Nuclear import receptors as modifiers of TDP-43 phase transition and toxicity in FTD/ALS

核输入受体作为 TDP-43 相变和 FTD/ALS 毒性的调节剂

• 批准号: 10608681
• 负责人: Wilfried Rossoll
• 金额: $ 73.05万
• 依托单位: MAYO CLINIC JACKSONVILLE
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-12-01 至 2027-11-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10608681
• 关键词: Address; Alzheimer' s Disease; Alzheimer' s disease related dementia; Amyotrophic Lateral Sclerosis; Animal Model; Autopsy; Biochemical; Biological Assay; Brain; Cell Culture Techniques; Cell Nucleus; Cell model; Cell physiology; Complement; Complex; Cytoplasm; Data; Defect; Disease; Drosophila genus; Engineering; Feedback; Frontotemporal Dementia; Functional disorder; Future; Gene Transfer Techniques; Goals; Human; Importins; In Vitro; Karyopherins; Knowledge; Liquid substance; Methods; Modeling; Molecular; Molecular Chaperones; Nature; Nerve Degeneration; Neurodegenerative Disorders; Neurons; Nuclear; Nuclear Import; Nuclear Pore Complex Proteins; Orthologous Gene; Outcome; Pathogenesis; Pathologic; Pathology; Patients; Phase; Phase Transition; Phenotype; Physiological; Process; Protein Engineering; Proteins; RNA Splicing; RNA-Binding Proteins; Recombinant Proteins; Reporting; Ribonucleoproteins; Role; Secondary to; Slice; Solubility; TDP-43 aggregation; Testing; Therapeutic; Therapeutic Intervention; Tissues; Toxic effect; Variant; brain tissue; design; disease phenotype; effective therapy; experimental study; fly; frontotemporal lobar dementia amyotrophic lateral sclerosis; gain of function; human disease; in vivo; in vivo Model; loss of function; mouse model; mutant; neuropathology; novel; novel therapeutic intervention; nucleocytoplasmic transport; prevent; prion-like; protein TDP-43; protein aggregation; proteotoxicity; receptor; receptor function; recruit; structural biology; targeted treatment; therapeutic target; therapy development

The goal of this project is to gain a detailed mechanistic understanding of how nuclear-import receptors (NIRs) can prevent and reverse the cytoplasmic mislocalization and accumulation of insoluble protein aggregates of the RNA-binding protein TDP-43 in the pathogenesis of common neurodegenerative disorders. TDP-43 pathology is a hallmark of frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS), but is also commonly found in Alzheimer’s disease (AD) and other AD-related dementias (ADRDs), marking it as a high priority target for therapy development. Our labs have discovered that 1) TDP-43 pathology is characterized by the co-aggregation of TDP-43 with FG nucleoporins (FG-Nups) in the cytoplasm, causing nucleocytoplasmic transport defects and 2) NIRs can reduce the aberrant phase transition of TDP-43 and other disease-causing RNA-binding proteins with prion-like domains. Our data demonstrate that specific NIRs can reverse the hallmarks of TDP-43 proteinopathy in cellular and animal models of FTD and ALS. Based on our findings, we propose a novel non-canonical role for NIRs as potent molecular chaperones that are recruited by FG-Nups into pathological TDP-43 aggregates, where they act to to reverse the aberrant phase transition and restore the normal nuclear localization and splicing functions of TDP-43, suggesting a promising new strategy for therapeutic intervention. To test this hypothesis, our team of experts in cellular and animal models of FTD (an ADRD) and ALS, as well as structural biology approaches, will use cutting edge in vitro and in vivo methods to gain a detailed mechanistic understanding of how NIRs restore solubility, nuclear localization and normal function of TDP-43; how NIRs reduce neurodegeneration; how NIR dysfunction contributes to human disease; and how we can use this knowledge of NIR functions to develop future therapeutic strategies for TDP-43 proteinopathies. Our specific aims are: (i) to determine how NIRs restore proper TDP-43 localization and reduce aberrant phase transition in vitro, using a combination of advanced neuronal cell culture models of FTD and ALS and biochemical characterization of TDP-43 liquid-liquid phase separation (LLPS) and fibrillization, and rational protein engineering approaches to potentiate the chaperone activity of NIRs; and (ii) to identify how NIRs reduce TDP-43-dependent neurodegeneration in cellular and animal models in vivo, employing Drosophila, organotypic slice cultures and somatic brain transgenesis in TDP-43 proteinopathy mouse models, and clarifying the nature of NIR pathology in ALS and FTD (an ADRD) patient brain tissue. Successful outcome of this project will clarify the role of NIRs in regulating TDP-43 phase transition during pathogenesis and how this activity can restore normal localization and cellular function of TDP-43. This knowledge will be critical for developing new therapeutic strategies to target aberrant phase separation in ALS, FTD, and other devastating AD-related neurodegenerative disorders with TDP-43 proteinopathy.

该项目的目标是详细了解核输入受体 (NIR) 如何预防和逆转常见神经退行性疾病发病机制中 RNA 结合蛋白 TDP-43 的细胞质错误定位和不溶性蛋白聚集体的积累TDP-43 病理学是额颞叶痴呆 (FTD) 和肌萎缩侧索硬化症 (ALS) 的标志，但也常见于阿尔茨海默病 (AD) 和其他 AD 相关痴呆 (ADRD)，使其成为治疗开发的高度优先目标，我们的实验室发现 1) TDP-43 病理学的特点是 TDP-43 与 FG 核孔蛋白 (FG-Nups) 的共聚集。 2) NIR 可以减少 TDP-43 和其他致病 RNA 结合蛋白的异常相变我们的数据表明，特定的 NIR 可以逆转 FTD 和 ALS 的细胞和动物模型中 TDP-43 蛋白病的特征，根据我们的研究结果，我们提出 NIR 作为有效分子伴侣的一种新的非典型作用。被 FG-Nups 招募到病理性 TDP-43 聚集体中，在那里它们起到逆转异常相变并恢复 TDP-43 正常核定位和剪接功能的作用，这表明为了验证这一假设，我们的 FTD（ADRD）和 ALS 细胞和动物模型以及结构生物学方法专家团队将使用尖端的体外和体内方法来获得这一结果。详细了解 NIR 如何恢复 TDP-43 的溶解度、核定位和正常功能；以及 NIR 功能障碍如何导致人类疾病；我们的具体目标是：（i）结合先进的 FTD 和 ALS 神经元细胞培养模型以及 TDP-43 的生化表征，确定 NIR 如何在体外恢复正确的 TDP-43 定位并减少异常相变。 43 液-液相分离 (LLPS) 和纤维化，以及合理的蛋白质工程方法，以增强 NIR 的伴侣活性；以及 (ii) 确定 NIR 如何减少体内细胞和动物模型中 TDP-43 依赖性神经变性，在 TDP-43 蛋白病小鼠模型中采用果蝇、器官型切片培养物和体细胞脑转基因，并阐明 ALS 和 FTD（ADRD）患者脑组织中 NIR 病理学的性质该项目的成功结果将阐明 NIR 在发病机制中调节 TDP-43 相变的作用，以及这种活性如何恢复 TDP-43 的正常定位和细胞功能。这些知识对于开发针对 ALS、FTD 和其他具有 TDP-43 蛋白病的破坏性 AD 相关神经退行性疾病的异常相分离的新治疗策略至关重要。