title: An ion channel of the degenerin/epithelial sodium channel superfamily controls the defecation rhythm in Caenorhabditis elegans.
abstract: Ultradian rhythms are widespread phenomena found in various biological organisms. A typical example is the defecation behavior of the nematode Caenorhabditis elegans, which repeats at about 45-sec intervals. To elucidate the mechanism, we studied flr-1 mutants, which show very short defecation cycle periods. The mutations also affect some food-related functions, including growth rate, the expulsion step of defecation behavior, and the regulation of the dauer larva (a nonfeeding, special third-stage larva) formation in the unc-3 (Olf-1/EBF homolog) background. The flr-1 gene encodes a novel ion channel belonging to the DEG/ENaC (C. elegans degenerin and mammalian epithelial sodium channel) superfamily. A flr-1::GFP (green fluorescent protein) fusion gene that can rescue the flr-1 mutant phenotypes is expressed only in the intestine from embryos to adults. These results suggest that FLR-1 may be a component of an intestinal regulatory system that controls the defecation rhythm as well as other functions.
authors.affiliation: Structural Biology Center, National Institute of Genetics, Mishima 411-8540, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Take-Uchi
authors.forename: M
authors.initials: M
authors.lastname: Kawakami
authors.forename: T
authors.initials: T
authors.lastname: Ishihara
authors.forename: T
authors.initials: T
authors.lastname: Amano
authors.forename: K
authors.initials: K
authors.lastname: Kondo
authors.forename: I
authors.initials: I
authors.lastname: Katsura
mesh_terms: D000204:Activity Cycles / Q000235:genetics; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D017173:Caenorhabditis elegans / Q000235:genetics / Q000254:growth & development / Q000502:physiology*; D003001:Cloning, Molecular; D017931:DNA Primers / Q000235:genetics; D003672:Defecation / Q000187:drug effects / Q000235:genetics / Q000502:physiology*; D005459:Fluorides / Q000494:pharmacology; D017238:Genes, Helminth; D017930:Genes, Reporter; D049452:Green Fluorescent Proteins; D007422:Intestines / Q000196:embryology / Q000254:growth & development / Q000502:physiology; D007473:Ion Channels / Q000187:drug effects / Q000235:genetics / Q000502:physiology*; D008164:Luminescent Proteins / Q000235:genetics; D008969:Molecular Sequence Data; D009154:Mutation; D010641:Phenotype; D016133:Polymerase Chain Reaction; D017386:Sequence Homology, Amino Acid; D015222:Sodium Channels / Q000187:drug effects / Q000235:genetics / Q000502:physiology*
chemical_list: D017931:DNA Primers; D007473:Ion Channels; D008164:Luminescent Proteins; D015222:Sodium Channels; D049452:Green Fluorescent Proteins; D005459:Fluorides