Figure 3

Analysis of murine IL4 variation. Cartoon representations depicting human IL4 structure (PDB ID: 1H1K) were rotated (90°) to feature (A) the site 1 epitope (red) and (B) the site 2 epitope (blue). Side chains are shown for residues that are non-synonymously substituted between M. musculus and M. castaneus (yellow and orange), positively selected (H1, C3 and Q8; orange), and that comprise the mixed-charge pair responsible for the majority of the IL4Rα binding energy (E9 and R88; cyan). Site 3 epitope residues are shown in magenta. Alpha helices A, B, C and D are labeled. (All structure representation were created in PyMol, http://www.pymol.org)