Alignment of human, murine and viral ligands for the human and the murine lymphotactin receptor. The upper panel shows the primary structure of the two HHV8 encoded chemokines, vCCL2, vCCL3, the human lymphotactin XCL1 and the murine lymphotactin mXCL1 aligned using CLUSTALW from Kyoto University Bioinformatics Center. Identical amino acids are shown in white on black, whereas similar amino acids are shown in black on light grey. Cysteines are shown in black on yellow and presumed disulfide bridges are marked with an asterisk. Likely O-glycosylation sites using the CBS prediction server are marked white on blue. The secondary structure of XCL1 as determined by NMR is indicated by the line above the alignment .