Lifespan extension by differential translation mediated by eIF-4G in C. elegans

线虫中 eIF-4G 介导的差异翻译延长寿命

• 批准号: 8113756
• 负责人: ARIC N ROGERS
• 金额: $ 8.83万
• 依托单位: BUCK INSTITUTE FOR RESEARCH ON AGING
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-04-01 至 2013-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8113756
• 关键词: 3' Untranslated Regions; Accounting; Address; Aging; Alternative Splicing; Animal Model; Attenuated; Binding; Bioinformatics; Biological; Biological Assay; Biological Models; Caenorhabditis elegans; Candidate Disease Gene; Characteristics; Computers; Data Set; Development; Diabetes Mellitus; Disease; Eukaryotic Initiation Factor-4G; Frequencies; Gene Expression Profile; Genes; Genetic; Genetic Epistasis; Genetic Translation; Goals; Health; Human; Length; Life; Longevity; Longevity Pathway; Maintenance; Malignant Neoplasms; Mammals; Mass Spectrum Analysis; Mediating; Mentors; Mentorship; Messenger RNA; Methods; MicroRNAs; Modeling; Monitor; Nematoda; Nerve Degeneration; Open Reading Frames; Orthologous Gene; Play; Process; Protein Biosynthesis; Proteins; Proteome; RNA Splicing; Regulation; Regulatory Element; Reporter; Research; Resistance; Ribosomes; Role; Scientist; Sequence Analysis; Small RNA; Source; Starvation; Testing; Transcript; Transgenic Animals; Translating; Translation Initiation; Translations; Untranslated Regions; Yeasts; age related; aging gene; attenuation; base; biological adaptation to stress; cell type; computerized data processing; genetic manipulation; genome-wide; in vivo; information gathering; mRNA Expression; novel; overexpression; tool

DESCRIPTION (provided by applicant): Although inhibition of translation initiation extends lifespan from yeast to mammals, the mechanism remains unknown. We showed that one of the most robust lifespan extension comes from suppression of ifg-1, the C. elegans ortholog of eukaryotic translation initiation factor (eIF)-4G, a factor that positively regulates translation. Previous studies have analyzed changes in total mRNA expression to investigate causes of lifespan changes under a number of different genetic and environmental conditions. However, other studies have shown large discrepancies between the transcriptome and proteome. I used translation state array analysis (TSAA), which accounts for post-transcriptional processing, to investigate changes upon direct modulation of translation by inhibiting ifg-1 expression. A large number of differentially translated mRNAs were found and ontological analysis revealed that upregulated genes included stress response genes and aging genes that are positive regulators of aging. Preliminary sequence analysis suggests that genes with preferentially maintained expression contain conserved characteristics known to modulate translation. qRT- PCR and quantitative mass spectroscopy corroborate TSAA results. Hypothesis: in addition to reducing global rates of translation, suppression of ifg-1 results in preferential translation of mRNA associated with stress response and somatic maintenance based on mRNA composition. An epistasis screen of 50 translationally enhanced stress response genes showed 10 that are required for maximal lifespan extension when ifg-1 is inhibited. I intend to a) directly determine translation changes and the impact of overexpression for these seven genes using in vivo reporter constructs, b) analyze sequences for known or novel cis- regulatory elements and isolate microRNAs (miRNAs) associated with differentially translated mRNAs, and c) characterize the miRNA and cis-regulatory elements for their effects between conditions as well as their roles in lifespan modulation 7. PUBLIC HEALTH RELEVANCE: Inhibition of translation extends lifespan across species. Simple model organisms like the nematode C. elegans provide powerful tools to uncover biological mechanisms that determine the beneficial effects of translation inhibition. Using C. elegans, I will examine how post-transcriptional processing is remodeled upon inhibition of translation initiation through the C. elegans ortholog of eukaryotic translation initiation factor 4G. Given the role played by deregulation of translation in age-related diseases including diabetes, cancer and neurodegeneration, this research has important implications for human health.

描述（由申请人提供）：尽管对翻译起始的抑制作用延长了寿命从酵母到哺乳动物，但该机制仍然未知。我们表明，最强大的寿命扩展之一来自对真核翻译起始因子（EIF）-4G的IFG-1的抑制，这是一个积极调节翻译的因素。先前的研究已经分析了总mRNA表达的变化，以研究许多不同遗传和环境条件下的寿命变化原因。但是，其他研究表明转录组和蛋白质组之间存在巨大差异。我使用翻译状态阵列分析（TSAA），该分析解释了转录后处理，通过抑制IFG-1表达来调查直接调节翻译的变化。发现大量差异翻译的mRNA，本体论分析表明，上调的基因包括应激反应基因和衰老基因，这些基因是衰老的阳性调节剂。初步序列分析表明，具有优先维持表达的基因包含已知可以调节翻译的保守特征。 QRT-PCR和定量质谱证实了TSAA结果。假设：除了降低全球翻译速率外，IFG-1的抑制还会导致基于mRNA组成的压力反应和躯体维持相关的mRNA的优先翻译。抑制IFG-1时最大寿命延长所必需的50个翻译应力反应基因的上学筛选显示10个。我打算a）直接确定使用体内报告基因构建体对这七个基因的翻译变化以及过表达的影响，b）分析序列的已知或新颖的顺式调节元素和与差分翻译的mRNA和c相关的分离型构造元件和分离的microRNA（miRNA），以及miRNA和CIS调控元素的效果7的序列，并在其效果下以及其效应范围以及其效果及其效果以及效果以及效果效果以及效果的效果。 公共卫生相关性：抑制翻译会延长跨物种的寿命。诸如线虫C.秀丽隐杆线虫之类的简单模型生物提供了强大的工具来发现决定翻译抑制的有益作用的生物学机制。使用秀丽隐杆线虫，我将研究通过秀丽隐杆线虫直系同源物的真核翻译起始因子4G抑制翻译起始后的转录后处理。鉴于对年龄相关疾病（包括糖尿病，癌症和神经退行性的）疾病中翻译的作用起作用，这项研究对人类健康具有重要意义。