FIG. 3.

Cellular distribution of IκBα is independent of the p50, p52, p65 (RelA), and c-Rel proteins. WT^+/+ (A), p50^−/− (B), p65^−/− (C), p50/p52^−/− (D), and p50/p65^−/− (E) mouse 3T3 fibroblasts or c-Rel/p65^−/− primary MEF (F) were transfected with CMV-derived expression vectors coding for wild-type MAD3. The cellular localization of the ectopically expressed MAD3 protein was determined by indirect immunofluorescence with anti-MAD3 serum. The results shown are representative of at least 100 cells that were positive for expression of the wild-type MAD3 protein (see Table 2 for quantitation).