Tax ubiquityaltion and SUMOylation control NEMO targeting into distinct subcellular compartments. HeLa cells were cotransfected with HA-SUMO1 and Tax, empty vector (control), or the Tax mutants K4-8R, K4-8R-Ub, K4-8R-SUMO1, K6-8R, K6-8R-Ub, or K6-8R-SUMO1, and stained by triple immunofluorescence with anti-Tax (blue), anti-HA (green), and anti-NEMO (IKK-γ) antibodies (red). Cells were examined by confocal microscopy. Scale bar, 10 μm. The percentage of cells displaying Tax or NEMO localization into nuclear bodies (NBs) and/or centrosome (C) are indicated.