Disruption of nucleocytoplasmic transport in FUS-related neurodegenerative diseases

最近出现了蛋白质和RNA通过核孔的核质转运受损（NCT） 作为神经退化的中枢机制事实上，我们最近已经表明，突变亨廷顿蛋白显着 加剧衰老相关的核完整性改变和NCT破坏，以及核孔介导的 在C9 ORF 72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FUS的表达，一种与ALS和FTD相关的蛋白质，导致细胞核的丢失， 孔完整性，改变的核膜形态和其他表型相关的破坏NCT在多个，相关 包括同基因人类神经元和一种新的FUS基因敲入小鼠模型。在这个项目中，我们将进一步 在ALS和FTD中，使用以下方法询问疾病相关FUS和NCT受损之间的关系： 上述模型系统和人CNS组织（目的1）。为了阐明表达的机制， 突变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，并测试的假设，异常相变涉及突变FUS和核孔蛋白 有助于破坏NCT（目标2）。我们还证实，受损的NCT诱导毒性通过错误定位的 转录物和蛋白质，这一概念将通过使用RNA测序和蛋白质组学来比较基因表达来进行测试 在突变FUS与对照神经元的细胞分级后，在NCT相关的表现之前和之后， 表型（目标3）。最后，我们将测试靶向FUS人类神经元核输出的治疗潜力， 小鼠使用已经被证明对多种人类疾病安全有效的策略（目标4）。 两个学术团体和一个工业合作伙伴（将提供治疗药物）之间的协同合作 在我们的实验室研究的化合物）有可能揭示新的机制见解的疾病和建立 ALS/FTD中靶向核质转运的治疗潜力。

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.