Presence of the predicted C-flanking peptide of neuropeptide Y (CPON) in tissue extracts.

Isolation of the DNA sequence encoding neuropeptide Y (NPY) has suggested the presence of a precursor peptide consisting of 97 aminoacids. Three peptide products have been predicted from this precursor; an N terminal signal peptide, neuropeptide Y and a C terminal 30 amino acid flanking peptide. This study has demonstrated by a novel radioimmunoassay that this C-flanking peptide for NPY occurs naturally in tissues. The peptide is present in abundance throughout the central nervous system and qualitatively in both the brain and peripheral structures, it has the same distribution as NPY. Chromatographic analysis demonstrated that the measured CPON-immunoreactivity elutes in the position of the peptide synthesised according to the predicted sequence.