Novel Members of the AKH/RPCH Peptide Family: Isolation of AKH from the Corpora Cardiaca of the Two Beetle Species, Cheilomenes Lunata and Coccinella Septempunctata

Adipokinetic hormones (AKH) are synthesized in endocrine cells of the glandular corpora cardiaca, in the anterior part of the retrocerebral complex. AKH plays an important role in the metabolism of carbohydrates that fuel energydepleting activities such as flight and walking. To date, the primary sequences of eight isoforms from various beetle species have been elucidated. In this study, the glandular part of the CC from two Ladybird beetles, Cheilomenes lunata and Coccinella septempunctata were directly analysed by MALDI-TOF mass spectrometry. Subsequently, the amino acid sequences of both putative novel AKHs were confirmed by tandem mass spectrometry.