FIG 3.

gE is not universally required for the Syn phenotype. (A) Vero cells were infected with gE deletion viruses with or without syn mutations. Cell lysates were harvested 18 to 20 hpi, and immunoblots were probed for expression of VP5, gE, and gI. (B) Vero cells were infected with gE-null/gKsyn variants at a low MOI. At 48 hpi, the cell were fixed and stained with DAPI and an antibody against VP5. Corresponding bright-field and fluorescent images were taken for each variant. (C) For each of the indicated mutants, the areas of 30 individual syncytia were measured at either 36 hpi (gKsyn parents) or 42 hpi (mutants lacking gE). The reduced average areas of the mutants relative to their gKsyn parent are plotted. ****, P < 0.0001, Student's t test. Additionally, each site of infection was scored as syncytial, mixed, or lytic (as defined in the text), with the linear distribution of these phenotypes shown graphically.