title: Myosuppressin is involved in the regulation of pupal diapause in the cabbage army moth Mamestra brassicae.
abstract: Diapause, a programmed developmental arrest, is common in insects, enabling them to survive adverse seasons. It is well established that pupal diapause is regulated by ecdysteroids secreted by the prothoracic glands (PGs), with cessation of ecdysteroid secretion after pupal ecdysis leading to pupal diapause. A major factor regulating the gland activity is prothoracicotropic hormone (PTTH) secreted from the brain. In our previous study, we demonstrated that the cessation of PTTH release after pupal ecdysis resulted in the inactivation of the PGs, leading to pupal diapause in the cabbage army moth Mamestra brassicae. Here we show that a neuropeptide myosuppressin also contributes to the inactivation of PGs at the initiation of diapause. Myosuppressin suppresses PTTH-stimulated activation of the PGs in vitro. Concentrations of myosuppressin in the hemolymph after pupal ecdysis are higher in diapause pupae than in nondiapause pupae.
authors.affiliation: Division of Biological Science, Graduate School of Science, Nagoya University, Nagoya, Japan.
authors.forename: Nobuto
authors.initials: N
authors.lastname: Yamada
authors.affiliation: Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Chiba, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kataoka
authors.affiliation: Division of Biological Science, Graduate School of Science, Nagoya University, Nagoya, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Mizoguchi
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001921:Brain / Q000502:physiology; D001937:Brassica / Q000469:parasitology; D002490:Central Nervous System / Q000502:physiology; D000074767:Diapause; D015870:Gene Expression; D006458:Hemolymph; D007301:Insect Hormones / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D009036:Moths / Q000502:physiology*; D011679:Pupa
chemical_list: D007301:Insect Hormones; C009089:prothoracicotropic hormone