title: Modulated microRNA expression during adult lifespan in Caenorhabditis elegans.
abstract: MicroRNAs (miRNAs) are small, abundant transcripts that can bind partially homologous target messages to inhibit their translation in animal cells. miRNAs have been shown to affect a broad spectrum of biological activities, including developmental fate determination, cell signaling and oncogenesis. Little is known, however, of miRNA contributions to aging. We examined the expression of 114 identified Caenorhabditis elegans miRNAs during the adult lifespan and find that 34 miRNAs exhibit changes in expression during adulthood (P<or= 0.05), 31 with more than a twofold level change. The majority of age-regulated miRNAs decline in relative abundance as animals grow older. Expression profiles of developmental timing regulators lin-4 and let-7 miRNAs, as well as conserved muscle miRNA miR-1, show regulation during adulthood. We also used bioinformatic approaches to predict miRNA targets encoded in the C. elegans genome and we highlight candidate miRNA-regulated genes among C. elegans genes previously shown to affect longevity, genes encoding insulin-like ligands, and genes preferentially expressed in C. elegans muscle. Our observations identify miRNAs as potential modulators of age-related decline and suggest a general reduction of message-specific translational inhibition during aging, a previously undescribed feature of C. elegans aging. Since many C. elegans age-regulated miRNAs are conserved across species, our observations identify candidate age-regulating miRNAs in both nematodes and humans.
authors.affiliation: Department of Molecular Biology and Biochemistry, Rutgers, The State University of New Jersey, Nelson Biological Laboratories, 604 Allison Road, Piscataway NJ 08854, USA.
authors.forename: Carolina
authors.initials: C
authors.lastname: Ibáñez-Ventoso
authors.forename: Maocheng
authors.initials: M
authors.lastname: Yang
authors.forename: Suzhen
authors.initials: S
authors.lastname: Guo
authors.forename: Harlan
authors.initials: H
authors.lastname: Robins
authors.forename: Richard W
authors.initials: RW
authors.lastname: Padgett
authors.forename: Monica
authors.initials: M
authors.lastname: Driscoll
mesh_terms: D000818:Animals; D017173:Caenorhabditis elegans / Q000235:genetics* / Q000502:physiology*; D029742:Caenorhabditis elegans Proteins / Q000235:genetics; D005786:Gene Expression Regulation; D006262:Health; D007328:Insulin / Q000235:genetics; D008136:Longevity / Q000235:genetics* / Q000502:physiology; D035683:MicroRNAs / Q000235:genetics* / Q000302:isolation & purification; D018482:Muscle, Skeletal / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D012097:Repressor Proteins / Q000235:genetics; D013997:Time Factors
chemical_list: D029742:Caenorhabditis elegans Proteins; D007328:Insulin; D035683:MicroRNAs; D012333:RNA, Messenger; D012097:Repressor Proteins; C474488:let-7 microRNA, C elegans; C452194:lin-4 microRNA, C elegans