Evaluation of a novel NLK function in lysosome biogenesis and neurodegenerative diseases

1R01AG074609-01 林章和 在大多数神经退行性疾病中，包括阿尔茨海默病（AD），一种或多种蛋白质在疾病进展过程中聚集。在肌萎缩侧索硬化症（ALS）和额颞叶痴呆（FTD）、AD和其他AD相关痴呆（ADRD）的情况下，在大部分散发性和家族性疾病患者中观察到反式反应DNA结合蛋白43 kDa（TDP-43）的细胞质内含物。细胞质TDP-43的这种异常积累被认为是毒性功能获得和加剧核功能丧失致病机制的基础;因此，预防这些内含物的形成或促进其清除可能是TDP-43蛋白病（如AD和ADRD）的有效治疗方法。目前，没有有效改变与TDP-43蛋白质病相关的大多数神经退行性疾病的病程的治疗剂。我们最近发现Nemo样激酶（Nlk）作为溶酶体的负调节因子，溶酶体是参与细胞蛋白质质量控制的关键细胞器，能够清除有毒的聚集蛋白。本提案旨在更好地理解Nlk调节神经系统中溶酶体基因表达的基本分子机制，并测试Nlk在TDP-43聚集的ADRD动物模型中的调节作用。我们提出以下三个具体目标。目的1将采用无偏见和有针对性的方法来揭示神经元中Nlk对溶酶体基因表达的调控的基本机制。目的2将使用野生型和TDP-43动物模型来确定哪些细胞类型在体内神经系统中介导Nlk在溶酶体和TDP-43蛋白质病的调节中的功能。目的3将扩大所提出的研究的范围，以了解在TDP-43聚集的动物模型中Nlk减少的治疗意义，通过在体内成年期不同时间的Nlk水平的遗传和药理学降低。在此过程中，我们将测试Nlk减少对控制ADP-43小鼠ADRD模型中病理和运动行为变化的发生和进展的影响。目的2和3将提供关于溶酶体调节在蛋白质聚集障碍临床前模型中的有效性的关键原理证明证据。总之，该项目将揭示参与神经元中溶酶体调节的新型分子，这些分子可能是治疗各种神经退行性疾病（包括AD和几种AD相关疾病）的潜在靶点。

1R01AG074609-01 Janghoo Lim In the majority of neurodegenerative diseases, including Alzheimer’s disease (AD), one or more proteins aggregate over the course of disease progression. In the case of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD), AD, and other AD-related dementias (ADRDs), cytoplasmic inclusions of transactive response DNA binding protein 43 kDa (TDP-43) are observed in a large percentage of patients with sporadic and familial forms of disease. This aberrant accumulation of cytoplasmic TDP-43 is thought to underlie gain of toxic functions and exacerbate loss of nuclear function pathogenic mechanisms; therefore, preventing the formation or promoting the clearance of these inclusions may be an effective therapeutic approach for TDP-43 proteinopathies, such as AD and ADRDs. Currently, there are no therapeutics that effectively alter the course of most neurodegenerative diseases associated with TDP-43 proteinopathy. We have recently identified Nemo-like kinase (Nlk) as a negative regulator of the lysosome, a key organelle involved in cellular protein quality control that is capable of clearing toxic aggregated proteins. This proposal aims to better understand the basic molecular mechanism of Nlk’s regulation of lysosome gene expression in the nervous system and to test the modulatory effects of Nlk in ADRD animal models of TDP-43 aggregation. We propose the following three specific aims. Aim 1 will employ unbiased and targeted approaches to uncover fundamental mechanistic insights into the regulation of lysosome gene expression by Nlk in neurons. Aim 2 will determine which cell types mediate the function of Nlk in the regulation of the lysosome and TDP-43 proteinopathy in the nervous system in vivo using wild-type and TDP-43 animal models. Aim 3 will expand the scope of the proposed study to understand the therapeutic implications of Nlk reduction in animal models of TDP-43 aggregation through genetic and pharmacological reduction of Nlk levels at varying times in adulthood in vivo. In doing so, we will test the effect of Nlk reduction in the control of the onset and progression of pathological and motor behavioral changes in TDP-43 mouse models of ADRD. Aims 2 and 3 will provide critical proof-of-principle evidence regarding the effectiveness of lysosomal modulation in pre-clinical models of protein aggregation disorders. Together, this project will reveal novel molecules involved in lysosomal regulation in neurons that may be potential targets in the treatment of various neurodegenerative diseases, including AD and several AD-related disorders.