Project description:Analysis of gene expression in two long-lived daf-2 mutant (mutation in the insulin/IGF-1 receptor) and eat-2 mutant (caloric restriction model), comparison of gene expression profiles of two long-lived mutants provide novel insight into longevity Impaired insulin/IGF-1 signaling (IIS) pathway and caloric restriction (CR) are two well-established interventions to prolong lifespan in worm C. elegans. Although many studies using “-omics” approaches have gained informative knowledges on key longevity regulators in either IIS or CR models, few of those investigated the shared regulators between these two longevity interventions and integrated the messages from different –omics studies. In this study, we aimed to identify key pathways and metabolite fingerprints of longevity shared between the two interventions in worms using a multi-omics integration approach. We collected transcriptomics and metabolomics data from two long-lived mutant worm strains, i.e. daf-2 (impaired IIS pathway) and eat-2 (CR model) and compared with N2 strain. We detected many key pathways that were upregulated at the gene expression level in both long-lived mutants, such as defense response and lipid storage, while synthesis of macromolecules and developmental processes were downregulated at the transcript level. From our polar metabolite analysis, we discovered several shared metabolic features between the two long-lived mutants, including glycerol-3P, adenine, xanthine and AMP. In addition, we detected a lowered amino acid pool and two fatty acid species, C18:0 and C17:1, that behaved similarly in both long-lived mutants. After we integrated transcriptomics and metabolomics data based on the annotations in KEGG, our results highlighted a downregulation of pyrimidine metabolism and upregulation of purine metabolism in both long-lived mutants compared to N2 worms. Overall, our findings point towards the existence of shared metabolic pathways that are important for lifespan extension and provide novel insight of potential regulators and metabolic fingerprints for longevity.
Project description:In order to get an insight into the complex interplay of miRNAs in insulin signaling, we profiled the small RNA polulation of daf-2(e1370) worms at young adult stage by Next Generation sequencing. We performed Next Generation sequencing to compare miRNA profiles of wild-type and long-lived daf-2(e1370) mutant at young adult stage
Project description:Analysis of gene expression in long-lived daf-2 mutants for the insulin/IGF-1 receptor. daf-2(e1370) and daf-2(m577) alleles each examined as single and as double mutations with the daf-16(df50) allele. DAF-2 regulates DAF-16, a transcription factor. Results provide insight into longevity.
Project description:To exmine the role of nonsense-mediated mRNA decay process in the longevity regulation of daf-2 mutants, we sequenced transcriptomes from day 1 adult Caenorhabditis elegans: Bristol N2 (wild-type), and smg-2(qd101), daf-2(e1370) and smg-2(qd101); daf-2(e1370) mutants.
Project description:Transcriptional profiling of day 1 animals comparing untreated daf-2(-) animals and daf-2(-) xbp-1(-) animals. Goal was to identify genes whose expression in daf-2 mutants is dependent (directly or indirectly) on xbp-1. Two-condition experiment, daf-2(-) animals and daf-2(-) xbp-1(-) animals. 4 Biological replicates in daf-2(e1370) background: 4 sets of daf-2(e1370) animals and their matching daf-2(e1370) xbp-1(zc12) animals. 4 Biological replicates in daf-2(e1368) background: 4 sets of daf-2(e1368) animals and their matching daf-2(e1368) xbp-1(zc12) animals.
Project description:FoxO transcription factors promote longevity across taxa. How they do so is poorly understood. In the nematode Caenorhabditis elegans, the A- and F-isoforms of the FoxO transcription factor DAF-16 extend life span in the context of reduced DAF-2 insulin-like growth factor receptor (IGFR) signaling. To elucidate the mechanistic basis for DAF-16/FoxO-dependent life span extension, we performed an integrative analysis of isoform-specific daf-16/FoxO mutants. In contrast to previous studies suggesting that DAF-16F plays a more prominent role in life span control than DAF-16A, isoform-specific daf-16/FoxO mutant phenotypes and whole transcriptome profiling revealed a predominant role for DAF-16A over DAF-16F in life span control, stress resistance, and target gene regulation. Integration of these data sets enabled the prioritization of a subset of 92 DAF-16/FoxO target genes for functional interrogation. Among 29 genes tested, two DAF-16A-specific target genes significantly influenced longevity. Our discovery of new longevity genes underscores the efficacy of our integrative strategy while providing a general framework for identifying specific downstream gene regulatory events that contribute substantially to transcription factor functions. As FoxO transcription factors have conserved functions in promoting longevity and may be dysregulated in aging-related diseases, these findings promise to illuminate fundamental principles underlying aging in animals. Whole-transcriptome profiling of daf-16/FoxO isoform-specific deletion mutants in the long-lived daf-2(e1370) background. Included are daf-16 wild-type, daf-16 null mutation, daf-16a/f mutation, two independent daf-16a mutations, and daf-16f mutation. N2 wild-type controls are also included.
Project description:In order to understand the complexity of gene regulation downstream of IIS, we did RNA-seq in mixed culture in wild-type, daf-2(e1370), daf-16(mgDf50);daf-2(e1370) and daf-2(e1370);daf-12(m20 and correlated it with ChIP-seq data
Project description:Long-lived genetic mutants from different pathways of lifespan extension were used to determine the extent to which there are common downstream mediators of longevity. We have previously obtained RNA-sequencing data from other long-lived mutants including sod-2, clk-1, isp-1, nuo-6 and daf-2. Gene expression will be compared between these nine long-lived mutants.