FIG 5.

LMP1 expression correlates with endogenous KAP1 sumoylation in a CTAR3-dependent manner. (A) Denaturing immunoprecipitations (IP) were performed on BL41 EBV-negative, BL41 EBV-positive, and BL41 P3HR1 mutant-infected cells with SUMO-1-specific antibodies or IgG control antibodies. Western blot (WB) analyses were used to detect KAP1 covalently modified by SUMO-1. (B) Densitometric analysis of repeat experiments was performed. Results are shown as means ± standard deviations from experiments performed in triplicate. pos, positive; neg, negative. (C) Western blot analyses were used to detect KAP1 covalently modified by SUMO-1 in paired EBV WT- and EBV dCTAR3-transformed LCLs with SUMO-1-specific antibodies or IgG control antibodies. (D) Densitometric analysis of repeat experiments was performed. Results are shown as means ± standard deviations from experiments performed in triplicate. (E) 293 cells were transfected with GFP-KAP1 and either FLAG-LMP1, FLAG-LMP1 dCTAR3, or vector control expression constructs. At 48 h posttransfection, whole-cell lysates were collected and immunoblotting assays were performed to detect LMP1 (FLAG) and KAP1 (GFP) levels. GAPDH was used as a loading control.