Natural variation at position 45 in the D1 domain of lineage III killer cell immunoglobulin-like receptors (KIR) has major effects on the avidity and specificity for MHC class I.

ABSTRACT: Alternative lysine and methionine residues at position 44 in the D1 domain determine the specificities of human lineage III killer cell immunoglobulin-like receptors (KIR) for the C1 and C2 epitopes of HLA-C. KIR having glutamate 44 are also present in orangutans (Popy2DLB) and chimpanzees (Pt-2DL9) but notably absent from humans. Popy2DLB exhibits broad specificity for both the C1 and C2 epitopes, whereas Pt-2DL9 has narrow specificity for C2. Mutation of phenylalanine 45 in Popy2DLB to the cysteine residue present in Pt-2DL9 was sufficient to narrow the Popy2DLB specificity to be like that of Pt-2DL9. In contrast, replacement of cysteine 45 in Pt-2DL9 by phenylalanine had no effect on its C2 specificity, but reduced the avidity. In a similar manner, replacement of phenylalanine 45 with c

SUBMITTER: Older Aguilar AM 

PROVIDER: S-EPMC3160831 | biostudies-literature | 2011 Aug

REPOSITORIES: biostudies-literature