The first decapeptide adipokinetic hormone (AKH) in Heteroptera: a novel AKH from a South African saucer bug, Laccocoris spurcus (Naucoridae, Laccocorinae).
A novel peptide of the adipokinetic hormone (AKH)/red pigment-concentrating hormone (RPCH) family has been elucidated by mass spectrometry from the corpora cardiaca of an African saucer bug species, Laccocoris spurcus. It is the first decapeptide member found in the species-rich taxon Heteroptera, has the primary sequence pGlu-Val-Asn-Phe-Ser-Pro-Ser-Trp-Gly-Gly amide and is denoted as Lacsp-AKH. The first eight amino acids are identical to the octapeptide Anaim-AKH of the European saucer bug, Ilyocoris cimicoides. The synthetic peptide Lacsp-AKH elevates lipids upon injection into the hemolymph of L. spurcus at a low dose of 3 pmol. Swimming activity in this saucer bug also causes a significant increase in the lipid concentration in the hemolymph. Thus, both results point to an apparent function of the endogenous new decapeptide Lacsp-AKH in L. spurcus, namely, to regulate lipid mobilization. Isolation of an AKH peptide from the corpora cardiaca of the water bug Aphelocheirus aestivalis (Aphelocheiridae) resulted in the assignment of the octapeptide Anaim-AKH, supporting current phylogenies on the infraorder Nepomorpha.
Marco
Heather G
HG
Zoology Department, University of Cape Town, Private Bag, ZA-7701, Rondebosch, South Africa.
Simek
Petr
P
Gäde
Gerd
G
D000818:Animals; D006458:Hemolymph / Q000187:drug effects; D020062:Heteroptera / Q000187:drug effects* / Q000378:metabolism*; D007301:Insect Hormones / Q000737:chemistry*; D013058:Mass Spectrometry; D009842:Oligopeptides / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D011761:Pyrrolidonecarboxylic Acid / Q000031:analogs & derivatives* / Q000737:chemistry
D007301:Insect Hormones; D009842:Oligopeptides; C044833:adipokinetic hormone; D011761:Pyrrolidonecarboxylic Acid