Fig. 2.

Sequence alignment of human HLA-G with HLA-E, -A2, -B44, and -CW3 as well as mouse Qa-2. The sequence alignment is divided into the three domains: α1, α2, and α3. Residues highlighted with red have 100% identity. Residues highlighted in yellow are conservatively substituted. The secondary structure of HLA-G is illustrated directly above the sequence alignment. Orange arrows indicate β-strands, and blue cylinders indicate α-helices. Residues directly interacting with the peptide are marked with a large green star, and residues interacting only via a water molecule are marked with a hollow circle (see Table 3). The loop in domain α3 involved in LIR-1/2 (ILT-2/4) binding is highlighted with a green box.