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1ydp
From Proteopedia
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1.9A crystal structure of HLA-G
Contents |
Overview
HLA-G is a nonclassical major histocompatibility complex class I (MHC-I) molecule that is primarily expressed at the fetal-maternal interface, where it is thought to play a role in protecting the fetus from the maternal immune response. HLA-G binds a limited repertoire of peptides and interacts with the inhibitory leukocyte Ig-like receptors LIR-1 and LIR-2 and possibly with certain natural killer cell receptors. To gain further insights into HLA-G function, we determined the 1.9-A structure of a monomeric HLA-G complexed to a natural endogenous peptide ligand from histone H2A (RIIPRHLQL). An extensive network of contacts between the peptide and the antigen-binding cleft reveal a constrained mode of binding reminiscent of the nonclassical HLA-E molecule, thereby providing a structural basis for the limited peptide repertoire of HLA-G. The alpha3 domain of HLA-G, a candidate binding site for the LIR-1 and -2 inhibitory receptors, is structurally distinct from the alpha3 domains of classical MHC-I molecules, providing a rationale for the observed affinity differences for these ligands. The structural data suggest a head-to-tail mode of dimerization, mediated by an intermolecular disulfide bond, that is consistent with the observation of HLA-G dimers on the cell surface.
Disease
Known diseases associated with this structure: Asthma, susceptibility to OMIM:[142871], Hypoproteinemia, hypercatabolic OMIM:[109700]
About this Structure
1YDP is a Protein complex structure of sequences from Homo sapiens with and as ligands. Full crystallographic information is available from OCA.
Reference
Crystal structure of HLA-G: a nonclassical MHC class I molecule expressed at the fetal-maternal interface., Clements CS, Kjer-Nielsen L, Kostenko L, Hoare HL, Dunstone MA, Moses E, Freed K, Brooks AG, Rossjohn J, McCluskey J, Proc Natl Acad Sci U S A. 2005 Mar 1;102(9):3360-5. Epub 2005 Feb 17. PMID:15718280
Page seeded by OCA on Thu Feb 21 16:04:19 2008
Categories: Homo sapiens | Protein complex | Brooks, A G. | Clements, C S. | Dunstone, M A. | Freed, K. | Hoare, H L. | Kjer-nielsen, L. | Kostenko, L. | Mccluskey, J. | Moses, E. | Rossjohn, J. | CL | CO | Immune system
