Structural highlights
Function
[GB_HHV1K] 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).[1]
Publication Abstract from PubMed
Paired Ig-like type 2 receptor alpha (PILRalpha) recognizes a wide range of O-glycosylated mucin and related proteins to regulate broad immune responses. However, the molecular characteristics of these recognitions are largely unknown. Here we show that sialylated O-linked sugar T antigen (sTn) and its attached peptide region are both required for ligand recognition by PILRalpha. Furthermore, we determined the crystal structures of PILRalpha and its complex with an sTn and its attached peptide region. The structures show that PILRalpha exhibits large conformational change to recognize simultaneously both the sTn O-glycan and the compact peptide structure constrained by proline residues. Binding and functional assays support this binding mode. These findings provide significant insight into the binding motif and molecular mechanism (which is distinct from sugar-recognition receptors) by which O-glycosylated mucin proteins with sTn modifications are recognized in the immune system as well as during viral entry.
Structural basis for simultaneous recognition of an O-glycan and its attached peptide of mucin family by immune receptor PILRalpha.,Kuroki K, Wang J, Ose T, Yamaguchi M, Tabata S, Maita N, Nakamura S, Kajikawa M, Kogure A, Satoh T, Arase H, Maenaka K Proc Natl Acad Sci U S A. 2014 Jun 17;111(24):8877-82. doi:, 10.1073/pnas.1324105111. Epub 2014 Jun 2. PMID:24889612[2]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Subramanian RP, Geraghty RJ. Herpes simplex virus type 1 mediates fusion through a hemifusion intermediate by sequential activity of glycoproteins D, H, L, and B. Proc Natl Acad Sci U S A. 2007 Feb 20;104(8):2903-8. Epub 2007 Feb 13. PMID:17299053 doi:10.1073/pnas.0608374104
- ↑ Kuroki K, Wang J, Ose T, Yamaguchi M, Tabata S, Maita N, Nakamura S, Kajikawa M, Kogure A, Satoh T, Arase H, Maenaka K. Structural basis for simultaneous recognition of an O-glycan and its attached peptide of mucin family by immune receptor PILRalpha. Proc Natl Acad Sci U S A. 2014 Jun 17;111(24):8877-82. doi:, 10.1073/pnas.1324105111. Epub 2014 Jun 2. PMID:24889612 doi:http://dx.doi.org/10.1073/pnas.1324105111