title: Molecular characterization, tissue distribution, and ultrastructural localization of adipokinetic hormones in the CNS of the firebug Pyrrhocoris apterus (Heteroptera, Insecta).
abstract: Adipokinetic hormones (AKHs) are a group of insect metabolic neurohormones, synthesized and released from an endocrine retrocerebral gland, the corpus cardiacum (CC). Small amounts of AKH have also been identified in the brain, although their role in this organ is not clear. To address this gap in the knowledge about insect brain biology, we studied the nucleotide sequence, tissue distribution, and subcellular localization of AKHs in the brain and CC of the firebug Pyrrhocoris apterus. This insect expresses two AKHs; the octapeptides Pyrap-AKH and Peram-CAH-II, the presence of which was documented in the both studied organs. In situ hybridization and quantitative reverse-transcription (q-RT)-PCR revealed the expression of the genes encoding for both AKHs not only in the CC, but also in brain. Electron microscopy analysis of the brain revealed the presence of these hormones in specialized secretory granules localized predominantly in the cellular bodies of neurons. The hormones might be transported from the granules into the axons, where they could play a role in neuronal signaling. Under acute stress induced by the injection of 3μmol KCl, the level of AKHs in the brain increased to a greater extent than that in the CC. These results might indicate an enhanced role of brain-derived AKHs in defence reaction under acute stress situations.
authors.affiliation: Institute of Entomology, Biology Centre, Academy of Sciences, Branišovská 31, 370 05 České Budějovice, Czech Republic; Faculty of Science, University of South Bohemia, Branišovská 31, 370 05 České Budějovice, Czech Republic. Electronic address: kodrik@entu.cas.cz.
authors.forename: Dalibor
authors.initials: D
authors.lastname: Kodrík
authors.affiliation: Institute of Entomology, Biology Centre, Academy of Sciences, Branišovská 31, 370 05 České Budějovice, Czech Republic.
authors.forename: Tereza
authors.initials: T
authors.lastname: Stašková
authors.affiliation: Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Kamýcká 129, 165 21 Prague, Czech Republic.
authors.forename: Veronika
authors.initials: V
authors.lastname: Jedličková
authors.affiliation: Faculty of Science, University of South Bohemia, Branišovská 31, 370 05 České Budějovice, Czech Republic.
authors.forename: František
authors.initials: F
authors.lastname: Weyda
authors.affiliation: Institute of Entomology, Biology Centre, Academy of Sciences, Branišovská 31, 370 05 České Budějovice, Czech Republic; Faculty of Education, University of South Bohemia, Jeronýmova 10, 371 15 České Budějovice, Czech Republic.
authors.forename: Radka
authors.initials: R
authors.lastname: Závodská
authors.affiliation: Institute of Entomology, Biology Centre, Academy of Sciences, Branišovská 31, 370 05 České Budějovice, Czech Republic.
authors.forename: Jitka
authors.initials: J
authors.lastname: Pflegerová
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002490:Central Nervous System / Q000378:metabolism* / Q000648:ultrastructure*; D003001:Cloning, Molecular; D015870:Gene Expression; D020062:Heteroptera / Q000235:genetics / Q000378:metabolism / Q000648:ultrastructure; D007301:Insect Hormones / Q000235:genetics* / Q000378:metabolism*; D008969:Molecular Sequence Data; D009842:Oligopeptides / Q000235:genetics* / Q000378:metabolism*; D011761:Pyrrolidonecarboxylic Acid / Q000031:analogs & derivatives* / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D013312:Stress, Physiological / Q000235:genetics; D014018:Tissue Distribution
chemical_list: D007301:Insect Hormones; D009842:Oligopeptides; C044833:adipokinetic hormone; D011761:Pyrrolidonecarboxylic Acid
keywords: AKH; Electron microscopy; Immunoreaction; Insect brain; Pre-pro-hormone; Secretory granule