A NEW OPIOID PEPTIDE PREDICTED FROM CLONED CDNAS FROM SKIN OF PACHYMEDUSA DANICOLOR AND AGALYCHNIS-ANNAE

We have isolated a cDNA encoding a precursor of dermorphin from the sk in of Pachymedusa dacnicolor. Besides four copies of this opioid pepti de, the deduced sequence also contains the genetic information for a n ovel peptide Tyr-Ile-Phe-His-Leu-Met-Asp-NH2. This differs from Met-de ltorphin by the presence of Ile at position 2, In a related precursor from the skin of Agalychnis annae, the sequence of this peptide is in the 3'-untranslated region of the cloned cDNA. From earlier results me predict that in skin peptides the second residue is D-allo-Ile, We ha ve synthesized this and related peptides with different D-amino acids, and determined their delta agonist activity. The peptide with D-nor-L eu binds with high affinity to delta receptors, while that with D-allo -Ile is about 100 times less active. (C) 1998 Federation of European B iochemical Societies.