title: ETS-4 is a transcriptional regulator of life span in Caenorhabditis elegans.
abstract: Aging is a complex phenotype responsive to a plethora of environmental inputs; yet only a limited number of transcriptional regulators are known to influence life span. How the downstream expression programs mediated by these factors (or others) are coordinated into common or distinct set of aging effectors is an addressable question in model organisms, such as C. elegans. Here, we establish the transcription factor ETS-4, an ortholog of vertebrate SPDEF, as a longevity determinant. Adult worms with ets-4 mutations had a significant extension of mean life span. Restoring ETS-4 activity in the intestine, but not neurons, of ets-4 mutant worms rescued life span to wild-type levels. Using RNAi, we demonstrated that ets-4 is required post-developmentally to regulate adult life span; thus uncoupling the role of ETS-4 in aging from potential functions in worm intestinal development. Seventy ETS-4-regulated genes, identified by gene expression profiling of two distinct ets-4 alleles and analyzed by bioinformatics, were enriched for known longevity effectors that function in lipid transport, lipid metabolism, and innate immunity. Putative target genes were enriched for ones that change expression during normal aging, the majority of which are controlled by the GATA factors. Also, some ETS-4-regulated genes function downstream of the FOXO factor, DAF-16 and the insulin/IGF-1 signaling pathway. However, epistasis and phenotypic analyses indicate that ets-4 functioned in parallel to the insulin/IGF-1 receptor, daf-2 and akt-1/2 kinases. Furthermore, ets-4 required daf-16 to modulate aging, suggesting overlap in function at the level of common targets that affect life span. In conclusion, ETS-4 is a new transcriptional regulator of aging, which shares transcriptional targets with GATA and FOXO factors, suggesting that overlapping pathways direct common sets of lifespan-related genes.
authors.affiliation: Huntsman Cancer Institute, Department of Oncological Sciences, University of Utah, Salt Lake City, Utah, USA.
authors.forename: Bargavi
authors.initials: B
authors.lastname: Thyagarajan
authors.forename: Adam G
authors.initials: AG
authors.lastname: Blaszczak
authors.forename: Katherine J
authors.initials: KJ
authors.lastname: Chandler
authors.forename: Jennifer L
authors.initials: JL
authors.lastname: Watts
authors.forename: W Evan
authors.initials: WE
authors.lastname: Johnson
authors.forename: Barbara J
authors.initials: BJ
authors.lastname: Graves
mesh_terms: D000818:Animals; D001483:Base Sequence; D017173:Caenorhabditis elegans / Q000235:genetics* / Q000502:physiology*; D029742:Caenorhabditis elegans Proteins / Q000235:genetics* / Q000378:metabolism; D018509:DNA, Helminth / Q000378:metabolism; D051858:Forkhead Transcription Factors; D017353:Gene Deletion; D018507:Gene Expression Regulation, Developmental; D017238:Genes, Helminth / Q000235:genetics; D007328:Insulin / Q000378:metabolism; D007334:Insulin-Like Growth Factor I / Q000378:metabolism; D007413:Intestinal Mucosa / Q000378:metabolism; D007814:Larva / Q000254:growth & development / Q000378:metabolism; D008136:Longevity / Q000235:genetics*; D008957:Models, Genetic; D009154:Mutation / Q000235:genetics; D009928:Organ Specificity / Q000235:genetics; D010058:Oviposition / Q000235:genetics; D011485:Protein Binding; D015398:Signal Transduction / Q000235:genetics; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D014158:Transcription, Genetic
chemical_list: D029742:Caenorhabditis elegans Proteins; D018509:DNA, Helminth; C554612:ETS-4 protein, C elegans; D051858:Forkhead Transcription Factors; D007328:Insulin; D014157:Transcription Factors; C108831:daf-16 protein, C elegans; D007334:Insulin-Like Growth Factor I