A novel peptide in the AKH/RPCH family isolated from the corpora cardiaca of the Emperor dragonfly, Anax imperator

Using a heterologous (in locusts and cockroaches) and a homologous bioassay we have isolated the neuropeptide pGlu-Val-Asn-Phe-Ser-Pro-Ser-Trp-NH2 from extracts of corpora cardiaca of the Emperor dragonfly, Anax imperator. The sequence elucidation was achieved by Edman degradation of the deblocked peptide and by electrospray mass spectrometry. Low concentrations of the synthetic peptide injected into the Emperor dragonfly increased the hemolymph lipid concentration, suggesting a possible role of the peptide in lipid homeostasis during flight. Therefore, it is named Ani-AKH, Anax imperator adipokinetic hormone.