ISOLATION AND CHARACTERIZATION OF MELANOPLUS-SANGUINIPES ADIPOKINETICHORMONE - A NEW MEMBER OF THE AKH RPCH FAMILY/

A neuropeptide hormone isolated from corpora cardiaca of Melanoplus sa nguinipes was purified by HPLC. The HPLC fractions were examined for a dipokinetic activity with an in vivo bioassay. A single large UV absor bent peak was active in the mobilization of lipid while the other HPLC fractions showed no detectable activity. This large peak had a retent ion time and amino acid composition identical to synthetic Lom-AHH-I w hich was analyzed in a parallel manner. The primary sequence structure , pGlu-Leu-Asn-Phe-Thr-Pro-Asn-Trp-Gly-Thr-NH2, was determined by auto mated gas-phase Edman degradation. The peptide was deblocked prior to sequencing using pyroglutamate aminopeptidase and the sequence was con firmed with mass spectrometry. The C-terminus of the peptide was deter mined to be blocked, as indicated by the lack of digestion with carbox ypeptidase A. The knowledge of the primary sequence of Mes-AKH allows the use of a commercially available synthetic peptide and its antibodi es for use in future research with Melanoplus sanguinipes. (C) 1997 Ac ademic Press.