Fig. 3.

Representative base peak chromatograms of the secretopeptidome from unstimulated (top) and stimulated (bottom) cells. Samples without gel filtration chromatography were analyzed. Major processing products of CT and CGRP precursors are illustrated along with arrows pointing at their peaks in the chromatogram. The base peaks marked with asterisks at 20.85 min (unstimulated) and 21.50 min (stimulated) are intact ubiquitin. SP, signal peptide; N-term pro., N-terminal propeptide; Kat., katacalcin. Base peaks at 8.75 and 15.03 min in the top panel were unrelated to peptide signals. RT, retention time; NL, normalized ion intensity.