Fig. 3.

TNF signals through TNF receptor (TNFR) 1 to induce COX-2 expression. Expression of hemagglutinin (HA)-tagged death domain deletion (ΔDD) mutant TNFR1 and wild-type (WT) TNFR1 in TNFR1^−/− MCE cells (A) and WT TNFR2 in TNFR2^−/− MCE cells (B). YAMC, TNFR1^−/− empty vector (Vec), ΔDD TNFR1, and WT TNFR1 MCE cells (C) and TNFR2^−/− Vec and WT TNFR2 MCE cells (D) were treated with TNF (100 ng/ml) or EGF (10 ng/ml) for 24 h. E: WT ImSt, TNFR1^−/−, and TNFR2^−/− cells were treated with TNF or EGF for 24 h. Cell lysates were analyzed for protein expression as described in Fig. 1 legend.