title: Crystal structure of HLA-A2 bound to LIR-1, a host and viral major histocompatibility complex receptor.
abstract: Leukocyte immunoglobulin-like receptor 1 (LIR-1), an inhibitory receptor expressed on monocytes, dendritic cells and lymphocytes, regulates cellular function by binding a broad range of classical and nonclassical major histocompatibility complex (MHC) class I molecules, and the human cytomegalovirus MHC class I homolog UL18. Here we describe the 3.4-A crystal structure of a complex between the LIR-1 D1D2 domains and the MHC class I molecule HLA-A2. LIR-1 contacts the mostly conserved beta(2)-microglobulin and alpha3 domains of HLA-A2. The LIR-1 binding site comprises residues at the interdomain hinge, and a patch at the D1 tip. The structure shows how LIR-1 recognizes UL18 and diverse MHC class I molecules, and indicates that a similar mode of MHC class I recognition is used by other LIR family members.
authors.affiliation: Division of Biology 114-96, California Institute of Technology, Pasadena, California 91125, USA.
authors.forename: Benjamin E
authors.initials: BE
authors.lastname: Willcox
authors.forename: Leonard M
authors.initials: LM
authors.lastname: Thomas
authors.forename: Pamela J
authors.initials: PJ
authors.lastname: Bjorkman
mesh_terms: D000595:Amino Acid Sequence; D015703:Antigens, CD / Q000737:chemistry*; D001665:Binding Sites; D018360:Crystallography, X-Ray; D015789:HLA-A2 Antigen / Q000737:chemistry*; D006801:Humans; D000075362:Leukocyte Immunoglobulin-like Receptor B1; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011971:Receptors, Immunologic / Q000737:chemistry*; D016415:Sequence Alignment
chemical_list: D015703:Antigens, CD; D015789:HLA-A2 Antigen; C105299:LILRB1 protein, human; D000075362:Leukocyte Immunoglobulin-like Receptor B1; D011971:Receptors, Immunologic