Trend plot analysis of differentially expressed glycophorin-A phosphopeptides. (A) Z-Score transformed phosphopeptide intensities of glycophorin-A peptides, which decreased in abundance in SS RBCs upon treatment with U0126 (indicated in Table2) were differentiated into groups, which either did or did not increased in AA RBCs upon addition of recombinant active ERK2 to the membrane ghosts, and plotted across four relevant treatment groups. (B) Five glycophorin-A phosphorylated peptides, which both decreased in SS RBCs upon treatment with U0126 and increased in AA RBCs upon addition of active ERK2 to the membrane ghosts plotted across all eight treatment groups. Each data-point is plotted as an average of three technical replicates. An (*) within the peptide sequence indicates the preceding residue is phosphorylated.