PDBsum entry 6f9c

Virus

PDB id: 6f9c

Contents

Protein chains

(+ 0 more) 301 a.a.

(+ 0 more) 431 a.a.

PDB id:

6f9c

Name:

Virus

Title:

Model of the rift valley fever virus glycoprotein hexamer type 1

Structure:

Glycoprotein. Chain: a, c, e, g, i, k. Engineered: yes. Glycoprotein. Chain: b, d, f, h, j, l. Engineered: yes

Source:

Rift valley fever virus. Rvfv. Organism_taxid: 11588. Expressed in: homo sapiens. Expression_system_taxid: 9606. Expression_system_taxid: 9606

Authors:

S.Halldorsson,T.A.Bowden,J.T.Huiskonen

Key ref:

S.Halldorsson et al. (2018). Shielding and activation of a viral membrane fusion protein. Nat Commun, 9, 349. PubMed id: 29367607

Date:

14-Dec-17 Release date: 31-Jan-18

Protein chains

P21401  (GP_RVFVZ) -  Envelopment polyprotein from Rift valley fever virus (strain ZH-548 M12)

Seq: 1197 a.a.

Struc: 301 a.a.*

Protein chains

P21401  (GP_RVFVZ) -  Envelopment polyprotein from Rift valley fever virus (strain ZH-548 M12)

Seq: 1197 a.a.

Struc: 431 a.a.*

* PDB and UniProt seqs differ at 6 residue positions (black crosses)

Nat Commun 9:349 (2018)

PubMed id: 29367607

Shielding and activation of a viral membrane fusion protein.

S.Halldorsson, S.Li, M.Li, K.Harlos, T.A.Bowden, J.T.Huiskonen.

ABSTRACT

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.