FIG 5.

Suppression of PPP6C inhibits KSHV lytic reactivation due to an increased innate immune response. iSLK.219 cells were transfected with NS siRNA or PPP6C siRNA for 48 h and then treated with doxycycline (Dox; 1 μg/ml). (A) GFP- and RFP-positive cells were imaged at 0, 48, and 72 h after Dox treatment, and a representative image of each sample is shown. (B) GFP and RFP fluorescence intensities were measured by a Clariostar plate reader, and the RFP/GFP ratio was calculated at the indicated time points. (C) KSHV genome copy numbers in the supernatants were measured by real-time PCR. (D) Relative KSHV genome copy numbers in the cells were measured by real-time PCR and normalized to β-actin. (E) Cell lysates were collected at the indicated time points, and immunoblots were performed with the indicated antibodies. (F) IFN-β mRNA fold induction was measured by real-time PCR and normalized to β-actin mRNA. (G) Cell lysates were collected at the indicated time points, and immunoblots were performed with the indicated antibodies. (H and I) EA.hy926 cells were transfected with NS or PPP6C siRNA for 72 h and then infected with KSHV for the indicated times. IFN-β mRNA fold induction was measured by real-time PCR (H), and cell lysates were immunoblotted with the indicated antibodies (I). The data shown are representative of three independent experiments. Data in panels B, C, D, F, and H are presented as mean + SD. *, P < 0.05 by Student's t test. 6C, PPP6C.