Specific Residues in the 2009 H1N1 Swine-Origin Influenza Matrix Protein Influence Virion Morphology and Efficiency of Viral Spread In Vitro
Figure 4
Substitutions at positions 30, 207 and 209 in the ACal-04/09 M1 protein resulted in filament formation in infected cells.
A549 cells were infected with ACal-04/09 viruses containing single or multiple substitutions at positions 30, 142, 207, and 209 in the M1 protein as indicated. Cells were fixed and processed for visualization of viral surface proteins 18 h by IF microscopy as described for Fig. 1.