Figure 3.

CXCL9 cleavage sites. CXCL9 has a signal sequence that is cleaved before secretion. Blue box indicates an N-terminal peptide corresponding to predicted beta sheet secondary structure. Red box indicates a C-terminal peptide corresponding to predicted amphipathic alpha helix secondary structure. R and Abx represent CXCR3 receptor activation and antibiotic activities, respectively. ND, N, and Y, denote not determined, negative, and positive (yes) activities, respectively. Endogenous CXCL9 has several truncated forms. These forms have been separated into two groups: high molecular weight (High MW) and low molecular weight (Low MW) groups for receptor activation. SpeB and SufA are two bacterial enzymes that cleave CXCL9. Arrows indicate where the processing sites are located.