The influence of ectopic expression of Sp1, Sp2, Sp3 and Sp4 on IE62 mediated transactivation of model promoters. A) Schematic of the model promoters and sequences of the consensus TATA element and the Sp1 site in the downstream region of VZV oriS. Results of triplicate transient transfection assays determining the effect of Sp family members’ overexpression on IE62 mediated transactivation are shown for B) the TA-Luc model promoter and C) the Sp1-TA-Luc model promoter. Luciferase activities in the absence of IE62 and ectopic expression of Sp family members were normalized to one. Promoter activities in the presence of IE62 and ectopic expression of Sp1, Sp2, Sp3, Sp4 or both are reported as induction (n-fold) of the luciferase activity over the basal activity. Statistical significance was determined by a one-way ANOVA analysis of variance followed by Tukey’s post hoc test. Error bars indicate standard error.