Distribution of surface glycoproteins on influenza A virus determined by electron cryotomography.
We use electron cryotomography to reconstruct virions of two influenza A H3N2 virus strains. The maps reveal the structure of the viral envelope containing hemagglutinin (HA) and neuraminidase (NA) glycoproteins and the virus interior containing a matrix layer and an assembly of ribonucleoprotein particles (RNPs) that package the genome. We build a structural model for the viral surface by locating copies of the X-ray structure of the HA ectodomain into density peaks on the virus surface. We calculate inter-glycoprotein distances and the fractional volume occupied by glycoproteins. The models suggest that for typical HA densities on virus, Fabs can bind to epitopes on the HA stem domain. The models also show how membrane curvature may influence the number of glycoproteins that can simultaneously interact with a target surface of receptors.
Division of Physical Biochemistry, MRC National Institute for Medical Research, The Ridgeway, Mill Hill, London, NW7 1AA, United Kingdom.
Sebastian
S
Wasilewski
Lesley J
LJ
Calder
Tim
T
Grant
Peter B
PB
Rosenthal
D020285:Cryoelectron Microscopy; D055032:Electron Microscope Tomography; D021621:Imaging, Three-Dimensional; D053121:Influenza A Virus, H2N2 Subtype / Q000737:chemistry* / Q000648:ultrastructure; D008562:Membrane Glycoproteins / Q000032:analysis*; D008958:Models, Molecular; D014764:Viral Proteins / Q000032:analysis*
D008562:Membrane Glycoproteins; D014764:Viral Proteins