METHODS: To investigate gene splicing changes in early HD, we performed alternative splicing analyses coupled with a proteogenomics approach to identify early CAG length-associated splicing changes in an established isogenic HD cell model.
RESULTS: We report widespread neuronal differentiation stage- and CAG length-dependent splicing changes, and find an enrichment of RNA processing, neuronal function, and epigenetic modification-related genes with mutant HTT-associated splicing. When integrated with a proteomics dataset, we identified several of these differential splicing events at the protein level. By comparing with human post-mortem and mouse model data, we identified common patterns of altered splicing from embryonic stem cells through to post-mortem striatal tissue.
CONCLUSIONS: We show that widespread splicing dysregulation in HD occurs in an early cell model of neuronal development. Importantly, we observe HD-associated splicing changes in our HD cell model that were also identified in human HD striatum and mouse model HD striatum, suggesting that splicing-associated pathogenesis possibly occurs early in neuronal development and persists to later stages of disease. Together, our results highlight splicing dysregulation in HD which may lead to disrupted neuronal function and neuropathology.
BACKGROUND: This research is supported by the Lee Kong Chian School of Medicine, Nanyang Technological University Singapore Nanyang Assistant Professorship Start-Up Grant, the Singapore Ministry of Education under its Singapore Ministry of Education Academic Research Fund Tier 1 (RG23/22), the BC Children\'s Hospital Research Institute Investigator Grant Award (IGAP), and a Scholar Award from the Michael Smith Health Research BC.
方法:为了研究早期HD的基因剪接变化,在已建立的等基因HD细胞模型中,我们进行了选择性剪接分析和蛋白质基因组学方法,以鉴定早期CAG长度相关剪接变化.
结果:我们报道了广泛的神经元分化阶段和CAG长度依赖性剪接变化,发现RNA加工的富集,神经元功能,和具有突变HTT相关剪接的表观遗传修饰相关基因。当与蛋白质组学数据集整合时,我们在蛋白质水平上鉴定了几种差异剪接事件.通过与人类验尸和小鼠模型数据进行比较,我们确定了从胚胎干细胞到死后纹状体组织的剪接改变的常见模式。
结论:我们发现HD中广泛的剪接失调发生在神经元发育的早期细胞模型中。重要的是,我们在我们的HD细胞模型中观察到HD相关的剪接变化,这些变化也在人类HD纹状体和小鼠模型HD纹状体中被鉴定出来,提示剪接相关的发病机制可能发生在神经元发育的早期,并持续到疾病的后期。一起,我们的结果强调了HD的剪接失调,这可能导致神经元功能和神经病理学的破坏.
背景:这项研究得到了李孔川医学院的支持,南洋理工大学新加坡南洋助理教授创业补助金,新加坡教育部在其新加坡教育部学术研究基金一级(RG23/22)下,不列颠哥伦比亚省儿童医院研究所研究员授予奖(IGAP),和迈克尔·史密斯健康研究BC的学者奖。