title: Localization of leucomyosuppressin in the brain and circadian clock of the cockroach Leucophaea maderae.
abstract: The myosuppressins (X1DVX2HX3FLRFamide), which reduce the frequency of insect muscle contractions, constitute a subgroup of the FMRFamide-related peptides. In the cockroach Leucophaea maderae, we have examined whether leucomyosuppressin (pQDVDHVFLRFamide) is present in the accessory medulla, viz., the circadian clock, which governs circadian locomotor activity rhythms. Antisera that specifically recognize leucomyosuppressin stain one to three neurons near the accessory medulla. MALDI-TOF mass spectrometry has confirmed the presence of leucomyosuppressin in the isolated accessory medulla. Injections of 1.15 pmol leucomyosuppressin into the vicinity of the accessory medulla at various circadian times have revealed no statistically significant effects on the phase of circadian locomotor activity rhythms. This is consistent with the morphology of the myosuppressin-immunoreactive neurons, which restrict their arborizations to the circadian clock and other optic lobe neuropils. Thus, leucomyosuppressin might play a role in the circadian system other than in the control of locomotor activity rhythms.
authors.affiliation: Department of Biology, Animal Physiology, Philipps University Marburg, Marburg, Germany.
authors.forename: Sandra
authors.initials: S
authors.lastname: Söhler
authors.forename: Susanne
authors.initials: S
authors.lastname: Neupert
authors.forename: Reinhard
authors.initials: R
authors.lastname: Predel
authors.forename: Ruthann
authors.initials: R
authors.lastname: Nichols
authors.forename: Monika
authors.initials: M
authors.lastname: Stengl
mesh_terms: D000818:Animals; D001683:Biological Clocks / Q000502:physiology*; D001921:Brain / Q000166:cytology / Q000378:metabolism*; D002940:Circadian Rhythm / Q000502:physiology*; D003058:Cockroaches / Q000378:metabolism*; D007150:Immunohistochemistry; D008297:Male; D008958:Models, Molecular; D009043:Motor Activity; D009479:Neuropeptides / Q000737:chemistry / Q000378:metabolism*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D009479:Neuropeptides; C058650:leucomyosuppressin