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Audsley N, Matthews HJ, Down RE, Weaver RJ. Neuropeptides associated with the central nervous system of the cabbage root fly, Delia radicum (L). Peptides 2011; 32:434-40. [PMID: 20869420 DOI: 10.1016/j.peptides.2010.08.028] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/20/2010] [Revised: 08/16/2010] [Accepted: 08/16/2010] [Indexed: 11/23/2022]
Abstract
The peptidome of the central nervous system of adult cabbage root fly, Delia radicum (L) was investigated using matrix assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF MS). Over twenty neuropeptides were identified from three different tissue sources, the combined brain/suboesophageal ganglion (SOG), the retrocerebral complex, and the thoracic-abdominal ganglion (TAG). A number of peptides were identified in all three tissues, including allatostatins, short neuropeptide F-like peptides, corazonin, a pyrokinin, and a myosuppressin. Adipokinetic hormone was restricted to the retrocerebral complex. Other peptides, including FMRFamides and sulfakinins were detected only in the brain/SOG and TAG. Some peptides, notably myoinhibitory peptides and tachykinins, which have been identified in other fly species, were not detected in any tissue sample. This study has structurally characterized for the first time, the neuropeptides from adult D. radicum.
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Affiliation(s)
- Neil Audsley
- The Food and Environment Research Agency, Sand Hutton, York, YO41 1LZ, UK.
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52
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Lindemans M, Janssen T, Beets I, Temmerman L, Meelkop E, Schoofs L. Gonadotropin-releasing hormone and adipokinetic hormone signaling systems share a common evolutionary origin. Front Endocrinol (Lausanne) 2011; 2:16. [PMID: 22649364 PMCID: PMC3356000 DOI: 10.3389/fendo.2011.00016] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2011] [Accepted: 06/16/2011] [Indexed: 11/13/2022] Open
Abstract
Gonadotropin-releasing hormone (GnRH) is a critical and central hormone that regulates vertebrate reproduction. The high conservation of GnRH signaling within the chordates (deuterostomians) raises the important question as to whether its appearance might date back prior to the divergence of protostomian and deuterostomian lineages, about 700 million years ago. This leads to several important questions regarding the evolution of the GnRH family. Has GnRH been retained in most protostomian lineages? And was regulation of reproduction already a function of ancestral GnRH? The first question can undoubtedly be answered affirmatively since several GnRH-like sequences have been found in wide variety of protostomian and deuterostomian phyla. However, based on their different primary functions in different phyla - which implies a less unanimous answer on the second question - consistency in the nomenclature of this peptide family has been lost. A comparative and phylogenetic approach shows that the ecdysozoan adipokinetic hormones (AKHs), lophotrochozoan GnRHs and chordate GnRHs are structurally related and suggests that they all originate from a common ancestor. This review supports the view that the AKH-GnRH signaling system probably arose very early in metazoan evolution, prior to the divergence of protostomians and deuterostomians.
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Affiliation(s)
- Marleen Lindemans
- Functional Genomics and Proteomics Research Unit, Katholieke Universiteit LeuvenLeuven, Belgium
| | - Tom Janssen
- Functional Genomics and Proteomics Research Unit, Katholieke Universiteit LeuvenLeuven, Belgium
| | - Isabel Beets
- Functional Genomics and Proteomics Research Unit, Katholieke Universiteit LeuvenLeuven, Belgium
| | - Liesbet Temmerman
- Functional Genomics and Proteomics Research Unit, Katholieke Universiteit LeuvenLeuven, Belgium
| | - Ellen Meelkop
- Functional Genomics and Proteomics Research Unit, Katholieke Universiteit LeuvenLeuven, Belgium
| | - Liliane Schoofs
- Functional Genomics and Proteomics Research Unit, Katholieke Universiteit LeuvenLeuven, Belgium
- *Correspondence: Liliane Schoofs, Functional Genomics and Proteomics Research Unit, Zoological Institute, Katholieke Universiteit Leuven, Naamsestraat 59, B-3000 Leuven, Belgium. e-mail:
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Ziegler R, Isoe J, Moore W, Riehle MA, Wells MA. The putative AKH receptor of the tobacco hornworm, Manduca sexta, and its expression. JOURNAL OF INSECT SCIENCE (ONLINE) 2011; 11:40. [PMID: 21529255 PMCID: PMC3281483 DOI: 10.1673/031.011.0140] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/23/2010] [Accepted: 08/10/2010] [Indexed: 05/30/2023]
Abstract
Adipokinetic hormones are peptide hormones that mobilize lipids and/or carbohydrates for flight in adult insects and activate glycogen Phosphorylase in larvae during starvation and during molt. We previously examined the functional roles of adipokinetic hormone in Manduca sexta L. (Lepidoptera: Sphingidae). Here we report the cloning of the full-length cDNA encoding the putative adipokinetic hormone receptor from the fat body of M. sexta. The sequence analysis shows that the deduced amino acid sequence shares common motifs of G protein-coupled receptors, by having seven hydrophobic transmembrane segments. We examined the mRNA expression pattern of the adipokinetic hormone receptor by quantitative Real-Time PCR in fat body during development and in different tissues and found the strongest expression in fat body of larvae two days after molt to the fifth instar. We discuss these results in relation to some of our earlier results. We also compare the M. sexta adipokinetic hormone receptor with the known adipokinetic hormone receptors of other insects and with gonadotropin releasing hormone-like receptors of invertebrates.
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Affiliation(s)
- R. Ziegler
- Department of Entomology, The University of Arizona, Tucson, AZ 85721 USA
| | - J. Isoe
- Department of Chemistry and Biochemistry, The University of Arizona, Tucson, AZ 85721 USA
| | - W. Moore
- Department of Entomology, The University of Arizona, Tucson, AZ 85721 USA
| | - M. A. Riehle
- Department of Entomology, The University of Arizona, Tucson, AZ 85721 USA
| | - M. A. Wells
- Department of Chemistry and Biochemistry, The University of Arizona, Tucson, AZ 85721 USA
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Predel R, Neupert S, Garczynski SF, Crim JW, Brown MR, Russell WK, Kahnt J, Russell DH, Nachman RJ. Neuropeptidomics of the mosquito Aedes aegypti. J Proteome Res 2010; 9:2006-15. [PMID: 20163154 DOI: 10.1021/pr901187p] [Citation(s) in RCA: 107] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Neuropeptidomic data were collected on the mosquito Ae. aegypti, which is considered the most tractable mosquito species for physiological and endocrine studies. The data were solely obtained by direct mass spectrometric profiling, including tandem fragmentation, of selected tissues from single specimens, which yielded a largely complete accounting of the putative bioactive neuropeptides; truncated neuropeptides with low abundance were not counted as mature peptides. Differential processing within the CNS was detected for the CAPA-precursor, and differential post-translational processing (pyroglutamate formation) was detected for AST-C and CAPA-PVK-2. For the first time in insects, we succeeded in the direct mass spectrometric profiling of midgut tissue which yielded a comprehensive and immediate overview of the peptides involved in the endocrine system of the gut. Head peptides which were earlier identified as the most abundant RFamides of Ae. aegypti, were not detected in any part of the CNS or midgut. This study provides a framework for future investigations on mosquito endocrinology and neurobiology. Given the high sequence similarity of neuropeptide precursors identified in other medically important mosquitoes, conclusions regarding the peptidome of Ae. aegypti likely are applicable to these mosquitoes.
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Affiliation(s)
- Reinhard Predel
- Institute of General Zoology, Friedrich-Schiller-University, Erbertstrasse 1, Jena, Germany.
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55
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Rhea JM, Wegener C, Bender M. The proprotein convertase encoded by amontillado (amon) is required in Drosophila corpora cardiaca endocrine cells producing the glucose regulatory hormone AKH. PLoS Genet 2010; 6:e1000967. [PMID: 20523747 PMCID: PMC2877730 DOI: 10.1371/journal.pgen.1000967] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2009] [Accepted: 04/21/2010] [Indexed: 12/01/2022] Open
Abstract
Peptide hormones are potent signaling molecules that coordinate animal physiology, behavior, and development. A key step in activation of these peptide signals is their proteolytic processing from propeptide precursors by a family of proteases, the subtilisin-like proprotein convertases (PCs). Here, we report the functional dissection of amontillado (amon), which encodes the Drosophila homolog of the mammalian PC2 protein, using cell-type specific inactivation and rescue experiments, and we show that amon is required in the islet-like adipokinetic hormone (AKH)–producing cells that regulate sugar homeostasis. In Drosophila, AKH acts analogously to vertebrate glucagon to increase circulating sugar levels from energy stores, while insulin-like peptides (DILPs) act to decrease sugar levels. amon mutant larvae have significantly reduced hemolymph sugar levels, and thus phenocopy larvae where the AKH–producing cells in the corpora cardiaca have been ablated. Reduction of amon expression in these cells via cell-specific RNA inactivation also results in larvae with reduced sugar levels while expression of amon in AKH cells in an amon mutant background rescues hypoglycemia. Hypoglycemia in larvae resulting from amon RNA inactivation in the AKH cells can be rescued by global expression of the akh gene. Finally, mass spectrometric profiling shows that the production of mature AKH is inhibited in amon mutants. Our data indicate that amon function in the AKH cells is necessary to maintain normal sugar homeostasis, that amon functions upstream of akh, and that loss of mature AKH is correlated with loss of amon activity. These observations indicate that the AKH propeptide is a proteolytic target of the amon proprotein convertase and provide evidence for a conserved role of PC2 in processing metabolic peptide hormones. Peptide hormones are important signaling molecules that coordinate physiology, behavior, and development. A key step in production of peptide hormones is the proteolytic cleavage of larger inactive precursors by prohormone convertases (PCs). Studies in a variety of organisms, including humans, have shown that deficiencies in PC genes lead to complex and detrimental changes. We used fruitfly genetics to dissect the function of Drosophila PC2, encoded by the amon gene, in the regulation of carbohydrate metabolism. We found that amon is expressed in endocrine cells of the corpora cardiaca that produce the sugar-mobilizing adipokinetic hormone (AKH), a functional analog of vertebrate glucagon. Previous studies suggest that the AKH–producing cells are homologs of the glucagon-producing islet alpha-cells in the pancreas. We found that flies with amon deficiency had significantly reduced hemolymph (insect “blood”) sugar levels. Using cell-type specific inactivation and rescue experiments, we show that amon expression in the AKH cells is necessary and sufficient for normal sugar regulation. We also demonstrate that AKH production is inhibited in amon mutants. Our results indicate that amon is necessary to maintain normal hemolymph sugar levels by activating AKH and suggest a conservation of PC2 function in processing peptide hormones between flies and mammals.
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Affiliation(s)
- Jeanne M. Rhea
- Department of Genetics, University of Georgia, Athens, Georgia, United States of America
| | - Christian Wegener
- Emmy Noether Neuropeptide Group, Department of Animal Physiology, Philipps University, Marburg, Germany
| | - Michael Bender
- Department of Genetics, University of Georgia, Athens, Georgia, United States of America
- * E-mail:
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Hansen KK, Stafflinger E, Schneider M, Hauser F, Cazzamali G, Williamson M, Kollmann M, Schachtner J, Grimmelikhuijzen CJP. Discovery of a novel insect neuropeptide signaling system closely related to the insect adipokinetic hormone and corazonin hormonal systems. J Biol Chem 2010; 285:10736-47. [PMID: 20068045 PMCID: PMC2856281 DOI: 10.1074/jbc.m109.045369] [Citation(s) in RCA: 123] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2009] [Revised: 12/04/2009] [Indexed: 11/06/2022] Open
Abstract
Neuropeptides and their G protein-coupled receptors (GPCRs) play a central role in the physiology of insects. One large family of insect neuropeptides are the adipokinetic hormones (AKHs), which mobilize lipids and carbohydrates from the insect fat body. Other peptides are the corazonins that are structurally related to the AKHs but represent a different neuropeptide signaling system. We have previously cloned an orphan GPCR from the malaria mosquito Anopheles gambiae that was structurally intermediate between the A. gambiae AKH and corazonin GPCRs. Using functional expression of the receptor in cells in cell culture, we have now identified the ligand for this orphan receptor as being pQVTFSRDWNAamide, a neuropeptide that is structurally intermediate between AKH and corazonin and that we therefore named ACP (AKH/corazonin-related peptide). ACP does not activate the A. gambiae AKH and corazonin receptors and, vice versa, AKH and corazonin do not activate the ACP receptor, showing that the ACP/receptor couple is an independent and so far unknown peptidergic signaling system. Because ACP is structurally intermediate between AKH and corazonin and the ACP receptor between the AKH and corazonin receptors, this is a prominent example of receptor/ligand co-evolution, probably originating from receptor and ligand gene duplications followed by mutations and evolutionary selection, thereby yielding three independent hormonal systems. The ACP signaling system occurs in the mosquitoes A. gambiae, Aedes aegypti, and Culex pipiens (Diptera), the silkworm Bombyx mori (Lepidoptera), the red flour beetle Tribolium castaneum (Coleoptera), the parasitic wasp Nasonia vitripennis (Hymenoptera), and the bug Rhodnius prolixus (Hemiptera). However, the ACP system is not present in 12 Drosophila species (Diptera), the honeybee Apis mellifera (Hymenoptera), the pea aphid Acyrthosiphon pisum (Hemiptera), the body louse Pediculus humanus (Phthiraptera), and the crustacean Daphnia pulex, indicating that it has been lost several times during arthropod evolution. In particular, this frequent loss of hormonal systems is unique for arthropods compared with vertebrates.
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Affiliation(s)
- Karina K. Hansen
- From the Center for Functional and Comparative Insect Genomics, Department of Biology, University of Copenhagen, DK-2100 Copenhagen, Denmark and
| | - Elisabeth Stafflinger
- From the Center for Functional and Comparative Insect Genomics, Department of Biology, University of Copenhagen, DK-2100 Copenhagen, Denmark and
| | - Martina Schneider
- From the Center for Functional and Comparative Insect Genomics, Department of Biology, University of Copenhagen, DK-2100 Copenhagen, Denmark and
| | - Frank Hauser
- From the Center for Functional and Comparative Insect Genomics, Department of Biology, University of Copenhagen, DK-2100 Copenhagen, Denmark and
| | - Giuseppe Cazzamali
- From the Center for Functional and Comparative Insect Genomics, Department of Biology, University of Copenhagen, DK-2100 Copenhagen, Denmark and
| | - Michael Williamson
- From the Center for Functional and Comparative Insect Genomics, Department of Biology, University of Copenhagen, DK-2100 Copenhagen, Denmark and
| | - Martin Kollmann
- the Department of Animal Physiology, University of Marburg, D-35032 Marburg, Germany
| | - Joachim Schachtner
- the Department of Animal Physiology, University of Marburg, D-35032 Marburg, Germany
| | - Cornelis J. P. Grimmelikhuijzen
- From the Center for Functional and Comparative Insect Genomics, Department of Biology, University of Copenhagen, DK-2100 Copenhagen, Denmark and
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57
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Nuss AB, Forschler BT, Crim JW, TeBrugge V, Pohl J, Brown MR. Molecular characterization of neuropeptide F from the eastern subterranean termite Reticulitermes flavipes (Kollar) (Isoptera: Rhinotermitidae). Peptides 2010; 31:419-28. [PMID: 19747517 DOI: 10.1016/j.peptides.2009.09.001] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/15/2009] [Revised: 09/01/2009] [Accepted: 09/01/2009] [Indexed: 11/22/2022]
Abstract
Neuropeptide F (NPF)-like immunoreactivity was previously found to be abundant in the eastern subterranean termite, Reticulitermes flavipes. Purification of the NPF from a whole body extract of worker termites was accomplished in the current study by HPLC and heterologous radioimmunoassay for an NPF-related peptide, Helicoverpa zea Midgut Peptide-I. A partial amino acid sequence allowed determination of the corresponding cDNA that encoded an open reading frame deduced for authentic R. flavipes NPF (Ref NPF): KPSDPEQLADTLKYLEELDRFYSQVARPRFa. Effects of synthetic NPFs on muscle contractions were investigated for isolated foreguts and hindguts of workers, with Drm NPF inhibiting spontaneous contractions of hindguts. Phylogenetic analysis of invertebrate NPF sequences reveals two separate groupings, with Ref NPF occurring within a clade composed exclusively of arthropods.
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Affiliation(s)
- Andrew B Nuss
- Department of Entomology, 413 Biological Sciences Building, University of Georgia, Athens, GA 30602-2603, USA.
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58
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Neuropeptide Receptors as Possible Targets for Development of Insect Pest Control Agents. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2010; 692:211-26. [DOI: 10.1007/978-1-4419-6902-6_11] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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59
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Kaufmann C, Merzendorfer H, Gäde G. The adipokinetic hormone system in Culicinae (Diptera: Culicidae): molecular identification and characterization of two adipokinetic hormone (AKH) precursors from Aedes aegypti and Culex pipiens and two putative AKH receptor variants from A. aegypti. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2009; 39:770-781. [PMID: 19748585 DOI: 10.1016/j.ibmb.2009.09.002] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2009] [Revised: 09/02/2009] [Accepted: 09/04/2009] [Indexed: 05/28/2023]
Abstract
Insect neuropeptides of the adipokinetic hormone (AKH) family induce the mobilization of energy stores to fuel flight, but also affect the nutritional balance during diapause and oogenesis. They are therefore important regulators for flight, hibernation, and reproduction in mosquitoes including those that transmit human pathogens. In this study, we identified and analyzed the genes encoding two AKH preprohormones in the Yellow fever mosquito, Aedes aegypti: Aedae-AKH-I encodes the octapeptide pELFTPSWa and Aedae-AKH-II the decapeptide pEVTFSRDWNAa. Identical AKHs were identified in the West Nile virus vector, Culex pipiens, whose genes were characterized in this study as Culpi-AKH-I and Culpi-AKH-II. Using Northern blot, transcript expression was shown in A. aegypti, for Aedae-AKH-I in the head/thorax tissues of pupae and females, as well as in the abdomen of adult males; Aedae-AKH-II was only expressed in adults. In an immunocytological study using an AKH-antibody, the corpus cardiacum (CC), the intrinsic CC-cells (X-cells), the nervi corporis cardiaci, cells in the brain and thoracic ganglia were stained. In addition, two splice variants of the AKH-receptor gene were characterized in A. aegypti, (Aedae-AKHR-I and -II). RT-PCR revealed that both variants of these typical G-protein-coupled receptors were expressed in all life stages. Aedae-AKHR-I expression was also detected in the ovaries, indicating once more the influence of the AKH/AKHR system during the insect's oogenesis. Based on phylogenetic data, we postulate two closely related types of AKH-receptors that could bind selectively the two AKH peptides found in A. aegypti.
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Affiliation(s)
- Christian Kaufmann
- Department of Biology/Chemistry, University of Osnabrück, 49069 Osnabrück, Germany.
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60
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Lorenz MW, Gäde G. Hormonal regulation of energy metabolism in insects as a driving force for performance. Integr Comp Biol 2009; 49:380-92. [PMID: 21665828 DOI: 10.1093/icb/icp019] [Citation(s) in RCA: 111] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Since all life processes depend on energy, the endocrine control of energy metabolism is one of the driving forces for the performance of an individual. Here, we review the literature on the key players in the endocrine regulation of energy homeostasis in insects, the adipokinetic hormones. These pleiotropic peptides not only control dynamic performance traits (flight, swimming, walking) but also regulatory performance traits (egg production, larval growth, and molting). Adipokinetic hormone is released into the hemolymph during intense muscular activity (flight) and also during apparently less energy-demanding locomotory activities, such as swimming and even walking, and, finally, activates the catabolic enzymes phosphorylase and/or triacylglycerol lipase that mobilize carbohydrates and/or lipids and proline, respectively. At the same time, anabolic processes such as the synthesis of protein, lipid, and glycogen are inhibited. Furthermore, adipokinetic hormones affect locomotory activity via neuromodulatory mechanisms that apparently employ biogenic amines. During oogenesis, it is thought that adipokinetic hormone performs similar tasks, because energetic substrates have to be mobilized and transported from the fat body to the ovaries in order to support oocyte growth. Inhibition of anabolic processes by exogenous adipokinetic hormone results in females that lay fewer and smaller eggs. Much less is known about the role of adipokinetic hormones during larval development and during molting but in this case energy homeostasis has to be tightly regulated as well: in general, during the early phase of a larval instar intake of food prevails and the energy stores of the fat body are established, whereas, prior to the molt, insects stop feeding and mobilize energy stores in the fat body, thereby fueling energy-demanding processes such as the formation of the new cuticle and the emergence from the old one. From the few data available to date, it is clear that adipokinetic hormones are involved in the regulation of these events in larvae.
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Affiliation(s)
- Matthias W Lorenz
- Department of Animal Physiology, University of Bayreuth, 95440 Bayreuth, Germany.
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61
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Gäde G, Marco HG. Peptides of the adipokinetic hormone/red pigment-concentrating hormone family with special emphasis on Caelifera: primary sequences and functional considerations contrasting grasshoppers and locusts. Gen Comp Endocrinol 2009; 162:59-68. [PMID: 18652831 DOI: 10.1016/j.ygcen.2008.06.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/07/2008] [Revised: 06/15/2008] [Accepted: 06/25/2008] [Indexed: 10/21/2022]
Abstract
The presented work is a hybrid of an overview and an original research paper. First, we review briefly the structure, biosynthesis, release, mode of action and function of those peptides that constitute the adipokinetic/red pigment-concentrating family. Second, we collate the data on primary sequences available for caeliferan orthoptera, i.e. grasshoppers and locusts, and add a number of new data from previously unpublished work. The data are interpreted in conjunction with morphological and molecular biology data with respect to phylogenetic relationships of these various taxa. Finally, we discuss the differences between the adipokinetic response of grasshoppers and locusts to corpus cardiacum extract or synthetic adipokinetic hormone with regard to flight ability, phase polymorphism, age, presence of adipokinetic hormones, lipophorin system and other parameters. It appears that the higher hyperlipaemic response is always correlated with pronounced flight ability.
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Affiliation(s)
- Gerd Gäde
- Zoology Department, University of Cape Town, Privag Bag, Rondebosch ZA-7700, South Africa.
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62
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Gäde G. Peptides of the Adipokinetic Hormone/Red Pigment-Concentrating Hormone Family. Ann N Y Acad Sci 2009; 1163:125-36. [DOI: 10.1111/j.1749-6632.2008.03625.x] [Citation(s) in RCA: 91] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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63
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Gäde G, Simek P, Marco HG. The first identified neuropeptide in the insect order Megaloptera: a novel member of the adipokinetic hormone family in the alderfly Sialis lutaria. Peptides 2009; 30:477-82. [PMID: 18755230 DOI: 10.1016/j.peptides.2008.07.022] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/30/2008] [Revised: 07/30/2008] [Accepted: 07/30/2008] [Indexed: 10/21/2022]
Abstract
This is the first report on the structural identity of a neuropeptide of the insect order Megaloptera. A peptide was isolated and sequenced from the retrocerebral corpora cardiaca glands of the alderfly, Sialis lutaria. The sequence of the peptide was deduced from the multiple MS(N) electrospray mass data as that of an octapeptide: pGlu-Ile/Leu-Thr-Phe-Thr-Pro-Ser-Trp amide. The ambiguity about the amino acid at position 2, Leu or Ile, was solved by comparing retention time on reversed-phase HPLC and establishing co-elution with the synthetic Leu(2)-form which also had exactly the same MS(2) mass spectra as the natural peptide. The sequence represents a novel peptide of the adipokinetic hormone family which has already more than 40 members. Interestingly, the primary structure is identical to that predicted from genome information for the adipokinetic hormone of the yellow fever mosquito, Aedes aegypti. Since alderflies are not known for their active flight metabolism but produce a rather high number of eggs, it is anticipated that the alderfly is a good study object to establish a possible role of the novel peptide to regulate fat mobilization from the fat body and transport into the egg, thereby playing a role in the control of reproductive processes.
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Affiliation(s)
- Gerd Gäde
- Zoology Department, University of Cape Town, Private Bag, ZA-7701 Rondebosch, South Africa.
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64
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Adipokinetic hormone signaling through the gonadotropin-releasing hormone receptor modulates egg-laying in Caenorhabditis elegans. Proc Natl Acad Sci U S A 2009; 106:1642-7. [PMID: 19164555 DOI: 10.1073/pnas.0809881106] [Citation(s) in RCA: 115] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
In mammals, hypothalamic gonadotropin-releasing hormone (GnRH) is a neuropeptide that stimulates the release of gonadotropins from the anterior pituitary. The existence of a putative functional equivalent of this reproduction axis in protostomian invertebrates has been a matter of debate. In this study, the ligand for the GnRH receptor in the nematode Caenorhabditis elegans (Ce-GnRHR) was found using a bioinformatics approach. The peptide and its precursor are reminiscent of both insect adipokinetic hormones and GnRH-preprohormone precursors from tunicates and higher vertebrates. We cloned the AKH-GnRH-like preprohormone and the Ce-GnRHR and expressed the GPCR in HEK293T cells. The GnRHR was activated by the C. elegans AKH-GnRH-like peptide (EC(50) = 150 nM) and by Drosophila AKH and other nematode AKH-GnRHs that we found in EST databases. Analogous to both insect AKH receptor and vertebrate GnRH receptor signaling, Ce-AKH-GnRH activated its receptor through a Galpha(q) protein with Ca(2+) as a second messenger. Gene silencing of Ce-GnRHR, Ce-AKH-GnRH, or both resulted in a delay in the egg-laying process, comparable to a delay in puberty in mammals lacking a normal dose of GnRH peptide or with a mutated GnRH precursor or receptor gene. The present data support the view that the AKH-GnRH signaling system probably arose very early in metazoan evolution and that its role in reproduction might have been developed before the divergence of protostomians and deuterostomians.
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65
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Gäde G, Marco HG, Simek P, Audsley N, Clark KD, Weaver RJ. Predicted versus expressed adipokinetic hormones, and other small peptides from the corpus cardiacum-corpus allatum: a case study with beetles and moths. Peptides 2008; 29:1124-39. [PMID: 18448200 DOI: 10.1016/j.peptides.2008.03.002] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/17/2007] [Revised: 02/29/2008] [Accepted: 03/05/2008] [Indexed: 11/16/2022]
Abstract
This mass spectrometric study confines itself to peptide masses in the range of 500-1500Da. Adipokinetic hormones (AKHs) that are predicted from the genome of the red flour beetle, Tribolium castaneum, and the silk moth, Bombyx mori, are shown to exist as expressed peptides in the corpora cardiaca (CC) of the respective species as evidenced by various mass spectrometric methods. Additionally, some related species were included in this study, such as the tenebrionid beetles Tribolium brevicornis and Tenebrio molitor, as well as the moths Spodoptera frugiperda, Spodoptera littoralis, Mamestra brassicae and Lacanobia oleracea, to investigate whether AKH peptides are structurally conserved in the same genus or family. Interestingly, the AKH peptide of T. brevicornis is identical to that of T. molitor but not to the ones of its close relative T. castaneum. Moreover, other peptides in T. brevicornis, such as various FXPRL amides (=pyrokinins), also match the complement in T. molitor but differ from those in T. castaneum. All the CC of beetles lacked the signal for the mass of the peptide corazonin. All moths have the nonapeptide Manse-AKH expressed in their CC. In addition, whereas the silk moth has the decapeptide Bommo-AKH as a second peptide, all other moths (all noctuids) express the decapeptide Helze-HrTH. In M. brassicae and L. oleracea a novel amidated Gly-extended Manse-AKH is found as a possible third AKH. The noctuid moth species also all express the same FLRF amide-I, corazonin, and a group-specific isoform of a gamma-PGN-(=gamma-SGNP) peptide. In L. oleracea, however, the latter peptide has a novel sequence which is reported for the first time, and the peptide is code-named Lacol-PK.
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Affiliation(s)
- Gerd Gäde
- Zoology Department, University of Cape Town, Private Bag, ZA-7701 Rondebosch, South Africa.
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Kaufmann C, Brown MR. Regulation of carbohydrate metabolism and flight performance by a hypertrehalosaemic hormone in the mosquito Anopheles gambiae. JOURNAL OF INSECT PHYSIOLOGY 2008; 54:367-77. [PMID: 18062987 PMCID: PMC2267862 DOI: 10.1016/j.jinsphys.2007.10.007] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2007] [Revised: 10/20/2007] [Accepted: 10/22/2007] [Indexed: 05/11/2023]
Abstract
The role of adipokinetic hormones (AKHs) in the regulation of carbohydrate and lipid metabolism and flight performance was evaluated for females of the African malaria mosquito, Anopheles gambiae. Injection of various dosages of synthetic Anoga-AKH-I increased carbohydrate levels in the haemolymph and reduced glycogen reserves in sugar-fed females but did not affect lipid levels. Anoga-AKH-I enhanced the flight performance of both intact and decapitated sugar-fed females, during a 4 h flight period. Anoga-AKH-II had no effect on carbohydrate or lipid levels or flight performance, thus its function remains unknown. Targeted RNA-interference lowered Anoga-AKH receptor expression in sugar-fed females, consequently injections of Anoga-AKH-I failed to mobilize glycogen reserves. Taken together, these results show that a primary role for the neurohormone, Anoga-AKH-I, is to elevate trehalose levels in the haemolymph of female mosquitoes.
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Abdel-Latief M, Hoffmann KH. The adipokinetic hormones in the fall armyworm, Spodoptera frugiperda: cDNA cloning, quantitative real time RT-PCR analysis, and gene specific localization. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2007; 37:999-1014. [PMID: 17785188 DOI: 10.1016/j.ibmb.2007.05.007] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2007] [Revised: 05/16/2007] [Accepted: 05/16/2007] [Indexed: 05/17/2023]
Abstract
Small neuropeptides of the adipokinetic/red pigment-concentrating hormone (AKH/RPCH) family regulate energy metabolism in insects. Within lepidopterans, the nonapeptide Manduca sexta AKH (Manse-AKH) represents a widely occurring AKH, whereas the decapeptide Helze-HrTH (at first isolated from Helicoverpa zea) seems to be restricted to moths. Here we report the identification of the Manse-AKH-like Spofr-AKH 1 and the Helze-HrTH-like Spofr-AKH 2 prohormone precursors from the fall armyworm, Spodoptera frugiperda. Moreover, by PCR screening of a random primer cDNA library and by RACE, three 668, 835 and 1008 bp cDNA sequences were obtained, which encode putative translation products of 67-74 amino acids, each containing one copy of a peptide sequence that in its processed form has the sequence of QLTFSSGW-amide (Spofr-AKH 3). Another cDNA sequence of 634 bp encodes a putative translation product of 40 amino acids, potentially leading to one copy of an elongated, non-amidated Helze-HrTH (pQLTFSSGWGNCTS-OH; Spofr-AKH 4). Q-RT-PCR analysis showed that the Spofr-AKH mRNAs are expressed in 2d-old female brain/corpora cardiaca complexes, but also in ovaries, midgut, fat body, accessory glands and muscle tissues. Expression was also found in the ovaries of 4d-old females. Whole-mount in situ RT-PCR analysis with ovaries from 2d-old females showed that the Spofr-AKH 2 and Spofr-AKH 4 were mainly localized in the germarium (phase 3), whereas the Spofr-AKH 1, and the three mRNA isoforms of Spofr-AKH 3 were localized at the end of the vitellarium and in the fully developed oocytes (phase 1 and 2). The results suggest that Spofr-AKH genes play a role in the regulation of oocyte maturation in S. frugiperda.
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Affiliation(s)
- Mohatmed Abdel-Latief
- Department of Applied Zoology/Animal Ecology; Institute of Biology; Free University Berlin, 12163 Berlin, Germany.
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Gäde G, Simek P, Marco HG. A novel adipokinetic peptide in a water boatman (Heteroptera, Corixidae) and its bioanalogue in a saucer bug (Heteroptera, Naucoridae). Peptides 2007; 28:594-601. [PMID: 17215060 DOI: 10.1016/j.peptides.2006.11.019] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/24/2006] [Revised: 11/27/2006] [Accepted: 11/28/2006] [Indexed: 10/23/2022]
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.
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Affiliation(s)
- Gerd Gäde
- Zoology Department, University of Cape Town, Private Bag, ZA-7701 Rondebosch, South Africa.
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