(f) Lysates of 293ET cells were immunoprecipitated using the indicated antibodies or an isotype control. Precipitates were blotted for the presence of TBK1 and NDP52. Fusion proteins used in Figure 2 are further characterized in Supplementary Figure 1. Data in panels c-f are representative of at least two independent experiments. Ub, ubiquitin; PCNA, proliferating cell nuclear antigen. 