Figure 2.

Complementation ratios produced by mutant UL20p genes. Vero cells were transfected with plasmids encoding wild-type or mutant UL20 genes under the UL20 promoter and then infected with the HSV-1(KOS) UL20-null (Δ20) virus. Viral stocks were prepared at 24 hours post infection and tittered on Vero cells (see Materials & Methods). The error bars shown represent the maximum and minimum complementation ratios obtained from three independent experiments, and the bar height represents the average complementation ratio.