TDP-43 acetylation as a pathogenic modification in ALS & related proteinopathies

描述(申请人提供)：肌萎缩侧索硬化症(ALS)是一种毁灭性的运动神经元病，存活率为3-5年，没有治疗方法。43kD的TAR DNA结合蛋白(TDP-43)是一种核RNA和DNA结合蛋白，在大多数ALS患者和痴呆患者的大脑和脊髓中异常聚集，将ALS和FTLD-TDP置于TDP-43蛋白病的疾病谱中。虽然TDP-43的病理与疾病的发生和发展有关，但关于TDP-43如何聚集导致进行性神经变性知之甚少。我的长期目标是揭示促进TDP-43聚集的致病机制，这将为未来针对这些衰弱疾病的治疗提供见解。翻译后修饰与神经退行性疾病的进展有关。利用我在乙酰化生物学方面的背景，我以前证明了tau蛋白的乙酰化促进了阿尔茨海默病和相关的tauopathies(NAT Commun)中的缠结形成。2011~2：252)。我现在已经证明了TDP-43是乙酰化的，从而突出了一种新的TDP-43修饰，它可能与ALS和相关的蛋白质病有关。这一建议的中心假设是确定TDP-43的乙酰化是否促进聚集和神经变性。为了实现这一目标，我将从指导实验室获得神经病理学方面的专业知识，并分析ALS和FTLD-TDP死后脑和脊髓以及以TDP-43病理和神经退化为特征的TDP-43转基因小鼠的TDP-43乙酰化。为了直接确定乙酰化TDP-43是否促进疾病，将对原代神经元培养和表达乙酰化TDP-43的转基因小鼠进行病理特征、毒性和神经变性的评估，这些病理特征、毒性和神经变性概括了人类TDP-43蛋白病变。在确定了TDP-43乙酰化与疾病的相关性后，独立阶段将利用体外和基于细胞的方法来研究乙酰化在导致TDP-43与靶基因和RNA结合受损导致TDP-43功能丧失的生物学意义。最后，作为一名独立的研究员，我将利用神经退行性疾病的K99阶段训练来生成高乙酰化TDP-43的小鼠模型，并确定大脑和骨骼肌中的ALS表型。这些创新的研究将强调TDP-43乙酰化是与ALS和相关的TDP-43蛋白病变的进展有关的关键修饰。

DESCRIPTION (provided by applicant): Amyotrophic Lateral Sclerosis (ALS) is a devastating motor neuron disease with a 3-5 year survival rate and no disease-modifying therapies. TAR DNA-binding protein of 43kD (TDP-43) is a nuclear RNA and DNA binding protein that becomes abnormally aggregated in the brain and spinal cord of most ALS patients as well as a subset of dementia patients (frontotemporal lobar degeneration with TDP-43 pathology, or FTLD-TDP), placing ALS and FTLD-TDP within a spectrum of diseases known as TDP-43 proteinopathies. Although TDP-43 pathology has been implicated in disease onset and progression, little is known about how TDP-43 becomes aggregated leading to progressive neurodegeneration. My long-term goal is to uncover the pathogenic mechanisms that promote TDP-43 aggregation, which will provide insights for future therapies against these debilitating diseases. Post-translational modifications have been implicated in the progression of neurodegenerative diseases. Using my background in acetylation biology, I previously demonstrated that acetylation of the tau protein promotes tangle formation in Alzheimer's disease and related tauopathies (Nat Commun. 2011~2:252). I have now demonstrated that TDP-43 is subject to acetylation, thus highlighting a new TDP-43 modification that is potentially linked to ALS and related proteinopathies. The centra hypothesis of this proposal is to determine whether acetylation of TDP-43 promotes aggregation and neurodegeneration. To accomplish this goal, I will acquire expertise in neuropathology from the mentoring laboratory and analyze TDP-43 acetylation in ALS and FTLD-TDP post-mortem brain and spinal cord as well as TDP-43 transgenic mice characterized by TDP-43 pathology and neurodegeneration. To directly determine whether acetylated TDP-43 promotes disease, primary neuronal cultures and transgenic mice expressing acetylated TDP-43 will be evaluated for pathological hallmarks, toxicity, and neurodegeneration that recapitulate human TDP-43 proteinopathies. Having established the disease relevance of TDP-43 acetylation, the independent phase will utilize in vitro and cell-based approaches to investigate the biological significance of acetylation in causing impaired TDP- 43 binding to target genes and RNAs, leading to a TDP-43 loss of function. Finally, as an independent investigator, I will utilize K99 phase training in neurodegenerative disease to generate a mouse model of hyper-acetylated TDP-43 and determine the ALS phenotype in both brain and skeletal muscle. These innovative studies will highlight TDP-43 acetylation as a critical modification linked to the progression of ALS and related TDP-43 proteinopathies.