title: Phase shifts of the circadian locomotor rhythm induced by pigment-dispersing factor in the cricket Gryllus bimaculatus.
abstract: Pigment-dispersing factors (PDFs) are octadeca-peptides widely distributed in insect optic lobes and brain. In this study, we have purified PDF and determined its amino acid sequence in the cricket Gryllus bimaculatus. Its primary structure was NSEIINSLLGLPKVLNDA-NH(2), homologous to other PDH family members so far reported. When injected into the optic lobe of experimentally blinded adult male crickets, Gryllus-PDF induced phase shifts in their activity rhythms in a phase dependent and dose dependent manner. The resulted phase response curve (PRC) showed delays during the late subjective night to early subjective day and advances during the mid subjective day to mid subjective night. The PRC was different in shape from those for light, serotonin and temperature. These results suggest that PDF plays a role in phase regulation of the circadian clock through a separate pathway from those of other known phase regulating agents.
authors: Department of Physics, Biology and Informatics, Faculty of Science, Research Institute of Time Studies, Yamaguchi University, Yamaguchi, Japan.
authors: Muniyandi
authors: M
authors: Singaravel
authors: Yuko
authors: Y
authors: Fujisawa
authors: Miki
authors: M
authors: Hisada
authors: A S M
authors: AS
authors: Saifullah
authors: Kenji
authors: K
authors: Tomioka
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002940:Circadian Rhythm / Q000187:drug effects / Q000502:physiology*; D029721:Drosophila Proteins; D004797:Enzyme-Linked Immunosorbent Assay; D006135:Gryllidae / Q000235:genetics / Q000502:physiology*; D008969:Molecular Sequence Data; D009479:Neuropeptides / Q000235:genetics* / Q000494:pharmacology; D017422:Sequence Analysis, DNA
chemical_list: D029721:Drosophila Proteins; D009479:Neuropeptides; C113883:pdf protein, Drosophila