Nuclear transport as a molecular and cellular vulnerability in AD

核运输是 AD 中分子和细胞的脆弱性

• 批准号: 10213341
• 负责人: Timothy J Mitchison
• 金额: $ 48.06万
• 依托单位: HARVARD MEDICAL SCHOOL
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-07-15 至 2023-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10213341
• 关键词: Address; Age; Aging; Alzheimer' s Disease; Alzheimer' s disease related dementia; Binding; Biological Assay; Biological Models; Brain; Cell Nucleus; Cell fusion; Cell model; Cells; Cellular biology; Cytoplasm; Defect; Diffusion; Drug Targeting; Elements; Evaluation; Exportins; Exposure to; Family; Future; Gel; Gene Expression; Generations; Genetic; Glycine; Goals; Health; Heart; Human; Hydrogen Bonding; Hydrophobic Interactions; Hydrophobicity; Image Analysis; Immunoassay; Impairment; Importins; Interphase Cell; Karyopherins; Kinetics; Light; Link; Measurement; Measures; Microscopy; Modeling; Modification; Molecular; Movement; Mus; Nerve Degeneration; Neurobiology; Neurodegenerative Disorders; Neuronal Differentiation; Neurons; Nuclear; Nuclear Envelope; Nuclear Export; Nuclear Import; Nuclear Pore; Nuclear Pore Complex; Nuclear Proteins; Optical reporter; Pathology; Pathway interactions; Patients; Peptides; Pharmaceutical Preparations; Pharmacology; Phenylalanine; Pore Proteins; Protein Glycosylation; Proteins; Proteomics; Proxy; Publications; Regulation; Research; Resolution; Signal Transduction; Techniques; Testing; aging brain; alpha Karyopherins; base; cell type; drug candidate; drug development; drug discovery; drug testing; experimental study; exportin 1 protein; glycosylation; heterokaryon; hydrophilicity; in vivo; induced pluripotent stem cell; knock-down; microscopic imaging; misfolded protein; mouse model; nerve stem cell; novel; nucleocytoplasmic transport; optogenetics; prevent; programs; relating to nervous system; success; tau Proteins; tau mutation; therapeutic candidate; tool; trafficking

Abstract Molecular trafficking between the nucleus and the cytoplasm is essential for cellular health and is tightly regulated in all cell types including those in the brain. Recent publications demonstrated nuclear transport defects in neurons in Alzheimer’s disease (AD) and related dementias (ADRDs). AD/ADRDs are caused, in part, by misfolded tau protein, suggesting misfolded tau may impair nuclear transport by aberrantly interacting with nuclear pore proteins. We propose that late-onset neurodegenerative disease, such as AD, reflects two vulnerabilities: (i) At the cellular level, intrinsic loss of nuclear import efficiency during the neural differentiation program sensitizes the neurons to damages associated with misfolded tau. (ii) At the molecular level, nuclear pore complexes (NPCs) are selectively vulnerable to disruption by misfolded proteins because their activity depends on exposed hydrophobic phenylalanine-glycine (FG) repeats that are easily disrupted by misfolded AD/ADRD-tau and turn over very slowly. To test these hypothesis, we developed novel optogenetic nuclear transport assays, based on photo-activatable NLS/NES elements. We now propose to combine Mitchison group’s expertise in advanced microscopy and image analysis with Song group’s expertise in neuron cell biology and pathology models to measure rates of nuclear import and export in living neurons and test the effects of neural differentiation, misfolded tau, and drug candidates that may alleviate the effects of misfolded tau on nuclear transport. We will (i) characterize the change in nuclear transport rates during neural differentiation, (ii) compare the sensitivity of nuclear transport to AD/ADRD-related misfolded tau challenges (e.g. G272V-tau and P301S-tau) in neurons and neural progenitors, and (iii) investigate the underlying molecular mechanisms using super-resolution microscopy and immunoassays. The transport assays will also enable future translational programs aimed at rescuing nuclear transport in aging neurons. As a test case, we will characterize drugs that increase O-linked b-N-acetylglucosamine (O-GlcNAc) modification of intracellular proteins. This modification is thought to inhibit aggregation of misfolded proteins such as tau. However, FG repeat in NPC are among the most O-GlcNAc modified proteins. We propose that the function of this druggable modification is to protect the intrinsic vulnerability of NPCs to damage by misfolded proteins. Success on this R21 pilot will set the stage for moving our optical reporter strategy into mouse models of brain aging and degeneration, and for identifying drug targets and testing candidate therapeutic molecules in high- content assay formats.

抽象的 细胞核和细胞质之间的分子运输对于细胞健康至关重要，并且紧密 在包括大脑中的所有细胞类型中调节。最近的出版物表明核运输 阿尔茨海默氏病（AD）和相关痴呆症（ADRDS）的神经元缺陷。广告/adrd是引起的 部分，通过错误折叠的tau蛋白，表明错误折叠的tau可能会因异常相互作用而损害核运输 与核孔蛋白。我们提出，晚发神经退行性疾病（例如AD）反映了两种 漏洞：（i）在细胞水平上，神经分化过程中核进口效率的内在丧失 程序将神经元视为与错误折叠的tau相关的损害。 （ii）在分子水平上，核 孔复合物（NPC）有选择地容易受到错误折叠蛋白的破坏，因为它们的活性 取决于暴露的疏水苯丙氨酸 - 甘氨酸（FG）重复，这些重复易于折叠。 广告/adrd-tau，非常缓慢地翻转。为了检验这些假设，我们开发了新型的光遗传核 运输分析，基于可传递的NLS/NES元素。我们现在建议将米奇森结合起来 Group在高级显微镜和图像分析方面的专业知识以及Song Group在神经元细胞方面的专业知识 生物学和病理模型，以衡量活神经元中核进出口速率并测试 神经元分化，错误折叠的TAU和候选药物的影响可能会减轻错误折叠的影响 Tau在核运输中。我们将（i）表征中性核运输速率的变化 分化，（ii）将核运输的敏感性与与AD/ADRD相关的错误折叠的TAU挑战进行比较 （例如，神经元和神经元祖细胞中的G272V-TAU和P301S-TAU，（iii）研究基础 使用超分辨率显微镜和免疫测定的分子机制。运输分析也将 使未来的翻译计划旨在营救衰老神经元中的核运输。作为测试案例，我们 将表征增加O连锁的B-N-乙酰葡萄糖（O-GLCNAC）修饰的药物 蛋白质。这种修饰被认为抑制了错误折叠蛋白（例如tau）的聚集。但是，FG NPC中的重复是最大的O-GLCNAC修饰蛋白之一。我们提出了这个功能 可药物的修改是为了保护NPC因错误折叠蛋白损害的固有脆弱性。 此R21飞行员的成功将为将我们的光学记者策略转移到大脑的模型中奠定了基础 衰老和变性，并用于鉴定药物靶标的和测试候选治疗分子 内容测定格式。

项目成果

Editorial: Cytoskeletal alterations in aging and disease.

• DOI: 10.3389/fcell.2023.1359465
• 发表时间: 2023
• 期刊: FRONTIERS IN CELL AND DEVELOPMENTAL BIOLOGY
• 影响因子: 5.5
• 作者: Brill, Monika S.;Fassier, Coralie;Song, Yuyu
• 通讯作者: Song, Yuyu