FIG 7.

Rad18 levels contribute to viral infectivity. Knockdown of Rad18 levels with siRNA reduces viral infectivity (A to C). (A) Extracellular genome copies. 293EBV+ cells were treated with siRNA against Rad18 and induced with BZLF1 for 48 h. DNA was extracted from supernatant fluids, and genome copies were detected with quantitative PCR (qPCR) targeting the BamHI repeat region. (B) Viral infectivity. The same supernatant fluids collected for assay of extracellular genome copy number were assayed for infectious titer on Raji cells. Infectivity was determined with flow cytometry 48 and 72 h after infection. (C) Immunoblots showing knockdown of Rad18. (D) Viral infectivity of BPLF1 knockout virus is partially restored by overexpression of Rad18. BPLF1 knockout virus was induced with Z and assayed for infectivity on Raji cells. Rad18 and BPLF1 were overexpressed as indicated. Experiments were performed in triplicate, and error bars represent the standard errors of means.