The Structural Basis of Ligand Recognition by Natural Killer Cell Receptors

Figure 2

Structure of inhibitory KIR molecules. (a) Structure of KIR2DL2 which is made up of two C2-like domains is shown in cartoon representation with the N-terminus and C-terminus described by a blue and red sphere, respectively. (b) Structure of KIR2DL2 in complex with the MHC class I molecule HLA-Cw3 and β2m shown in cartoon representation with bound peptide shown in ball and stick representation with yellow carbon atoms. (c) Closeup of the HLA-Cw3 : KIR2DL2 interface with interacting residues displayed in ball and stick representation. The bound peptide is shown with yellow colored carbon atoms while the interacting residues from HLA-Cw3 are shown in purple and those from the KIR molecule are shown in off-white coloring. The critical residues for HLA-KIR specificity, K44 from KIR 2DL2 and N80 from HLA Cw3 are shown in green and light-blue, respectively. (d) Closeup of the HLA-Cw4 : KIR2DL1 interface with interacting residues displayed in ball and stick representation. The bound peptide is shown with white carbon atoms while the interacting residues from HLA-Cw4 have green carbon atoms and those from KIR 2DL1 have yellow carbon atoms. The critical residues for HLA-KIR specificity, M44 from KIR 2DL1, and K80 from HLA Cw4 are shown in dark green and light green, respectively.