Mechanisms regulating tau alternative pre-mRNA splicing

描述（由申请人提供）：调节tau替代pre-mRNA剪接的机制越来越多的证据表明，pre-mRNA剪接缺陷和异常剪接导致一系列神经退行性疾病。选择性剪接对tau基因的功能至关重要，人类tau基因的剪接突变导致额颞叶痴呆（FTLD-tau）。虽然1998年首次报道了tau剪接突变，但突变影响tau选择性剪接的机制仍然知之甚少，FTLD-tau的风险因素和遗传修饰因子仍有待确定。本研究旨在探讨tau基因选择性剪接的调控机制。我们计划使用分子、生化和细胞生物学方法来研究tau蛋白的选择性剪接，并比较野生型和突变型tau蛋白转录本的剪接体识别差异。我们建立了体外生化分析和细胞培养系统来研究tau外显子10的选择性剪接。利用生化分析和表达克隆策略，我们在初步研究中发现了几个参与tau外显子10选择性剪接的蛋白质。还建立了一个初级神经元培养系统，以研究已确定的因素在神经元细胞死亡中的作用。对tau选择性剪接重要的顺式和反式元件的分子解剖不仅有助于理解控制tau选择性剪接的基本机制，而且有助于揭示神经变性发病机制的新参与者。我们计划使用生物信息学、生化、分子和遗传学相结合的方法来研究FTLD-tau这一最常见的神经退行性疾病的发病机制。

DESCRIPTION (provided by applicant): Mechanisms regulating tau alternative pre-mRNA splicing Accumulating evidence indicates that pre-mRNA splicing defects and aberrant splicing lead to a range of neurodegenerative disorders. Alternative splicing is critical for tau gene function, and splicing mutations in the human tau gene lead to fronto-temporal lobe dementia (FTLD-tau). Although tau splicing mutations were initially reported in 1998, the mechanisms by which mutations affect tau alternative splicing are still poorly understood, and risk factors as well as genetic modifiers in FTLD-tau remain to be identified. This proposal aims to investigate the mechanisms regulating tau gene alternative splicing. We plan to use molecular, biochemical and cell biological methods to investigate tau alternative splicing and to compare the differential spliceosomal recognition of wild type versus mutant tau transcripts. We have established both in vitro biochemical assays and cell culture systems to investigate tau exon 10 alternative splicing. Using biochemical assays and an expression cloning strategy, we have identified several proteins involved in tau exon 10 alternative splicing in our preliminary studies. A primary neuronal culture system has also been set up to investigate the role of identified factors in neuronal cell death. Molecular dissection of cis- and trans-acting elements important for tau alternative splicing will not only help in understanding the basic mechanisms controlling tau alternative splicing but also reveal new players in pathogenesis of neurodegeneration. We plan to use combined bioinformatics, biochemical, molecular and genetic approaches to study the pathogenetic mechanisms underlying FTLD-tau, one most common neurodegenerative disorders. PUBLIC HEALTH RELEVANCE: Overwhelming evidence supports that aberrant RNA processing plays an important role in the pathogenesis of neurodegeneration, including tauopathy, a common neurological disease. Splicing mutations affecting tau pre-mRNA splicing lead to tauopathy, however, the majority of tauopathy patients show disturbance in tau pre-mRNA splicing regulation without detectable mutations in the tau gene. The mechanisms by which mutations affect tau alternative splicing are poorly understood, and risk factors as well as genetic modifiers in tauopathy remain to be identified. Based on published work and our preliminary studies, we propose to use a combined molecular, biochemical and cell biological approach to investigate how mutations affecting tau alternative splicing and to identify possible risk factors or genetic modifiers that contribute to pathogenesis of tauopathy.