ALS therapies and genomics for mutant TDP-43 and TLS/FUS

描述（由申请人提供）：该申请涉及两个广泛的挑战领域（15）转化科学，包括特定的挑战主题15- ns -104（早期治疗开发）和15- ns -103（“概念验证”的演示）和广泛的挑战领域（08）基因组学，特定的挑战主题03-NS-101（跨疾病研究，以确定低发病率孟德尔疾病和遗传复杂，高发病率疾病的共同机制）。肌萎缩侧索硬化症（ALS）是一种成人发病的神经退行性疾病，其上部和下部运动神经元的过早丧失导致致命的瘫痪，典型的病程为1至5年。在过去的15年里，大多数对ALS发病机制的研究都集中在普遍表达的超氧化物歧化酶（约占所有ALS病例的2%）突变引起的疾病上，但在过去的14个月里，由于发现两种非常相似的DNA/RNA结合蛋白——TAR DNA结合蛋白（TDP-43）和融合肉瘤（FUS/TLS）的突变也是ALS的主要原因，人们对ALS的理解发生了范式转变。在正常情况下，这两种蛋白都与RNA转录和选择性RNA剪接有关（FUS/TLS是剪接体的一个组成部分）。这提出了一种令人兴奋的可能性，即RNA代谢的改变，特别是选择性RNA剪接的错误，在ALS发病机制中起着至关重要的作用。随着人们进一步认识到含有TDP-43的细胞质内含物存在于绝大多数ALS散发性患者和包括额叶颞叶痴呆（FTD）在内的其他几种神经退行性疾病中，TDP-43的错误可能不仅是理解ALS疾病机制的核心，也是理解其他神经退行性疾病的核心。在此，我们建议1)结合转基因和基因靶向方法开发新的TDP-43和FUS/TLS介导的ALS小鼠模型；2)利用新开发的方法与高通量测序相结合，确定TDP-43和FUS/TLS在RNA代谢调节中的作用，作为了解其改变如何导致发病机制的手段，并为治疗开发寻找新的靶点。

DESCRIPTION (provided by applicant): This application addresses two Broad Challenge areas (15) Translational Science, including specific Challenge Topics 15-NS-104 (Early-stage therapy development) and 15-NS-103 (Demonstration of "proof-of-concept") and Broad Challenge area (08) Genomics, specific Challenge Topic 03-NS-101 (Cross-disease research to identify mechanisms common to Mendelian disorders of low incidence and genetically complex, high incidence disorders). Amyotrophic lateral sclerosis (ALS) is an adult-onset neurodegenerative disorder in which premature loss of upper and lower motor neurons leads to fatal paralysis with a typical disease course of one to five years. While most efforts to understand ALS pathogenesis over the last 15 years have focused on disease caused by mutation in the ubiquitously expressed superoxide dismutase (representing ~2% of all instances of ALS), during the past 14 months, a paradigm shift in understanding ALS has been initiated by discovery that mutations in two strikingly similar DNA/RNA binding proteins, TAR DNA-binding protein (TDP-43) and Fused in sarcoma (FUS/TLS), are also primary causes of ALS. In the normal context, both proteins have been linked to RNA transcription and alternative RNA splicing (FUS/TLS is an integral component of the spliceosome). This has raised the provocative possibility that alterations of RNA metabolism, especially errors of alternative RNA splicing, play a crucial role in ALS pathogenesis. With the further realization that TDP-43-containing cytoplasmic inclusions are found in the vast majority of ALS sporadic patients and in several other neurodegenerative diseases including Frontal Temporal Dementia (FTD), errors in TDP-43 may be central to understanding disease mechanism not just in ALS by also other neurodegenerative disorders. Here, we propose 1) to combine transgenic and gene- targeting approaches to develop new mouse models for TDP-43 and FUS/TLS mediated ALS and 2) to utilize newly developed methodologies linked to high-throughput sequencing to determine the role of TDP-43 and FUS/TLS in the regulation of RNA metabolism as a means to understand how their alterations underlie pathogenesis and to identify new targets for therapy development. PUBLIC HEALTH RELEVANCE: Over the last 14 months, a paradigm shift in understanding what goes wrong in the fatal motor neuron disease Amyotrophic Lateral Sclerosis has been initiated by the discoveries that mutations in a pair of RNA binding proteins (TDP-43 and FUS/TLS) are primary causes of the disease. Through construction and analysis of mice that are genetic mimics of these instances of inherited ALS, how these mutations cause premature death of the motor neurons will be identified. New, very high through put DNA/RNA sequencing methods will be used to identify genes whose expression is altered by the mutations, thereby identifying new targets and approaches for devising a successful therapy for ALS.