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: 8601960
• 负责人: ARIC N ROGERS
• 金额: $ 24.88万
• 依托单位: MOUNT DESERT ISLAND BIOLOGICAL LAB
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-02-01 至 2016-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8601960
• 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; abstracting; age related; aging gene; attenuation; base; biological adaptation to stress; cell type; computerized data processing; deep sequencing; genetic manipulation; genome-wide; in vivo; information gathering; mRNA Expression; novel; overexpression; tool

6. Project Summary / Abstract 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 preferrentially 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.

6. 项目摘要/摘要