title: Circadian deep sequencing reveals stress-response genes that adopt robust rhythmic expression during aging.
abstract: Disruption of the circadian clock, which directs rhythmic expression of numerous output genes, accelerates aging. To enquire how the circadian system protects aging organisms, here we compare circadian transcriptomes in heads of young and old Drosophila melanogaster. The core clock and most output genes remained robustly rhythmic in old flies, while others lost rhythmicity with age, resulting in constitutive over- or under-expression. Unexpectedly, we identify a subset of genes that adopted increased or de novo rhythmicity during aging, enriched for stress-response functions. These genes, termed late-life cyclers, were also rhythmically induced in young flies by constant exposure to exogenous oxidative stress, and this upregulation is CLOCK-dependent. We also identify age-onset rhythmicity in several putative primary piRNA transcripts overlapping antisense transposons. Our results suggest that, as organisms age, the circadian system shifts greater regulatory priority to the mitigation of accumulating cellular stress.
authors.affiliation: Department of Biochemistry &Biophysics, 2011 Agriculture &Life Sciences Building, Oregon State University, Corvallis, Oregon 97331, USA.
authors.forename: Rachael C
authors.initials: RC
authors.lastname: Kuintzle
authors.affiliation: Department of Integrative Biology, 3029 Cordley Hall, Oregon State University, Corvallis, Oregon 97331, USA.
authors.forename: Eileen S
authors.initials: ES
authors.lastname: Chow
authors.affiliation: Department of Integrative Biology, 3029 Cordley Hall, Oregon State University, Corvallis, Oregon 97331, USA.
authors.forename: Tara N
authors.initials: TN
authors.lastname: Westby
authors.affiliation: Department of Integrative Biology, 3029 Cordley Hall, Oregon State University, Corvallis, Oregon 97331, USA.
authors.forename: Barbara O
authors.initials: BO
authors.lastname: Gvakharia
authors.affiliation: Department of Integrative Biology, 3029 Cordley Hall, Oregon State University, Corvallis, Oregon 97331, USA.
authors.forename: Jadwiga M
authors.initials: JM
authors.lastname: Giebultowicz
authors.affiliation: Department of Biochemistry &Biophysics, 2011 Agriculture &Life Sciences Building, Oregon State University, Corvallis, Oregon 97331, USA.|School of Electrical Engineering and Computer Science, 1148 Kelley Engineering Center, Oregon State University, Corvallis, Oregon 97331, USA.
authors.forename: David A
authors.initials: DA
authors.lastname: Hendrix
mesh_terms: D000222:Adaptation, Physiological / Q000235:genetics*; D000375:Aging / Q000235:genetics*; D000818:Animals; D057906:Circadian Clocks / Q000235:genetics; D002940:Circadian Rhythm / Q000235:genetics*; D029721:Drosophila Proteins / Q000235:genetics; D004331:Drosophila melanogaster / Q000235:genetics*; D063990:Gene Ontology; D017344:Genes, Insect / Q000235:genetics; D059014:High-Throughput Nucleotide Sequencing / Q000379:methods*; D018384:Oxidative Stress; D059467:Transcriptome
chemical_list: D029721:Drosophila Proteins