6f9e

Model of the Rift Valley fever virus glycoprotein hexamer type 3Model of the Rift Valley fever virus glycoprotein hexamer type 3

6f9e, resolution 13.30Å Show:Asymmetric Unit Biological Assembly Structural highlights 6f9e is a 12 chain structure with sequence from Rvfv. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Experimental data: Check Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Publication Abstract from PubMed Entry of enveloped viruses relies on insertion of hydrophobic residues of the viral fusion protein into the host cell membrane. However, the intermediate conformations during fusion remain unknown. Here, we address the fusion mechanism of Rift Valley fever virus. We determine the crystal structure of the Gn glycoprotein and fit it with the Gc fusion protein into cryo-electron microscopy reconstructions of the virion. Our analysis reveals how the Gn shields the hydrophobic fusion loops of the Gc, preventing premature fusion. Electron cryotomography of virions interacting with membranes under acidic conditions reveals how the fusogenic Gc is activated upon removal of the Gn shield. Repositioning of the Gn allows extension of Gc and insertion of fusion loops in the outer leaflet of the target membrane. These data show early structural transitions that enveloped viruses undergo during host cell entry and indicate that analogous shielding mechanisms are utilized across diverse virus families. Shielding and activation of a viral membrane fusion protein.,Halldorsson S, Li S, Li M, Harlos K, Bowden TA, Huiskonen JT Nat Commun. 2018 Jan 24;9(1):349. doi: 10.1038/s41467-017-02789-2. PMID:29367607 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.