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Gerd Gade - One of the best experts on this subject based on the ideXlab platform.
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a novel adipokinetic peptide from the Corpus Cardiacum of the primitive caeliferan pygmy grasshopper tetrix subulata caelifera tetrigidae
Peptides, 2015Co-Authors: Gerd Gade, Petr Simek, Heather G MarcoAbstract:Abstract The basal caeliferan family Tetrigidae is investigated to identify neuropeptides belonging to the adipokinetic hormone (AKH) family. The pygmy grasshopper Tetrix subulata contains in its Corpus Cardiacum two octapeptides as revealed by liquid chromatography coupled to electrospray ionization mass spectrometry. The less abundant peptide is the well-known Schgr-AKH-II (pELNFSTGW amide) which is suggested to be the ancestral AKH of Caelifera and Ensifera. The second peptide, Tetsu-AKH (pEFNFTPGW amide), is novel and quite unusual with its third aromatic residue at position 2. It is thought to be autapomorphic for Caelifera. Tetsu-AKH has hyperlipemic activity in T. subulata and in Schistocerca gregaria .
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five functional adipokinetic peptides expressed in the Corpus Cardiacum of the moth genus hippotion lepidoptera sphingidae
Regulatory Peptides, 2013Co-Authors: Gerd Gade, Petr Simek, Kevin D Clark, Heather G MarcoAbstract:Abstract This is the first study that finds five adipokinetic hormones (AKHs) in the Corpus Cardiacum of an insect. From two species of the sphingid moth genus Hippotion , eson and celerio , three novel and two known AKHs were isolated and sequenced by deduction from multiple MS n electrospray mass data: two octapeptides are pGlu-Leu-Thr-Phe-Thr-Ser-Ser-Trp amide (denoted Hipes-AKH-I) and its Thr 7 analogue (Hipes-AKH-II); two nonapeptides are pGlu-Leu-Thr-Phe-Thr-Ser-Ser-Trp-Gly amide (Manse-AKH) and its Thr 7 analogue (Hipes-AKH-III), as well as a decapeptide pGlu-Leu-Thr-Phe-Ser-Ser-Gly-Trp-Gly-Gln amide (Manse-AKH-II). All sequences were confirmed by identical behaviour of natural and synthetic peptides in reversed-phase HPLC and liquid chromatography coupled to electrospray mass spectrometry, resulting in identical retention times and tandem mass spectral data. High resolution mass spectrometry and retention time data also confirmed that the amino acid at position 10 in Manse-AKH-II is Gln and not the isobaric Lys. Conspecific injections of all five peptides in synthetic form and low doses caused hyperlipaemia in H. eson . Our results and pertaining literature suggest that five genes code for the mature peptides, which are very likely released during flight to provide energy for long distance migration in this genus via lipid oxidation; as all five peptides are active at low doses in a conspecific bioassay, it may be speculated, but not proven, that there is only one AKH receptor present in Hippotion that can bind all five peptides with high affinity.
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Adipokinetic and hyperglycaemic factors of different insect species: Separation with high performance liquid chromatography
Journal of Insect Physiology, 2003Co-Authors: Gerd GadeAbstract:Abstract Corpus Cardiacum extracts from the phasmids, Carausius morosus, Cuniculina impigra, Sipyloidea sipylus, Acrophylla wuelfingi, Eurycantha goliath, Bacillus rossius and Extatosoma tiaratum, from the Orthopterans, Locusta migratoria and Gryllus bimaculatus, from the Dictyopterans, Periplaneta americana, Gromphadorrhina coquereliana and Blaberus craniifer, from the Coleopterans Tenebrio molitor and Pachnoda sp., synthetic adipokinetic hormone and synthetic crustacean red pigment-concentrating hormone (RPCH) were injected into locusts, cockroaches and ligated stick insects as bioassay systems for adipokinetic and hyperglycaemic substances, respectively. The locust and cockroach bioassay gave positive results with all Corpus Cardiacum material tested (however the lipid response in locusts upon injection of T. molitor Corpus Cardiacum extract was very poor). The stick insect bioassay was quite specific for stick insect Corpus Cardiacum material; only Corpus Cardiacum extracts from a few other species (G. bimaculatus, P. americana, G. coquereliana and Pachnoda sp.) showed weak activity. All other extracts, including synthetic adipokinetic hormone and RPCH, failed to induce a response. Separations of Corpus Cardiacum extracts from L. migratoria, P. americana, T. molitor, C. morosus and S. sipylus were achieved on reversed-phase high-performance liquid chromatography (RP-HPLC). Locust Corpus Cardiacum extract showed two absorbance peaks with adipokinetic activity, adipokinetic hormones I and II. The peaks with hyperglycaemic activity from P. americana Corpus Cardiacum extracts had different retention times to those of locust adipokinetic hormones I and II. Stick insect Corpus Cardiacum extracts revealed also 2 absorbance peaks with adipokinetic activity, the major one co-eluting with RPCH. The active compound from Corpus Cardiacum extracts of T. molitor appeared to elute close to locust adipokinetic hormone I.
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Studies on the hypertrehalosaemic factor from the Corpus Cardiacum/Corpus allatum complex of the beetle, tenebrio molitor
Comparative Biochemistry and Physiology Part A: Physiology, 2003Co-Authors: Gerd GadeAbstract:Abstract 1. 1. The Corpus Cardiacum/Corpus allatum complex (CC/CA) of the beetle, Tenebrio molitor, contains a factor which elicits hyperlipaemia in migratory locusts and hypertrehalosaemia in American cockroaches. Appreciable amounts of this factor are found only in the CC/CA. 2. 2. The lipid and carbohydrate elevations were time-dependent (maximum effect: 90 min and 120 min after injection, respectively), and were also dose-dependent. Significant hypertrehalosaemic and adipokinetic effects were obtained with 0.1 and 0.25 CC/CA equivalents, respectively; and 1.0 and 3.0 gland equivalents, respectively, were needed for maximal or near-maximal responses. lil]3. Age-related changes of both biological activities were observed in beetle CC/CA; young adults (less than 3 days after imaginai ecdysis) had smaller quantities of bioactive material stored in their CC/CA. 3. 4. T. molitor CC/CA extracts were also able to activate endogenous fat body glycogen phosphorylase in adult beetles in a dose-dependent manner; a maximal activation was achieved upon injection of 0.2 CC/CA equivalents. 4. 5. Fractionation of a methanolic extract of CC/CA by reversed-phase high performance liquid chromatography shows that the hypertrehalosaemic as well as the adipokinetic and phosphorylaseactivating activities, are probably confined to a single absorbance peak.
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Involvement of adenosine 3′:5′-cyclic monophosphate in lipid mobilization in Locusta migratoria
Insect Biochemistry, 2003Co-Authors: Gerd Gade, D A HolwerdaAbstract:The role of cyclic AMP in hormone-induced lipid mobilization in Locusta migratoria was investigated. Injection of a Corpus Cardiacum extract into adult female locusts resulted in an increased level of cyclic AMP in the fat body. The cAMP concentration is maximal at about 5 min of incubation and returns to the resting level after about 10 min. The dose-response curve is linear up to about 0.01 Corpus Cardiacum pair equivalents. Dibutyryl-cyclic AMP mimics the lipid mobilizing effect of Corpus Cardiacum extract. After flight the cyclic AMP concentration in fat body increased. Injection of Corpus Cardiacum extract had no effect on flight muscle cyclic AMP concentration.
Mark L Proefke - One of the best experts on this subject based on the ideXlab platform.
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a tryptophan substituted member of the akh rpch family isolated from a stick insect Corpus Cardiacum
Biochemical and Biophysical Research Communications, 1992Co-Authors: Gerd Gade, Kenneth L Rinehart, Roland Kellner, Mark L ProefkeAbstract:Abstract A neuropeptide, Cam-HrTH-I, has been isolated from the Corpus Cardiacum of the Indian stick insect Carausius morosus. The peptide causes hyperlipaemia in Locusta migratoria and hypertrehalosaemia in Periplaneta americana and is related to the previously isolated Cam-HrTH-II (pGlu-Leu-Thr-Phe-Thr-Pro-Asn-Trp-Gly-Thr-NH2) by substitution, apparently by a hexose, on the Trp residue. This appears to be the first example of such substitution on a Trp residue.
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A tryptophan-substituted member of the AKH/RPCH family isolated from a stick insect Corpus Cardiacum
Biochemical and Biophysical Research Communications, 1992Co-Authors: Gerd Gade, Kenneth L Rinehart, Roland Kellner, Mark L ProefkeAbstract:Abstract A neuropeptide, Cam-HrTH-I, has been isolated from the Corpus Cardiacum of the Indian stick insect Carausius morosus. The peptide causes hyperlipaemia in Locusta migratoria and hypertrehalosaemia in Periplaneta americana and is related to the previously isolated Cam-HrTH-II (pGlu-Leu-Thr-Phe-Thr-Pro-Asn-Trp-Gly-Thr-NH2) by substitution, apparently by a hexose, on the Trp residue. This appears to be the first example of such substitution on a Trp residue.
Roland Kellner - One of the best experts on this subject based on the ideXlab platform.
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a tryptophan substituted member of the akh rpch family isolated from a stick insect Corpus Cardiacum
Biochemical and Biophysical Research Communications, 1992Co-Authors: Gerd Gade, Kenneth L Rinehart, Roland Kellner, Mark L ProefkeAbstract:Abstract A neuropeptide, Cam-HrTH-I, has been isolated from the Corpus Cardiacum of the Indian stick insect Carausius morosus. The peptide causes hyperlipaemia in Locusta migratoria and hypertrehalosaemia in Periplaneta americana and is related to the previously isolated Cam-HrTH-II (pGlu-Leu-Thr-Phe-Thr-Pro-Asn-Trp-Gly-Thr-NH2) by substitution, apparently by a hexose, on the Trp residue. This appears to be the first example of such substitution on a Trp residue.
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A tryptophan-substituted member of the AKH/RPCH family isolated from a stick insect Corpus Cardiacum
Biochemical and Biophysical Research Communications, 1992Co-Authors: Gerd Gade, Kenneth L Rinehart, Roland Kellner, Mark L ProefkeAbstract:Abstract A neuropeptide, Cam-HrTH-I, has been isolated from the Corpus Cardiacum of the Indian stick insect Carausius morosus. The peptide causes hyperlipaemia in Locusta migratoria and hypertrehalosaemia in Periplaneta americana and is related to the previously isolated Cam-HrTH-II (pGlu-Leu-Thr-Phe-Thr-Pro-Asn-Trp-Gly-Thr-NH2) by substitution, apparently by a hexose, on the Trp residue. This appears to be the first example of such substitution on a Trp residue.
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the sequence of acheta adipokinetic hormone and the variation in Corpus Cardiacum content and hyperlipaemic response with age
Zeitschrift für Naturforschung C, 1990Co-Authors: Joseph Woodring, Roland Kellner, Gerd GadeAbstract:The principle neuropeptide separated by reversed-phase liquid chromatography RP -HPLC from extracts of the corpora cardica of Acheta domesticus showed strong adipokinetic activity when injected into Acheta. The N -terminal pyroglutamate of the peptide was removed by enzymatic digestion, and the remaining peptide sequenced. The structure is identical to the peptide Grb -AKH previously described from the Corpus Cardiacum (CC) of Gryllus bimaculatus (pGlu - Val - Asn - Phe - Ser - Thr - Gly - Trp - NH₂). The ED₅₀ was (0.8 pmol) and saturation was achieved with injection of 2 pmol of synthetic Grb-AKH . The time to maximum hyperlipaemic response was 90 -120 min. The response of the fat body to injected synthetic Grb- AKH doubled in 4 days during the last stadium , but was never greater than half the maximum response of the adult stage. The adult adipokinetic response doubled from the first to the fourth day then gradually declined through day 16. The increased AKH response was timecorrelated to fat storage in the larvae and to lipid diposits in the oocytes in the adult. Synthetic Grb -AKH activated glycogen phosphorylase in the fat body of Acheta. The amount of Grb- AKH present in the CC changed very little throughout the last larval stadium and through the first 9 days of the adult stage, averaging about 15 pmol/gland pair. A second peptide (a hexadecapeptide) was isolated from the CC of Acheta and sequenced. Its structure is identical to a putative diuretic hormone previously described in Acheta.
Kenneth L Rinehart - One of the best experts on this subject based on the ideXlab platform.
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a tryptophan substituted member of the akh rpch family isolated from a stick insect Corpus Cardiacum
Biochemical and Biophysical Research Communications, 1992Co-Authors: Gerd Gade, Kenneth L Rinehart, Roland Kellner, Mark L ProefkeAbstract:Abstract A neuropeptide, Cam-HrTH-I, has been isolated from the Corpus Cardiacum of the Indian stick insect Carausius morosus. The peptide causes hyperlipaemia in Locusta migratoria and hypertrehalosaemia in Periplaneta americana and is related to the previously isolated Cam-HrTH-II (pGlu-Leu-Thr-Phe-Thr-Pro-Asn-Trp-Gly-Thr-NH2) by substitution, apparently by a hexose, on the Trp residue. This appears to be the first example of such substitution on a Trp residue.
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A tryptophan-substituted member of the AKH/RPCH family isolated from a stick insect Corpus Cardiacum
Biochemical and Biophysical Research Communications, 1992Co-Authors: Gerd Gade, Kenneth L Rinehart, Roland Kellner, Mark L ProefkeAbstract:Abstract A neuropeptide, Cam-HrTH-I, has been isolated from the Corpus Cardiacum of the Indian stick insect Carausius morosus. The peptide causes hyperlipaemia in Locusta migratoria and hypertrehalosaemia in Periplaneta americana and is related to the previously isolated Cam-HrTH-II (pGlu-Leu-Thr-Phe-Thr-Pro-Asn-Trp-Gly-Thr-NH2) by substitution, apparently by a hexose, on the Trp residue. This appears to be the first example of such substitution on a Trp residue.
J E Phillips - One of the best experts on this subject based on the ideXlab platform.
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isolation of a neuropeptide from locust Corpus Cardiacum which influences ileal transport
The Journal of Experimental Biology, 1992Co-Authors: N Audsley, C Mcintosh, J E PhillipsAbstract:1. Schistocerca gregaria ion-transport peptide (Scg-ITP) was isolated from aqueous extracts of the Corpus Cardiacum by a four-step procedure, utilizing reverse-phase high-performance liquid chromatography for separation and stimulation of a Cl(-)-dependent short-circuit current (Isc) across locust ilea as the bioassay. 2. Scg-ITP has an unblocked N terminus and an apparent relative molecular mass of 7700. Thirty-one residues (of an estimated 65) were identified by sequence analysis. 3. Scg-ITP is structurally related to a crustacean family of neuropeptides which includes the crustacean hyperglycaemic hormones from the shore crab Carcinus maenas and the crayfish Orconectes limosus and moult-inhibiting hormone and vitellogenesis-inhibiting hormone from the lobster Homarus americanus. 4. Scg-ITP has no sequence homology with neuroparsins (Nps). Nps are the only other neuropeptides isolated to date that might regulate reabsorption in an insect hindgut (rectum).
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actions of ion transport peptide from locust Corpus Cardiacum on several hindgut transport processes
The Journal of Experimental Biology, 1992Co-Authors: N Audsley, C Mcintosh, J E PhillipsAbstract:1. Schistocerca gregaria ion-transport peptide (Scg-ITP), a neuropeptide isolated from locust corpora cardiaca, stimulates ileal Cl- transport (Isc) in a dose-dependent manner and causes increases in Na+, K+ (IK) and fluid reabsorption (Jv) as previously observed with crude extracts of Corpus Cardiacum and with cyclic AMP. Unlike cyclic AMP, Scg-ITP does not stimulate ileal NH4+ secretion. 2. H+ secretion (JH) in the ileum, which is not affected by cyclic AMP, is almost completely abolished by Scg-ITP. Although ITP may act via cyclic AMP as second messenger to stimulate NaCl, KCl and fluid reabsorption, it apparently acts through a different intracellular pathway to influence JH. 3. Scg-ITP is unlikely to be the chloride transport stimulating hormone previously reported to act on the rectum, because it did not produce a maximum rectal Isc response and had no effect on either rectal Jv (which is Cl--dependent) or IK.
