A novel system of polymorphic and diverse NK cell receptors in primates.
There are two main classes of natural killer (NK) cell receptors in mammals, the killer cell immunoglobulin-like receptors (KIR) and the structurally unrelated killer cell lectin-like receptors (KLR). While KIR represent the most diverse group of NK receptors in all primates studied to date, including humans, apes, and Old and New World monkeys, KLR represent the functional equivalent in rodents. Here, we report a first digression from this rule in lemurs, where the KLR (CD94/NKG2) rather than KIR constitute the most diverse group of NK cell receptors. We demonstrate that natural selection contributed to such diversification in lemurs and particularly targeted KLR residues interacting with the peptide presented by MHC class I ligands. We further show that lemurs lack a strict ortholog or functional equivalent of MHC-E, the ligands of non-polymorphic KLR in "higher" primates. Our data support the existence of a hitherto unknown system of polymorphic and diverse NK cell receptors in primates and of combinatorial diversity as a novel mechanism to increase NK cell receptor repertoire.
Averdam
Anne
A
Department of Primate Genetics, German Primate Centre, Göttingen, Germany.
Petersen
Beatrix
B
Rosner
Cornelia
C
Neff
Jennifer
J
Roos
Christian
C
Eberle
Manfred
M
Aujard
Fabienne
F
Münch
Claudia
C
Schempp
Werner
W
Carrington
Mary
M
Shiina
Takashi
T
Inoko
Hidetoshi
H
Knaust
Florian
F
Coggill
Penny
P
Sehra
Harminder
H
Beck
Stephan
S
Abi-Rached
Laurent
L
Reinhardt
Richard
R
Walter
Lutz
L
D000818:Animals; D002460:Cell Line; D019143:Evolution, Molecular; D006649:Histocompatibility Antigens / Q000235:genetics / Q000276:immunology; D006801:Humans; D051379:Mice; D008958:Models, Molecular; D051920:NK Cell Lectin-Like Receptor Subfamily D / Q000737:chemistry / Q000235:genetics* / Q000276:immunology*; D010802:Phylogeny; D011110:Polymorphism, Genetic; D020836:Protein Structure, Quaternary; D011443:Strepsirhini / Q000235:genetics* / Q000276:immunology*
D006649:Histocompatibility Antigens; D051920:NK Cell Lectin-Like Receptor Subfamily D