title: Characterization and pharmacological analysis of two adipokinetic hormone receptor variants of the tsetse fly, Glossina morsitans morsitans.
abstract: Adipokinetic hormones (AKH) are well known regulators of energy metabolism in insects. These neuropeptides are produced in the corpora cardiaca and perform their hormonal function by interacting with specific G protein-coupled receptors (GPCRs) at the cell membranes of target tissues, mainly the fat body. Here, we investigated the sequences, spatial and temporal distributions, and pharmacology of AKH neuropeptides and receptors in the tsetse fly, Glossina morsitans morsitans. The open reading frames of two splice variants of the Glomo-akh receptor (Glomo-akhr) gene and of the AKH neuropeptide encoding genes, gmmhrth and gmmakh, were cloned. Both tsetse AKHR isoforms show strong sequence conservation when compared to other insect AKHRs. Glomo-AKH prepropeptides also have the typical architecture of AKH precursors. In an in vitro Ca(2+) mobilization assay, Glomo-AKH neuropeptides activated each receptor isoform up to nanomolar concentrations. We identified structural features of tsetse AKH neuropeptides essential for receptor activation in vitro. Gene expression profiles suggest a function for AKH signaling in regulating Glossina energy metabolism, where AKH peptides are released from the corpora cardiaca and activate receptors mainly expressed in the fat body. This analysis of the ligand-receptor coupling, expression, and pharmacology of the two Glomo-AKHR variants facilitates further elucidation of the function of AKH in G. m. morsitans.
authors.affiliation: Functional Genomics and Proteomics, Department of Biology, KU Leuven, Naamsestraat 59, 3000, Leuven, Belgium. Electronic address: Jelle.Caers@bio.kuleuven.be.
authors.forename: Jelle
authors.initials: J
authors.lastname: Caers
authors.affiliation: Functional Genomics and Proteomics, Department of Biology, KU Leuven, Naamsestraat 59, 3000, Leuven, Belgium. Electronic address: Tom.Janssen@cistim.be.
authors.forename: Tom
authors.initials: T
authors.lastname: Janssen
authors.affiliation: Functional Genomics and Proteomics, Department of Biology, KU Leuven, Naamsestraat 59, 3000, Leuven, Belgium. Electronic address: Liesbeth.VanRompay@bio.kuleuven.be.
authors.forename: Liesbeth
authors.initials: L
authors.lastname: Van Rompay
authors.affiliation: Functional Genomics and Proteomics, Department of Biology, KU Leuven, Naamsestraat 59, 3000, Leuven, Belgium. Electronic address: Valerie.Broeckx@bio.kuleuven.be.
authors.forename: Valérie
authors.initials: V
authors.lastname: Broeckx
authors.affiliation: Unit of Veterinary Protozoology, Department of Biomedical Sciences, Institute of Tropical Medicine, Nationalestraat 155, 2000, Antwerpen, Belgium; Laboratory of Zoophysiology, Department of Physiology, University of Ghent, Krijgslaan 281, 9000, Ghent, Belgium. Electronic address: jvdabbeele@itg.be.
authors.forename: Jan
authors.initials: J
authors.lastname: Van Den Abbeele
authors.affiliation: Department of Biological Sciences, University of Cape Town, Private Bag, 7701, Rondebosch, South Africa. Electronic address: gerd.gade@uct.ac.za.
authors.forename: Gerd
authors.initials: G
authors.lastname: Gäde
authors.affiliation: Functional Genomics and Proteomics, Department of Biology, KU Leuven, Naamsestraat 59, 3000, Leuven, Belgium. Electronic address: Liliane.Schoofs@bio.kuleuven.be.
authors.forename: Liliane
authors.initials: L
authors.lastname: Schoofs
authors.affiliation: Functional Genomics and Proteomics, Department of Biology, KU Leuven, Naamsestraat 59, 3000, Leuven, Belgium. Electronic address: Isabel.Beets@bio.kuleuven.be.
authors.forename: Isabel
authors.initials: I
authors.lastname: Beets
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D016466:CHO Cells; D003412:Cricetulus; D005260:Female; D020869:Gene Expression Profiling; D007301:Insect Hormones / Q000737:chemistry / Q000378:metabolism*; D008969:Molecular Sequence Data; D009842:Oligopeptides / Q000737:chemistry / Q000378:metabolism*; D011761:Pyrrolidonecarboxylic Acid / Q000031:analogs & derivatives* / Q000737:chemistry / Q000378:metabolism; D043562:Receptors, G-Protein-Coupled / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D014370:Tsetse Flies / Q000378:metabolism*
chemical_list: D007301:Insect Hormones; D009842:Oligopeptides; D043562:Receptors, G-Protein-Coupled; C044833:adipokinetic hormone; D011761:Pyrrolidonecarboxylic Acid
keywords: Adipokinetic hormone; G protein-coupled receptor; Insect; Neuropeptide; Tsetse fly