The human major histocompatibility complex class Ib molecule HLA-E binds signal sequence-derived peptides with primary anchor residues at positions 2 and 9.
Human histocompatibility leukocyte antigen E (HLA-E) and mouse major histocompatibility complex (MHC) class Ib antigen, Qa-1, share the same substitutions at two normally conserved positions 143 and 147, which are likely to affect binding of the C terminus of peptides. Qa-1 is able to bind a peptide derived from the leader sequence of H-2 D and H-2 L molecules. We developed a peptide binding assay in vitro to compare the binding specificity of HLA-E with the mouse MHC class Ib molecule Qa-1. We demonstrate that HLA-E binds, although poorly, the peptide which binds to Qa-1 and that it also binds nonamer signal sequence-derived peptides from human MHC class I molecules. Using alanine and glycine substitutions, we could define primary anchor residues at positions 2 and 9 and secondary anchor residues at position 7 and possibly 3.
Braud
V
V
Institute of Molecular Medicine, John Radcliffe Hospital, Oxford, GB. vbraud@worf.molbiol.ox.ac.uk
Jones
E Y
EY
McMichael
A
A
D000595:Amino Acid Sequence; D000818:Animals; D002461:Cell Line, Transformed; D006680:HLA Antigens / Q000302:isolation & purification / Q000378:metabolism*; D015395:Histocompatibility Antigens Class I / Q000302:isolation & purification / Q000378:metabolism*; D006801:Humans; D007525:Isoelectric Focusing; D007739:L Cells; D051379:Mice; D009842:Oligopeptides / Q000378:metabolism; D011485:Protein Binding / Q000276:immunology; D011487:Protein Conformation; D021382:Protein Sorting Signals / Q000378:metabolism*; D000097625:HLA-E Antigens
D006680:HLA Antigens; D015395:Histocompatibility Antigens Class I; D009842:Oligopeptides; D021382:Protein Sorting Signals; D000097625:HLA-E Antigens; C032907:Q surface antigens