Fig. 4.

Sustained pUS28 expression suppresses lytic gene expression. THP-1-pSLIK-US28-3xF cells were treated with (+) or without (−) DOX (1 μg/mL) for 48 h to induce pUS28 expression and then infected with WT (blue) or US28Δ (green) (moi = 1.0). Cells were cultured for 7 d, during which cells were maintained under their original treatment conditions (First 7 d). At 7 dpi, cells were washed and treated with (+) or without (−) DOX (Last 7 d). Total RNA was harvested and (A) UL123, (B) UL99, (C) UL138, and (D) the ratio of UL138/UL123 expression were measured by RT-qPCR. Samples were normalized to GAPDH and assessed in triplicate. Errors bars indicate SD and significance calculated using one-way ANOVA and Dunnett’s post hoc analysis; *P < 0.05, ***P < 0.001.