Rapid evolution of NK cell receptor systems demonstrated by comparison of chimpanzees and humans.
That NK cell receptors engage fast-evolving MHC class I ligands suggests that they, too, evolve rapidly. To test this hypothesis, the structure and class I specificity of chimpanzee KIR and CD94:NKG2 receptors were determined and compared to their human counterparts. The KIR families are divergent, with only three KIR conserved between chimpanzees and humans. By contrast, CD94:NKG2 receptors are conserved. Whereas receptors for polymorphic class I are divergent, those for nonpolymorphic class I are conserved. Although chimpanzee and human NK cells exhibit identical receptor specificities for MHC-C, they are mediated by nonorthologous KIR. These results demonstrate the rapid evolution of NK cell receptor systems and imply that "catching up" with class I is not the only force driving this evolution.
Khakoo
S I
SI
Department of Structural Biology, Stanford University, California 94305, USA.
Rajalingam
R
R
Shum
B P
BP
Weidenbach
K
K
Flodin
L
L
Muir
D G
DG
Canavez
F
F
Cooper
S L
SL
Valiante
N M
NM
Lanier
L L
LL
Parham
P
P
D000818:Animals; D015703:Antigens, CD / Q000737:chemistry; D001666:Binding Sites, Antibody; D001667:Binding, Competitive / Q000276:immunology; D019070:Cell Lineage / Q000235:genetics / Q000276:immunology; D002999:Clone Cells; D017124:Conserved Sequence; D019143:Evolution, Molecular; D015395:Histocompatibility Antigens Class I / Q000378:metabolism; D006801:Humans; D007694:Killer Cells, Natural / Q000276:immunology / Q000378:metabolism*; D037181:Lectins, C-Type; D008562:Membrane Glycoproteins / Q000037:antagonists & inhibitors / Q000737:chemistry; D008969:Molecular Sequence Data; D055654:NK Cell Lectin-Like Receptor Subfamily C; D051920:NK Cell Lectin-Like Receptor Subfamily D; D002679:Pan troglodytes / Q000276:immunology*; D011971:Receptors, Immunologic / Q000037:antagonists & inhibitors / Q000096:biosynthesis / Q000737:chemistry* / Q000502:physiology*; D054340:Receptors, KIR; D055607:Receptors, Natural Killer Cell; D017386:Sequence Homology, Amino Acid; D013329:Structure-Activity Relationship
D015703:Antigens, CD; D015395:Histocompatibility Antigens Class I; C527054:KLRC1 protein, human; C497869:KLRD1 protein, human; D037181:Lectins, C-Type; D008562:Membrane Glycoproteins; D055654:NK Cell Lectin-Like Receptor Subfamily C; D051920:NK Cell Lectin-Like Receptor Subfamily D; D011971:Receptors, Immunologic; D054340:Receptors, KIR; D055607:Receptors, Natural Killer Cell