Analysis; Molecular Weight; Nerve Degeneration; Neurodegenerative Disorders; Neurons; Parkinson Disease; Parkinson' s Dementia; Pathogenesis; Pathology; Phenotype; Physiological; Physiology; Positioning Attribute; Postdoctoral Fellow; Process; Proteins; Recombinants; Recycling; Research; Research Personnel; Structure; Synapses; Synaptic Vesicles; Techniques; Testing; Vesicle; Work; Yeasts; alpha synuclein; cellular targeting; coated pit; dimer; human disease; human subject; improved; innovation; insight; late endosome; monomer; neuropathology; neurotoxicity; neurotransmission; novel; presynaptic; synaptic function; synuclein; synucleinopathy; therapy development; trafficking; uptake

ABSTRACT/SUMMARY Synucleinopathies, including Parkinson’s disease (PD) and Dementia with Lewy Bodies (DLB), are neurodegenerative diseases characterized by the abnormal aggregation of α-synuclein. Furthermore, it is well known that α-synuclein exists in multiple structural forms (i.e., monomers and oligomers) that contribute to neurotoxicity by distinct mechanisms. While there is substantial evidence that accumulation of α-synuclein broadly impairs synaptic vesicle endocytosis, the effects of distinct α-synuclein species on synaptic endosomal trafficking are largely unknown. The proposed studies will be the first to investigate in detail how accumulation of different oligomeric α-synuclein species affect endosomal trafficking at vertebrate synapses and the underlying cellular and molecular mechanisms. Using the lamprey synapse model, a classical vertebrate model, we can deliver precise amounts of purified -synuclein species directly into synapses. This allows us to independently test the effects of different -synuclein species on presynaptic ultrastructure and function. Our preliminary studies suggest that excess monomeric -synuclein impairs endosomal trafficking, as shown by a reduction in the number of synaptic vesicles and concomitant increase in the number of atypical large vesicles, reminiscent of endosomes. This provides an excellent model for the proposed studies. In Aim 1 (K99), we will determine how monomeric human -synuclein affects endosomal trafficking at synapses. In Aim 2 (R00), we will determine how oligomeric human -synuclein contribute to -synuclein-mediated endosomal dysfunction at synapses. The focus will be on different oligomeric -synuclein species including dimers, small oligomers and larger oligomers from PD/DLB human brains. These studies will provide critical understanding for the development of therapies for improving synaptic function in synucleinopathies.

摘要/摘要 突触核疾病，包括帕金森氏病（PD）和Lewy身体（DLB）的痴呆症 神经退行性疾病的特征是α-突触核蛋白的异常聚集。此外，很好 知道α-突触核蛋白以多种结构形式（即单体和低聚物）存在，有助于 神经毒性通过不同的机制。虽然有大量证据表明α-核蛋白的积累 广泛损害合成囊泡内吞作用，这是不同α-突触核蛋白物种对合成内体的影响 贩运在很大程度上是未知的。拟议的研究将是第一个详细研究如何积累的研究 不同的寡聚α-突触核蛋白物种会影响脊椎动物突触的内体运输和 潜在的细胞和分子机制。使用lamprey突触模型，经典的脊椎动物 模型，我们可以将精确量的纯含突触核蛋白直接输送到突触中。这使我们能够 独立地测试不同突触核蛋白物种对突触前超微结构和功能的影响。我们的 初步研究表明，超过单体s-核蛋白会损害内体贩运，如A所示 突触蔬菜的数量减少，同时增加非典型大蔬菜的数量， 让人联想到内体。这为拟议的研究提供了出色的模型。在AIM 1（K99）中，我们将 确定单体人类突触核蛋白如何影响突触的内体运输。在AIM 2（R00）中，我们 将确定低聚人类突触核蛋白在 突触。重点将放在不同的寡聚核素种类上，包括二聚体，小寡聚物和 PD/DLB人类大脑的较大低聚物。这些研究将为 开发用于改善突触核苷的突触功能的疗法。