title: RPD3 histone deacetylase and nutrition have distinct but interacting effects on Drosophila longevity.
abstract: Single-gene mutations that extend longevity have revealed regulatory pathways related to aging and longevity. RPD3 is a conserved histone deacetylase (Class I HDAC). Previously we showed that Drosophila rpd3 mutations increase longevity. Here we tested the longevity effects of RPD3 on multiple nutrient levels. Dietary restriction (DR) has additive effects on RPD3-mediated longevity extension, but the effect may be modestly attenuated relative to controls. RPD3 and DR therefore appear to operate by distinct but interacting mechanisms. Since RPD3 regulates transcription, the mRNA levels for two proteins involved in nutrient signaling, 4E-BP and Tor, were examined in rpd3 mutant flies. 4E-BP mRNA was reduced under longevity-increasing conditions. Epistasis between RPD3 and 4E-BP with regard to longevity was then tested. Flies only heterozygous for a mutation in Thor, the 4E-BP gene, have modestly decreased life spans. Flies mutant for both rpd3 and Thor show a superposition of a large RPD3-mediated increase and a small Thor-mediated decrease in longevity at all food levels, consistent with each gene product having distinct effects on life span. However, DR-mediated extension was absent in males carrying both mutations and lessened in females. Our results support the view that multiple discrete but interacting mechanisms regulate longevity.
authors.affiliation: Department of Biology, University of Hartford, West Hartford, CT 06117, USA.
authors.forename: Stewart
authors.initials: S
authors.lastname: Frankel
authors.affiliation: Department of Genetics and Genome Sciences, School of Medicine, University of Connecticut Health, Farmington, CT 06030, USA.
authors.forename: Jared
authors.initials: J
authors.lastname: Woods
authors.affiliation: Department of Genetics and Genome Sciences, School of Medicine, University of Connecticut Health, Farmington, CT 06030, USA.|Current address: Division of Pediatric Endocrinology, Department of Pediatrics, Faculty of Health Sciences, McMaster University, Ontario, Canada.
authors.forename: Tahereh
authors.initials: T
authors.lastname: Ziafazeli
authors.affiliation: Department of Genetics and Genome Sciences, School of Medicine, University of Connecticut Health, Farmington, CT 06030, USA.|Institute for Systems Genomics, School of Medicine, University of Connecticut Health, Farmington, CT 06030, USA.
authors.forename: Blanka
authors.initials: B
authors.lastname: Rogina
mesh_terms: D000821:Animal Feed; D000818:Animals; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism*; D004331:Drosophila melanogaster / Q000201:enzymology / Q000235:genetics / Q000378:metabolism*; D005260:Female; D005786:Gene Expression Regulation / Q000502:physiology*; D005838:Genotype; D056284:Histone Deacetylase 1 / Q000235:genetics / Q000378:metabolism*; D008136:Longevity / Q000235:genetics / Q000502:physiology*; D008297:Male; D009154:Mutation; D015398:Signal Transduction
chemical_list: D029721:Drosophila Proteins; C512966:HDAC1 protein, Drosophila; D056284:Histone Deacetylase 1
keywords: Drosophila; Rpd3; aging; dietary restriction; longevity