title: Circadian regulation of olfaction and an evolutionarily conserved, nontranscriptional marker in Caenorhabditis elegans.
abstract: Circadian clocks provide a temporal structure to processes from gene expression to behavior in organisms from all phyla. Most clocks are synchronized to the environment by alternations of light and dark. However, many organisms experience only muted daily environmental cycles due to their lightless spatial niches (e.g., caves or soil). This has led to speculation that they may dispense with the daily clock. However, recent reports contradict this notion, showing various behavioral and molecular rhythms in Caenorhabditis elegans and in blind cave fish. Based on the ecology of nematodes, we applied low-amplitude temperature cycles to synchronize populations of animals through development. This entrainment regime reveals rhythms on multiple levels: in olfactory cued behavior, in RNA and protein abundance, and in the oxidation state of a broadly conserved peroxiredoxin protein. Our work links the nematode clock with that of other clock model systems; it also emphasizes the importance of daily rhythms in sensory functions that are likely to impact on organism fitness and population structure.
authors.affiliation: Department of Molecular Chronobiology, Faculty of Mathematics and Natural Science, University of Groningen, 9474 AG Groningen, The Netherlands. maria.olmedo@med-uni.muenchen.de
authors.forename: Maria
authors.initials: M
authors.lastname: Olmedo
authors.forename: John S
authors.initials: JS
authors.lastname: O'Neill
authors.forename: Rachel S
authors.initials: RS
authors.lastname: Edgar
authors.forename: Utham K
authors.initials: UK
authors.lastname: Valekunja
authors.forename: Akhilesh B
authors.initials: AB
authors.lastname: Reddy
authors.forename: Martha
authors.initials: M
authors.lastname: Merrow
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D017173:Caenorhabditis elegans / Q000235:genetics* / Q000502:physiology*; D029742:Caenorhabditis elegans Proteins / Q000235:genetics / Q000502:physiology; D057906:Circadian Clocks / Q000235:genetics* / Q000502:physiology*; D002940:Circadian Rhythm / Q000235:genetics / Q000502:physiology; D017124:Conserved Sequence; D019143:Evolution, Molecular; D054768:G-Protein-Coupled Receptor Kinases / Q000235:genetics / Q000502:physiology; D017238:Genes, Helminth; D005819:Genetic Markers; D008957:Models, Genetic; D008969:Molecular Sequence Data; D061105:Peroxiredoxin III / Q000235:genetics / Q000502:physiology; D054464:Peroxiredoxins / Q000235:genetics / Q000502:physiology; D018510:RNA, Helminth / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D012903:Smell / Q000235:genetics* / Q000502:physiology*; D013696:Temperature; D014157:Transcription Factors / Q000235:genetics / Q000502:physiology
chemical_list: D029742:Caenorhabditis elegans Proteins; D005819:Genetic Markers; C400538:LIN-42 protein, C elegans; D018510:RNA, Helminth; D012333:RNA, Messenger; D014157:Transcription Factors; C534226:PRDX-2 protein, C elegans; D061105:Peroxiredoxin III; D054464:Peroxiredoxins; D054768:G-Protein-Coupled Receptor Kinases; C572772:GRK-2 protein, C elegans