HLA-E: A Novel Player for Histocompatibility

Figure 1

C-terminal peptide residues mediate contact between the complex and the CD94/NKG2A receptor. This structure represents the interactions between the CD94/NKG2A receptor and the complex (PDB: 3CDG) [4]. The CD94 subunit (raspberry) dominates the recognition of the peptide (orange sticks) with several contacts including hydrogen bonds of Ser110 to the peptide’s p5-Arg and Gln112 to p6-Thr. The peptide’s p8-Phe is surrounded by a polar pocket created by Asn156, Asn158, and Asn160 and van der Waals contacts with Phe114. p5-Arg also builds a salt bridge to Glu152 of the HLA-E heavy chain (pale teal) that may prevent more charged interactions with CD94/NKG2A. Residue Pro171 of NKG2A (pale grey) interacts with p5-Arg by van der Waals interactions. Hydrogen bonds are represented as black dashed lines, and salt bridges are given in blue.