Project 1

项目总结/摘要：项目1 C9 orf 72基因中的六核苷酸（G4 C2）重复扩增是最常见的遗传原因， 肌萎缩侧索硬化症（ALS）和额颞叶痴呆（FTD），统称为c9 ALS/FTD。 越来越多的证据表明，含有重复序列的转录本通过功能获得引起c9 ALS/FTD 通过产生有毒的RNA焦点和二肽重复（DPR）蛋白的机制。我们的核心假设是 建议这些病理（RNA灶，DPR蛋白）中的每一种都是共同的和细胞特异性的 分子级联为了解决这个问题，我们将进行批量和单核RNAseq（sn-RNAseq） 使用我们的新型c9 ALS/FTD小鼠模型和患者组织来揭示整个和单细胞景观 在c9 ALS发病过程中发生的转录变化。我们的单核方法也将允许 我们来测试具有RNA灶和/或DPR蛋白病理学的单个神经元与甚至具有RNA灶和/或DPR蛋白病理学的单个神经元相比是如何不同的。 邻近神经元无明显病变。此外，我们将用以下药物治疗我们的c9 ALS/FTD小鼠模型： 反义寡核苷酸（阿索）靶向含重复序列的转录本，已显示可减少 各种c9 ALS模型中的RNA病灶负荷、DPR蛋白病理学和其他异常。治疗将 在疾病的早期和晚期开始，以确定阿索治疗的最佳时机， 神经病理学、行为缺陷和转录变化的单细胞景观。我们的研究将 确定和验证治疗c9 ALS/FTD的高价值治疗靶点。

PROJECT SUMMARY/ABSTRACT: PROJECT 1 A hexanucleotide (G4C2) repeat expansion in the C9orf72 gene is the most common genetic cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD), collectively referred to as c9ALS/FTD. Mounting evidence indicates repeat-containing transcripts cause c9ALS/FTD through gain-of-function mechanisms by producing toxic RNA foci and dipeptide repeat (DPR) proteins. Our central hypothesis in this proposal is that each of these pathologies (RNA foci, DPR proteins) elicits both common and cell-specific molecular cascades. To address this question, we will perform bulk and single-nucleus RNAseq (sn-RNAseq) using our novel c9ALS/FTD mouse model and patient tissues to uncover the whole and single-cell landscape of transcriptional changes that occur during c9ALS pathogenesis. Our single-nucleus approach will also allow us to test how an individual neuron with RNA foci and/or DPR protein pathology is different than even a neighboring neuron without apparent pathology. Moreover, we will treat our c9ALS/FTD mouse model with antisense oligonucleotides (ASO) targeting repeat-containing transcripts, which has been shown to reduce RNA foci burden, DPR protein pathology and other anomalies in various c9ALS models. Treatment will be initiated at early and late stages of disease to determine the optimal timing of ASO treatment for mitigating neuropathology, behavioral deficits, and the single-cell landscape of transcriptional changes. Our studies will identify and validate high value therapeutic targets to treat c9ALS/FTD.