title: A novel adipokinetic peptide in a water boatman (Heteroptera, Corixidae) and its bioanalogue in a saucer bug (Heteroptera, Naucoridae).
abstract: The corpora cardiaca (CC) of two water bug species, the water boatman Corixa punctata and the saucer bug Ilyocoris cimicoides, contain a substance that cause hyperlipemia in the migratory locust. The primary sequence of one octapeptide belonging to the adipokinetic hormone (AKH)/red pigment-concentrating hormone (RPCH) family was deduced from the multiple MS(N) electrospray mass data of CC material from each species. Whereas the saucer bug contains the known octapeptide pGlu-Val-Asn-Phe-Ser-Pro-Ser-Trp amide, code-named Anaim-AKH, the water boatman has a novel peptide identified as pGlu-Leu/Ile-Asn-Phe-Ser-Pro-Ser-Trp amide, code-named Corpu-AKH. The ambiguity about the amino acid at position 2, i.e. Leu or Ile, in Corpu-AKH was solved by isolating the peptide in a single-step by reversed-phase HPLC and establishing co-elution with the synthetic peptide containing Leu at position 2. Functionally, the peptides regulate lipid mobilization, as evidenced by an adipokinetic effect after injecting synthetic Anaim-AKH and Corpu-AKH into the respective acceptor species. Swimming activity of I. cimicoides also causes hyperlipemia.
authors.affiliation: Zoology Department, University of Cape Town, Private Bag, ZA-7701 Rondebosch, South Africa. Gerd.Gade@uct.ac.za
authors.forename: Gerd
authors.initials: G
authors.lastname: Gäde
authors.forename: Petr
authors.initials: P
authors.lastname: Simek
authors.forename: Heather G
authors.initials: HG
authors.lastname: Marco
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002853:Chromatography, Liquid; D005260:Female; D020062:Heteroptera / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D007301:Insect Hormones / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D050356:Lipid Metabolism; D008297:Male; D009479:Neuropeptides / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D009842:Oligopeptides / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D010802:Phylogeny; D011761:Pyrrolidonecarboxylic Acid / Q000031:analogs & derivatives* / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D013045:Species Specificity; D013050:Spectrometry, Fluorescence; D021241:Spectrometry, Mass, Electrospray Ionization
chemical_list: D007301:Insect Hormones; D009479:Neuropeptides; D009842:Oligopeptides; C044833:adipokinetic hormone; D011761:Pyrrolidonecarboxylic Acid