FIGURE 3.

RSK is required for eIF4B and rpS6 phosphorylation during KSHV lytic replication. A, depletion of RSK and ERK expression by siRNAs decreases eIF4B and rpS6 phosphorylation. RSK1/2-, ERK-, and luciferase (Luc) siRNA-transduced BCBL1 cells were induced with TPA (17, 33). Cells were collected at different times, and cell lysates were analyzed by Western blot with antibodies as indicated. B, inhibition of RSK activity blocks eIF4B and rpS6 phosphorylation. BCBL1 cells were induced with TPA in the absence and presence of increasing concentrations of RSK inhibitor BI-D1870 for 48 h. Whole-cell lysates were then prepared and analyzed by Western blot with antibodies as indicated. LANA, latency-associated nuclear antigen.