Deficiency in TTP results in overexpression of TF mRNA due to mRNA stabilization. (A) WT and Ttp^−/− murine BMDM were stimulated with LPS (1 µg/mL) for the durations shown. TF mRNA levels were then determined at each time point and normalized to levels in unstimulated WT macrophages (n = 3 experiments). (B) WT and Ttp^−/− BMDM were stimulated with LPS (1 µg/mL) for the durations shown, after which western blotting was used for cell lysates. The blots shown are representative of 5 experiments and are all from the same gel and are processed simultaneously, with WT and Ttp^−/− lanes separated for clarity. (C) WT and Ttp^−/− macrophages were stimulated with LPS (1 µg/mL) for 2 hours, after which actinomycin D (5 µg/mL) was added and TF mRNA decay was assessed. All data are expressed as mean ± SEM and analyzed using a 2-tailed Student t test. NS, not significant. *P < .05; ***P < .001. ActD, actinomycin D; Rel, relative.