Fig. 5.

Deregulation of p53 and NF-κB in TPPII-deficient fibroblasts and T cells. (A) Defective NF-κB activation in KO fibroblasts upon addition of TNF-α as shown by nuclear NF-κB p65 DNA binding activity (in relative light units in Top) and p65 protein levels in nuclear extracts (Middle). Protein levels of Sp1 are shown as control. Strongly increased p53 protein expression in cultures of TPPII KO fibroblasts is shown in Bottom. Actin expression is shown as control. (B) Higher basal NF-κB activity in TPPII-deficient splenic T cells directly ex vivo. Data are the mean ± SD for four mice of each genotype (Top). Dysregulated NF-κB p65 activation (Middle) and p53 protein expression (Bottom) in TCR-stimulated splenic T cells are shown. In each panel, representative results of at least two independent experiments with similar results are shown.