ISOLATION OF LYS-CONOPRESSIN-G FROM THE VENOM OF THE WORM-HUNTING SNAIL, CONUS-IMPERIALIS

Vasopressin homologs have previously been isolated from the venom of f ish-hunting cone snails. We investigated whether a vasopressin-like pe ptide is found in the worm-hunter, Conus imperialis. Using i.c. inject ions in mice, we isolated a peptide from the venom of C. imperialis wh ich induces scratching and grooming behavior characteristic of the con opressins. Biochemical characterization showed that this peptide is id entical to Lys-conopressin-G. The results led us to speculate that the vasopressin-like peptides in Conus venoms may be examples of an evolv ing conversion of endogenous peptides for specialized venom uses.