title: Identification of a prothoracicostatic peptide in the larval brain of the silkworm, Bombyx mori.
abstract: Prothoracicotropic hormone (PTTH) stimulates ecdysteroid biosynthesis in the prothoracic gland (PG) of insects. A peptide inhibiting ecdysteroid biosynthesis in the PG was isolated from the extracts of 2,000 larval brains of the silkworm, Bombyx mori, using a protocol that included four reversed-phase high performance liquid chromatography procedures. The primary structure of this prothoracicostatic peptide (Bom-PTSP) was determined to be H-Ala-Trp-Gln-Asp-Leu-Asn-Ser-Ala-Trp-NH(2). This neuropeptide has the same sequence as Mas-MIP-I, a myoinhibitory peptide previously isolated from the ventral nerve cord of the tobacco hornworm, Manduca sexta, and is highly homologous with the N-terminal portion of vertebrate peptides of the galanin family. This peptide inhibited PTTH-stimulated ecdysteroidogenesis in the PG at both the spinning and feeding stages, which indicates that Bom-PTSP interferes with PTTH-stimulated ecdysteroidogenesis.
authors.affiliation: Laboratory of Bioactive Substances, National Institute of Sericultural and Entomological Sciences, Ohwashi 1-2, Tsukuba, Ibaraki 305-8634, Japan.
authors.forename: Y J
authors.initials: YJ
authors.lastname: Hua
authors.forename: Y
authors.initials: Y
authors.lastname: Tanaka
authors.forename: K
authors.initials: K
authors.lastname: Nakamura
authors.forename: M
authors.initials: M
authors.lastname: Sakakibara
authors.forename: S
authors.initials: S
authors.lastname: Nagata
authors.forename: H
authors.initials: H
authors.lastname: Kataoka
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D012831:Bombyx / Q000737:chemistry*; D001923:Brain Chemistry; D004305:Dose-Response Relationship, Drug; D004347:Drug Interactions; D026461:Ecdysteroids; D019004:Galanin; D007301:Insect Hormones / Q000096:biosynthesis / Q000494:pharmacology; D007814:Larva / Q000737:chemistry; D008969:Molecular Sequence Data; D009479:Neuropeptides / Q000302:isolation & purification* / Q000494:pharmacology; D009842:Oligopeptides / Q000494:pharmacology; D020539:Sequence Analysis, Protein; D017386:Sequence Homology, Amino Acid; D013256:Steroids / Q000096:biosynthesis*
chemical_list: D026461:Ecdysteroids; D007301:Insect Hormones; D009479:Neuropeptides; D009842:Oligopeptides; D013256:Steroids; C400522:alanyl-tryptophyl-glutaminyl-aspartyl-leucyl-asparagyl-seryl-alanyl-tryptophanamide; C094891:prothoracicostatic hormone, Neobellieria bullata; D019004:Galanin