Crystal structure and ligand binding properties of the D1D2 region of the inhibitory receptor LIR-1 (ILT2).
LIR-1 is an inhibitory receptor that recognizes class I MHC molecules and the human cytomegalovirus class I homolog UL18. Here, we report the 2.1 A resolution crystal structure of the ligand binding portion of LIR-1 (domains 1 and 2 [D1D2]) and localize the binding region for UL18. LIR-1 D1D2 is composed of two immunoglobulin-like domains arranged at an acute angle to form a bent structure resembling the structures of natural killer inhibitory receptors (KIRs). The LIR-1 binding site comprises a portion of D1 distant from the interdomain hinge region that constitutes the KIR binding site, consistent with differences in LIR-1 and KIR recognition properties and functions.
Chapman
T L
TL
Division of Biology 156-29, California Institute of Technology, Pasadena, CA 91125, USA.
Heikema
A P
AP
West
A P
AP
Bjorkman
P J
PJ
D000595:Amino Acid Sequence; D015703:Antigens, CD; D006023:Glycoproteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D006801:Humans; D000075362:Leukocyte Immunoglobulin-like Receptor B1; D008024:Ligands; D008969:Molecular Sequence Data; D011485:Protein Binding; D011487:Protein Conformation; D011971:Receptors, Immunologic / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D011991:Receptors, Virus / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment
D015703:Antigens, CD; D006023:Glycoproteins; C105299:LILRB1 protein, human; D000075362:Leukocyte Immunoglobulin-like Receptor B1; D008024:Ligands; D011971:Receptors, Immunologic; D011991:Receptors, Virus