Structures of vesicular stomatitis virus glycoprotein: membrane fusion revisited.
Glycoprotein G of the vesicular stomatitis virus (VSV) is involved in receptor recognition at the host cell surface and then, after endocytosis of the virion, triggers membrane fusion via a low pH-induced structural rearrangement. G is an atypical fusion protein, as there is a pH-dependent equilibrium between its pre- and post-fusion conformations. The atomic structures of these two conformations reveal that it is homologous to glycoprotein gB of herpesviruses and that it combines features of the previously characterized class I and class II fusion proteins. Comparison of the structures of G pre- and postfusion states shows a dramatic reorganization of the molecule that is reminiscent of that of paramyxovirus fusion protein F. It also allows identification of conserved key residues that constitute pH-sensitive molecular switches. Besides the similarities with other viral fusion machineries, the fusion properties and structures of G also reveal some striking particularities that invite us to reconsider a few dogmas concerning fusion proteins.
Roche
S
S
CNRS, UMR2472, INRA, UMR1157, IFR 115, Virologie Moléculaire et Structurale, Gif sur Yvette, France.
Albertini
A A V
AA
Lepault
J
J
Bressanelli
S
S
Gaudin
Y
Y
D000595:Amino Acid Sequence; D006863:Hydrogen-Ion Concentration; D008561:Membrane Fusion / Q000502:physiology*; D008562:Membrane Glycoproteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009154:Mutation; D011487:Protein Conformation; D012209:Rhabdoviridae / Q000378:metabolism; D014721:Vesicular stomatitis Indiana virus / Q000378:metabolism*; D014759:Viral Envelope Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D053586:Virus Internalization
C028391:G protein, vesicular stomatitis virus; D008562:Membrane Glycoproteins; D014759:Viral Envelope Proteins