FIGURE 3.

Comparison of extracted ion chromatograms and multiple-reaction monitoring for semiquantitative analysis of glycosylation. EICs (A) and MRM chromatograms (B) show the relative levels of unmodified (black line), O-fucose monosaccharide (red line), and O-fucose disaccharide (blue line) glycoforms of peptides ²⁸⁹NCEQNYDDCLGHLCQNGGTCIDGISDYTCR³¹⁸ from EGF7 and ¹²¹¹QGFQGQNCELNIDDCAPNPCQNGGTCHDR¹²³⁹ from EGF31. Internal unglycosylated control peptides used were ²⁷²SNGLSYECK²⁸⁰ from EGF6 (A) and ¹²⁰⁰DLIGAYECQCR¹²¹⁰ from EGF30 (B) from samples generated in the absence of Fringe (black line) or presence of Fringe (red line). Lists of the ions used for each glycoform in the EICs and MRM chromatograms are provided in supplemental Fig. S3.