scholarly journals A novel adipokinetic octapeptide found in the damselflies Pseudagrion inconspicuum and Ischnura senegalensis

1994 ◽  
Vol 302 (2) ◽  
pp. 539-543 ◽  
Author(s):  
M P Janssens ◽  
R Kellner ◽  
G Gde
Keyword(s):  
Synthetic Peptide ◽  
Natural Compound ◽  
Laser Desorption ◽  
Reversed Phase ◽  
Edman Degradation ◽  
The Novel ◽  
Laser Desorption Ionization ◽  
Corpus Cardiacum ◽  
Adipokinetic Hormone ◽  
Adipokinetic Hormone Family

A member of the adipokinetic hormone family of peptide was identified in the damselflies Pseudagrion inconspicuum and Ischnura senegalensis using a heterologous (in migratory locusts and American cockroaches) and a homologous (in P. inconspicuum) bioassay. After isolation of the peptide by reversed-phase h.p.i.c. of corpora cardiaca, its structure was determined by automated Edman degradation and matrix-assisted laser-desorption ionization m.s. The sequence of a blocked uncharged octapeptide was established: pGlu-Val-Asn-Phe-Thr-Pro-Gly-TrpNH2. One corpus cardiacum of P. inconspicuum contains about 2.4 pmol of this novel peptide. The synthetic peptide was chromatographically indistinguishable from the natural compound, and on injection in low quantities into the damselfly P. inconspicuum, haemolymph levels of lipids were increased. It is concluded that the novel peptide may be involved in controlling lipid mobilization during flight. Hence the peptide is designated Psi-AKH, Pseudagrion inconspicuum adipokinetic hormone.

scholarly journals Isolation and structure of a novel charged member of the red–pigment-concentrating hormone-adipokinetic hormone family of peptides isolated from the corpora cardiaca of the blowfly Phormia terraenovae (Diptera)

1990 ◽  
Vol 269 (2) ◽  
pp. 309-313 ◽  
Author(s):  
G Gäde ◽  
H Wilps ◽  
R Kellner
Keyword(s):  
Periplaneta Americana ◽  
Fat Body ◽  
Locusta Migratoria ◽  
Reversed Phase ◽  
American Cockroach ◽  
Red Pigment ◽  
Adipokinetic Hormone ◽  
Migratory Locust ◽  
Corpora Cardiaca ◽  
Adipokinetic Hormone Family

A hypertrehalosaemic neuropeptide from the corpora cardiaca of the blowfly Phormia terraenovae has been isolated by reversed-phase h.p.l.c., and its primary structure was determined by pulsed-liquid phase sequencing employing Edman chemistry after enzymically deblocking the N-terminal pyroglutamate residue. The C-terminus was also blocked, as indicated by the lack of digestion when the peptide was incubated with carboxypeptidase A. The octapeptide has the sequence pGlu-Leu-Thr-Phe-Ser-Pro-Asp-Trp-NH2 and is clearly defined as a novel member of the RPCH/AKH (red-pigment-concentrating hormone/adipokinetic hormone) family of peptides. It is the first charged member of this family to be found. The synthetic peptide causes an increase in the haemolymph carbohydrate concentration in a dose-dependent fashion in blowflies and therefore is named ‘Phormia terraenovae hypertrehalosaemic hormone’ (Pht-HrTH). In addition, receptors in the fat-body of the American cockroach (Periplaneta americana) recognize the peptide, resulting in carbohydrate elevation in the blood. However, fat-body receptors of the migratory locust (Locusta migratoria) do not recognize this charged molecule, and thus no lipid mobilization is observed in this species.

The Sequence of Acheta Adipokinetic Hormone and the Variation in Corpus cardiacum Content and Hyperlipaemic Response with Age

1990 ◽  
Vol 45 (11-12) ◽  
pp. 1176-1184 ◽  
Author(s):  
Joseph Woodring ◽  
Subrata Das ◽  
Roland Kellner ◽  
Gerd Gäde
Keyword(s):  
Glycogen Phosphorylase ◽  
Fat Body ◽  
Adult Stage ◽  
Enzymatic Digestion ◽  
Reversed Phase ◽  
Acheta Domesticus ◽  
Corpus Cardiacum ◽  
Reversed Phase Liquid Chromatography ◽  
Adipokinetic Hormone ◽  
Phase Liquid

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.

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