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
Glycoprotein B (gB) is a key component of the complex herpesvirus fusion machinery. We studied membrane interaction of two gB ectodomain forms and present an electron cryotomography structure of the gB-bilayer complex. The two forms differed in presence or absence of the membrane proximal region (MPR) but showed an overall similar trimeric shape. The presence of the MPR impeded interaction with liposomes. In contrast, the MPR-lacking form interacted efficiently with liposomes. Lateral interaction resulted in coat formation on the membranes. The structure revealed that interaction of gB with membranes was mediated by the fusion loops and limited to the outer membrane leaflet. The observed intrinsic propensity of gB to cluster on membranes indicates an additional role of gB in driving the fusion process forward beyond the transient fusion pore opening and subsequently leading to fusion pore expansion.
The Structure of Herpesvirus Fusion Glycoprotein B-Bilayer Complex Reveals the Protein-Membrane and Lateral Protein-Protein Interaction.,Maurer UE, Zeev-Ben-Mordehai T, Pandurangan AP, Cairns TM, Hannah BP, Whitbeck JC, Eisenberg RJ, Cohen GH, Topf M, Huiskonen JT, Grunewald K Structure. 2013 Jul 9. pii: S0969-2126(13)00205-0. doi:, 10.1016/j.str.2013.05.018. PMID:23850455[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
- ↑ Maurer UE, Zeev-Ben-Mordehai T, Pandurangan AP, Cairns TM, Hannah BP, Whitbeck JC, Eisenberg RJ, Cohen GH, Topf M, Huiskonen JT, Grunewald K. The Structure of Herpesvirus Fusion Glycoprotein B-Bilayer Complex Reveals the Protein-Membrane and Lateral Protein-Protein Interaction. Structure. 2013 Jul 9. pii: S0969-2126(13)00205-0. doi:, 10.1016/j.str.2013.05.018. PMID:23850455 doi:10.1016/j.str.2013.05.018
