Upstream open reading frames in neuronal function: a singular and genome-wide approach

神经元功能中的上游开放阅读框：单一的全基因组方法

• 批准号: 9234082
• 负责人: Caitlin Marie Rodriguez
• 金额: $ 3.47万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-03-01 至 2018-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9234082
• 关键词: 5' Untranslated Regions; Agonist; Area; Autistic Disorder; Biochemical; Bioinformatics; Biological Models; Biology; CGG repeat; Case Study; Cell Line; Clinical; Codon Nucleotides; Data; Disease; Emerging Technologies; Event; FMR1; FMR1 repeat; FMRP; FXTAS; Fragile X Syndrome; Future; Genes; Goals; Grant; Intellectual functioning disability; Intervention; Lead; Learning; Maps; Measures; Mediating; Memory; Messenger RNA; Nerve Degeneration; Neurobiology; Neurodegenerative Disorders; Neurodevelopmental Disorder; Neurons; Nucleotides; Open Reading Frames; Pathogenesis; Play; Positioning Attribute; Prevalence; Process; Production; Protein Biosynthesis; Proteins; RNA; Reporter; Research; Ribosomes; Role; Scanning; Series; Site; Stream; Structure; Synaptic plasticity; Techniques; Testing; Training; Transcript; Translating; Translational Regulation; Translations; Work; base; career; cellular imaging; channel blockers; gene product; genome-wide; insight; kainate; nervous system disorder; neuroblastoma cell; next generation sequencing; novel; polyglycine; public health relevance; response; ribosome profiling; synaptic function; transcriptome

 DESCRIPTION (provided by applicant): Neurons regulate when and where they synthesize new proteins to maintain basal and activity-dependent compartmental fidelity. Control of this process is largely regulated at translational initiation which typically occurs at the 5'-most AUG codon in an appropriate mRNA sequence context. Emerging data in simple model systems suggests that un-annotated, upstream open reading frames (uORFs) are utilized on a significant fraction of all transcripts. These uORFs often initiate at near-AUG (one base different from AUG) codons and display condition-dependent usage, suggesting they may play a regulatory role in translational control. How such atypical initiation events are mediated and what roles they play in neuronal function and disease are unknown. The central hypothesis of this grant is that upstream open reading frame usage is an important regulator of translational dynamics in neurons, and that proteins produced by translation from un-annotated uORFs will contribute to neuronal function. Our group recently discovered a novel mechanism for protein translational initiation associated with nucleotide repeats in the neurodegenerative disorder Fragile X-associated Tremor Ataxia Syndrome (FXTAS). FXTAS results from a CGG nucleotide repeat expansion in the 5' untranslated region (UTR) of the FMR1 gene. We discovered that this repeat expansion elicits initiation at a near-AUG codon in the 5'UTR, resulting in translation through the repeat via a process known as RAN (Repeat Associated Non-AUG) translation. This translation event leads to synthesis of a poly-glycine containing protein, FMRpolyG, even at normal repeat sizes. This proposal will first determine when FMRpolyG is synthesized in neurons both basally and in response to activity. Further, the impact of FMRpolyG synthesis on translation of the major FMR1 gene product, FMRP- a protein implicated in autism and intellectual disability will be assessed. To determine the prevalence of similar uORF utilization events in neurons, the novel next-generation sequencing technique known as ribosomal profiling will be used to measure ribosomal occupancy within 5'UTRs across the neuronal transcriptome. These studies will employ cellular imaging, biochemical and bioinformatics techniques to explore a new area in neurobiology with relevance to both synaptic plasticity as well as numerous neurological diseases.

 描述（由适用提供）：神经元调节何时何地合成新蛋白质以维持基本和活动依赖性的隔室保真度。对此过程的控制在很大程度上受到翻译起始的调节，通常在适当的mRNA序列上下文中发生在最高的8月密码子上。简单模型系统中的新兴数据表明，未经通知的上游开放式阅读框（UORF）用于所有转录本的很大一部分。这些UORF通常是在附近的（一个不同于Aug）的密码子（一个基部）启动，并显示与条件有关的用法，这表明它们可能在翻译控制中起调节作用。这种非典型倡议事件是如何调节的以及它们的角色 在神经元功能和疾病中发挥作用是未知的。这项赠款的中心假设是，上游开放的阅读框架用法是神经元转化动力学的重要调节剂，而未经宣传的UORF的翻译产生的蛋白质将有助于神经元功能。我们的小组最近发现了一种与神经退行性疾病中核丁基重复序列相关的蛋白质转化倡议的新机制，易碎X相关性共济失调综合征（FXTAS）。 FXTA是由FMR1基因的5'未翻译区域（UTR）中的CGG核苷酸重复扩张引起的。我们发现，这种重复扩展在5'UTR中的近调密码子上引发了主动性，从而通过 通过称为ran（重复相关的非aug）翻译的过程重复。即使在正常重复大小下，这种翻译事件也会导致含有蛋白质fmrpolyg的多聚甘氨酸的合成。该建议将首先确定何时基本和响应活动中的神经元合成FMRPolyg。此外，将评估FMRPolyg合成对自闭症和智力障碍实施的主要FMR1基因产物翻译的影响。为了确定神经元中类似的UORF利用事件的患病率，新型的下一代测序技术称为核糖体分析将用于测量整个神经元转录组5'UTRS内的核糖体占用率。这些研究将采用细胞成像，生化和生物信息学技术来探索与突触可塑性以及许多神经系统疾病相关的神经生物学领域的新领域。