Chemical characterization of a novel peptide from the neuroendocrine light yellow cells of Lymnaea stagnalis.

The neuroendocrine light yellow cells of Lymnaea stagnalis form two clusters of cells in the visceral and right parietal ganglion, respectively. These cells are endogenously bursting neurons whose activities are modified during egg-laying and feeding. Using gel permeation chromatography and reverse phase HPLC we have purified two highly related novel peptides from the light yellow cells. These peptides differ only in length, due to truncation of the amino-terminal aspartic acid residue, which causes a major shift in the charge of the molecule. We conclude that the longer peptide is the immediate precursor of the shorter form. Using whole mount immunocytochemistry, it was confirmed that the light yellow cells produce these peptides.