Disruption of Nucleocytoplasmic Transport in FUS-related Neurodegenerative Diseases

最近出现了蛋白质和核糖核酸通过核孔的核质转运受损 作为神经退行性变的中心机制。事实上，我们最近已经表明，突变的亨廷顿蛋白明显 加剧与衰老相关的核完整性改变和NCT的破坏，以及核孔介导的缺陷 与C9ORF72相关的肌萎缩侧索硬化症(ALS)和额颞叶痴呆中也发现了转运 (FTD)。在这里，我们证明了突变的FUS的表达，一种与ALS和FTD相关的蛋白质，会导致核的丢失 孔洞完整性、核膜形态改变和其他与多发性、相关性NCT中断相关的表型 模型包括同基因的人类神经元和一种新的FUS敲入小鼠模型。在这个项目中，我们将进一步 在ALS和FTD中询问疾病相关FUS和受损NCT之间的关系 上述模型系统和人中枢神经系统组织(目标1)。为了阐明基因表达的机制， 突变的fus诱导NCT相关表型，我们将进一步探讨fus与核孔的相互作用。 蛋白质，并检验涉及突变的fus和核孔蛋白的异常相变的假设 促成中断的国家工作队(目标2)。我们还假设，受损的NCT通过错误定位导致毒性 转录本和蛋白质，这一概念将通过RNA测序和蛋白质组学进行测试，以比较基因表达 突变型FUS与对照神经元细胞分离后，NCT相关表现的前后 表型(目标3)。最后，我们将测试靶向核输出在FUS人类神经元中的治疗潜力 使用已被证明对多种人类疾病既安全又有效的策略的小鼠(目标4)。 两个学术团体和一个工业合作伙伴之间的协同合作(谁将提供治疗 用于我们实验室研究的化合物)有可能发现对疾病的新的机械性见解，并建立 靶向核浆转运在ALS/FTD中的治疗潜力。

Impaired nucleocytoplasmic transport (NCT) of protein and RNA through the nuclear pore has recently emerged as a central mechanism in neurodegeneration. Indeed, we have recently shown that mutant huntingtin markedly exacerbates aging-related alterations in nuclear integrity and disruption of NCT, and defects in nuclear pore-mediated transport have also been uncovered in C9ORF72-related amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Here, we demonstrate that expression of mutant FUS, a protein linked to ALS and FTD, leads to a loss of nuclear pore integrity, altered nuclear envelope morphology and other phenotypes related to disrupted NCT in multiple, relevant models including isogenic human neurons and a novel FUS knock-in mouse model. In this project, we will further interrogate the relationship between disease-associated FUS and impaired NCT in ALS and FTD using the aforementioned model systems and human CNS tissues (Aim 1). To elucidate the mechanism by which expression of mutant FUS induces NCT-related phenotypes, we will further probe the interactions between FUS and nuclear pore proteins, and test the hypothesis that abnormal phase transitions involving mutant FUS and nuclear pore proteins contribute to disrupted NCT (Aim 2). We also posit that impaired NCT induces toxicity via the mislocalization of transcripts and proteins, a notion that will be tested by using RNA-sequencing and proteomics to compare gene expression after cellular fractionation in mutant FUS versus control neurons, before and after manifestation of NCT-related phenotypes (Aim 3). Finally, we will test the therapeutic potential of targeting nuclear export in FUS human neurons and mice using strategies that have already been shown to be both safe and effective across multiple human diseases (Aim 4). This synergistic collaboration between two academic groups and an industrial partner (who will provide the therapeutic compound for studies in our laboratories) has the potential to uncover new mechanistic insights to disease and establish the therapeutic potential of targeting nucleocytoplasmic transport in ALS/FTD.