Figure 9

Residues lining pockets across apo IL-2 superfamily members overlap with IL-2-receptor interfaces. The residues most often involved in pocket formation (defined as those residues having the top 25% of Provar scores, ≥ 0.364 in this case) across 17 apo structures of functionally diverse IL-2 homologues are colored red on the molecular surface of IL-2 in a receptor bound conformation [PDB:2B5I]. These pocket forming residues, thus identified in a substantial subset of the apo-structures, overlap the IL-2:IL-2 receptor interfaces (A, B, C) with respectively the receptor α, β and γ chains, suggesting that the location of their receptor interaction sites is well conserved across the family despite low sequence identity.