FIGURE 4.

SUMO E3 activity is not required for inhibition of TLR and RLR signaling by PIASy. A, HA-tagged WT PIASy or PIASy/C335F was transfected to 293T cells together with T7-tagged WT SUMO1, SUMO1/GA, or SUMO2. Whole cell extracts were subjected to Western blot (WB) analysis with the indicated antibodies. B, 293T cells were transfected with VISA (left) or TRIF (right), IFNβ promoter reporter, and increasing amounts of WT PIASy, PIASy/C335F, or cyan fluorescent protein (CFP). Luciferase activities were quantified by normalizing with Renilla luciferase activities.