The crustacean hyperglycemic hormone precursors a and b of the Norwey lobster differ in the proprohormone but not in the mature peptide

The neuro-endocrine X-organ sinus-gland complex of crustaceans produces and releases the neuropeptides of the crustacean hyperglycemichormone (cHH)/molt-inhibiting hormone (MIH)/gonad-inhibiting hormone (GIH) family that regulate important physiological processes, suchas growth, reproduction and molting.We cloned two full-length cDNAs encoding the preprocHH-A and preprocHH-B of the Norway lobsterNephrops norvegicus of 132 and 131 amino acid residues. The two cHHs differ in the preprohormone but not in the mature peptide sequence.The mature cHH was expressed in bacteria as GST fusion protein that, in bioassay, shows a hyperglycemic activity similar to that of native cHH present in an eyestalk extract.© 2004 Elsevier Inc. All rights reserved.