1t0m | pdb_00001t0m
Conformational switch in polymorphic H-2K molecules containing an HSV peptide
Structural highlights
Function[HA1B_MOUSE] Involved in the presentation of foreign antigens to the immune system. [GB_HHV1F] Envelope glycoprotein that forms spikes at the surface of virion envelope. Essential for the initial attachment to heparan sulfate moities of the host cell surface proteoglycans. Involved in fusion of viral and cellular membranes leading to virus entry into the host cell. Following initial binding of gD to one of its receptors, membrane fusion is mediated by the fusion machinery composed at least of gB and the heterodimer gH/gL. May also be involved in the fusion between the virion envelope and the outer nuclear membrane during virion egress. Also plays a role, together with gK, in virus-induced cell-to-cell fusion (syncytia formation) (By similarity).[1] [B2MG_MOUSE] Component of the class I major histocompatibility complex (MHC). Involved in the presentation of peptide antigens to the immune system. Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedPolymorphism within the MHC not only affects peptide specificity but also has a critical influence on the T cell repertoire; for example, the CD8 T cell response toward an immunodominant HSV glycoprotein B peptide is more diverse and of higher avidity in H-2(bm8) compared with H-2(b) mice. We have examined the basis for the selection of these distinct antiviral T cell repertoires by comparing the high-resolution structures of K(b) and K(bm8), in complex with cognate peptide Ag. Although K(b) and K(bm8) differ by four residues within the Ag-binding cleft, the most striking difference in the two structures was the disparate conformation adopted by the shared residue, Arg(62). The altered dynamics of Arg(62), coupled with a small rigid-body movement in the alpha(1) helix encompassing this residue, correlated with biased Valpha usage in the B6 mice. Moreover, an analysis of all known TCR/MHC complexes reveals that Arg(62) invariably interacts with the TCR CDR1alpha loop. Accordingly, Arg(62) appears to function as a conformational switch that may govern T cell selection and protective immunity. The structure of H-2K(b) and K(bm8) complexed to a herpes simplex virus determinant: evidence for a conformational switch that governs T cell repertoire selection and viral resistance.,Webb AI, Borg NA, Dunstone MA, Kjer-Nielsen L, Beddoe T, McCluskey J, Carbone FR, Bottomley SP, Aguilar MI, Purcell AW, Rossjohn J J Immunol. 2004 Jul 1;173(1):402-9. PMID:15210799[2] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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