title: A novel adipokinetic octapeptide found in the damselflies Pseudagrion inconspicuum and Ischnura senegalensis.
abstract: A member of the adipokinetic hormone family of peptide was identified in the damselflies Pseudagrion inconspicuum and Ischnura senegalensis using a heterologous (in migratory locusts and American cockroaches) and a homologous (in P. inconspicuum) bioassay. After isolation of the peptide by reversed-phase h.p.i.c. of corpora cardiaca, its structure was determined by automated Edman degradation and matrix-assisted laser-desorption ionization m.s. The sequence of a blocked uncharged octapeptide was established: pGlu-Val-Asn-Phe-Thr-Pro-Gly-TrpNH2. One corpus cardiacum of P. inconspicuum contains about 2.4 pmol of this novel peptide. The synthetic peptide was chromatographically indistinguishable from the natural compound, and on injection in low quantities into the damselfly P. inconspicuum, haemolymph levels of lipids were increased. It is concluded that the novel peptide may be involved in controlling lipid mobilization during flight. Hence the peptide is designated Psi-AKH, Pseudagrion inconspicuum adipokinetic hormone.
authors.affiliation: Zoology Department, University of Cape Town, Rondebosch, South Africa.
authors.forename: M P
authors.initials: MP
authors.lastname: Janssens
authors.forename: R
authors.initials: R
authors.lastname: Kellner
authors.forename: G
authors.initials: G
authors.lastname: Gde
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001681:Biological Assay; D050260:Carbohydrate Metabolism; D002851:Chromatography, High Pressure Liquid; D003058:Cockroaches / Q000378:metabolism; D005260:Female; D006110:Grasshoppers / Q000378:metabolism; D006458:Hemolymph / Q000737:chemistry / Q000378:metabolism; D007301:Insect Hormones / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D007313:Insecta / Q000737:chemistry* / Q000378:metabolism; D050356:Lipid Metabolism; D008055:Lipids / Q000097:blood; D008297:Male; D013058:Mass Spectrometry; D008969:Molecular Sequence Data; D009490:Neurosecretory Systems / Q000737:chemistry*; D009842:Oligopeptides / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D011761:Pyrrolidonecarboxylic Acid / Q000031:analogs & derivatives
chemical_list: D007301:Insect Hormones; D008055:Lipids; D009842:Oligopeptides; C044833:adipokinetic hormone; D011761:Pyrrolidonecarboxylic Acid