Severe Acute Respiratory Syndrome Coronavirus Envelope Protein Ion Channel Activity Promotes Virus Fitness and Pathogenesis
Figure 2
Subcellular localization of rSARS-CoV-EIC− E proteins, growth kinetics and plaque size.
(A) Vero E6 cells were infected either with the mutant viruses (N15A and V25F), the parental virus (wt) or a virus lacking E gene (ΔE) at an MOI of 0.3, fixed at 24 hpi and E protein (green) and ERGIC (red) were labeled with specific antibodies. Nuclei were stained with DAPI (blue). Original magnification was 126×. Right graphic on the panel represents the percentage of colocalization between E protein and ERGIC, calculated with Leica LAS AF v2.6.0 software. (B) Vero E6 and DBT-mACE2 cells were infected at an MOI of 0.001 with mutant viruses lacking IC activity (N15A and V25F), the parental virus (wt) or a virus lacking E gene (ΔE), and viral progeny was titrated at the indicated times post-infection. Error bars represent the standard deviation of three independent experiments. (C) Plaque morphology of the parental, the mutant viruses N15A and V25F and a ΔE virus.