title: Novel members of the adipokinetic hormone family in beetles of the superfamily Scarabaeoidea.
abstract: Eight beetle species of the superfamily Scarabaeoidea were investigated with respect to peptides belonging to the adipokinetic hormone (AKH) family in their neurohemal organs, the corpora cardiaca (CC). The following beetle families are represented: Scarabaeidae, Lucanidae, and Geotrupidae. AKH peptides were identified through a heterospecific trehalose-mobilizing bioassay and by sequence analyses, using liquid chromatography coupled to positive electrospray mass spectrometry (LC-ESI-MS) and analysis of the tandem MS2spectra obtained by collision-induced dissociation. All the beetle species have octapeptide AKHs; some have two AKHs, while others have only one. Novel AKH members were found in Euoniticellus intermedius and Circellium bacchus (family Scarabaeidae), as well as in Dorcus parallelipipedus (family Lucanidae). Two species of the family Geotrupidae and two species of the Scarabaeidae subfamily Cetoniinae contain one known AKH peptide, Melme-CC, while E. intermedius produces a novel peptide code named Euoin-AKH: pEINFTTGWamide. Two AKH peptides were each identified in CC of C. bacchus and D. parallelipipedus: the novel Cirba-AKH: pEFNFSAGWamide and the known peptide, Scade-CC-I in the former, and the novel Dorpa-AKH: pEVNYSPVW amide and the known peptide, Melme-CC in the latter. Kheper bonelli (subfamily Scarabaeinae) also has two AKHs, the known Scade-CC-I and Scade-CC-II. All the novel peptides were synthesized and the amino acid sequence assignments were unequivocally confirmed by co-elution of the synthetic peptides with their natural equivalent, and identical MS parameters of the two forms. The novel synthetic peptides are all active in inducing hypertrehalosemia in cockroaches.
authors.affiliation: Department of Biological Sciences, University of Cape Town, Private Bag, Rondebosch, 7700, South Africa. gerd.gade@uct.ac.za.
authors.forename: Gerd
authors.initials: G
authors.lastname: Gäde
authors.affiliation: Biology Centre, Czech Academy of Sciences, 37005, Ceske Budejovice, Czech Republic.
authors.forename: Petr
authors.initials: P
authors.lastname: Šimek
authors.affiliation: Department of Biological Sciences, University of Cape Town, Private Bag, Rondebosch, 7700, South Africa.
authors.forename: Heather G
authors.initials: HG
authors.lastname: Marco
mesh_terms: D000595:Amino Acid Sequence / Q000235:genetics; D000818:Animals; D002853:Chromatography, Liquid; D001517:Coleoptera / Q000737:chemistry* / Q000235:genetics; D007301:Insect Hormones / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification; D013058:Mass Spectrometry; D009842:Oligopeptides / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification; D010455:Peptides / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification; D011761:Pyrrolidonecarboxylic Acid / Q000031:analogs & derivatives* / Q000737:chemistry / Q000302:isolation & purification
chemical_list: D007301:Insect Hormones; D009842:Oligopeptides; D010455:Peptides; C044833:adipokinetic hormone; D011761:Pyrrolidonecarboxylic Acid
keywords: Adipokinetic hormone family; Beetles; Geotrupidae; Insects; Liquid chromatography; Lucanidae; Mass spectrometry; Scarabaeidae