Dataset Information

Identification of DAF-16/FoxO targets associated with longevity

ABSTRACT: FoxO transcription factors can promote longevity in invertebrates and mammals. In C.elegans, the FoxO family member DAF-16 is required for lifespan extension in the contexts of daf-2/IGFR mutation and germline ablation. The daf-16 genomic locus encodes three distinct groups of transcripts (a,b, and d/f/h). In animals with reduced insulin signaling or ablated germlines, mutations that reduce daf-16a and d/f/h levels without affecting daf-16b reduce lifespan to the same extent as daf-16 null mutations. We reasoned that identifying a set of targets of the daf-16a and d/f/h isoforms that are differentially regulated in two contexts of reduced insulin signaling and in germline ablated animals would enrich for the daf-16 transcriptional targets that are required for longevity. We identified targets that were differentially regulated in daf-2(e1368) and daf-2(e1370) mutants relative to wild-type, and differentially regulated in the opposite direction from WT in compound mutants with both daf-16(mg54), which eliminates the a and d/f/h isoforms, and daf-16(mu86) which is a predicted null allele. We performed a similar analysis in glp-1(e2141) germline ablated animals (omitting the wild-type comparison). We then identified daf-16 targets associated with longevity (dal genes) which were found in all three sets of comparisons.

ORGANISM(S): Caenorhabditis elegans

PROVIDER: GSE111338 | GEO | 2019/03/01

REPOSITORIES: GEO

ACCESS DATA

Similar Datasets

Project description:Post-embryonic development of the nematode C. elegans is governed by nutrient availability. L1-stage larvae remain in a state of developmental arrest after hatching until they feed. This “L1 arrest” (or "L1 diapause") is associated with increased stress resistance, supporting starvation survival. Loss of the transcription factor daf-16/FOXO, an effector of insulin/IGF signaling, results in arrest-defective and starvation-sensitive phenotypes. We show that daf-16/FOXO regulates L1 arrest cell-nonautonomously, suggesting that insulin/IGF signaling regulates at least one additional signaling pathway. We used mRNA-seq to identify candidate signaling molecules affected by daf-16/FOXO during L1 arrest. daf-16/FOXO had overlapping but distinct effects on gene expression in L1 arrest compared to daf-2/InsR adults. Notably, dbl-1/TGF-β, a ligand for the Sma/Mab pathway, and daf-36, which encodes an upstream component of the daf-12/NHR steroid hormone signaling pathway, were up-regulated during L1 arrest in a daf-16/FOXO mutant. Using genetic epistasis analysis, we show that dbl-1/TGF-β and daf-12/NHR steroid hormone signaling pathways are required for the daf-16/FOXO arrest-defective phenotype, suggesting that daf-16/FOXO represses dbl-1/TGF-β and daf-36. The dbl-1/TGF-β and daf-12/NHR pathways have not previously been shown to affect L1 development, but we found that disruption of these pathways delayed L1 development in fed larvae, consistent with these pathways promoting development in starved daf-16/FOXO mutants. Though the dbl-1/TGF-β and daf-12/NHR pathways are epistatic to daf-16/FOXO for the arrest-defective phenotype, disruption of these pathways does not suppress starvation sensitivity of daf-16/FOXO mutants. This observation uncouples starvation survival from developmental arrest, indicating that DAF-16/FOXO targets distinct effectors for each phenotype, and revealing that inappropriate development during starvation does not cause the early demise of daf-16/FOXO mutants. Overall, this study shows that daf-16/FOXO promotes developmental arrest cell-nonautonomously by repressing pathways that promote larval development.

Dataset Information

Identification of DAF-16/FoxO targets associated with longevity

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure