Figure 2

TNF receptor (TNFR) pathway of signaling. Two complex model is shown. Upon ligation with TNF-α (with in 10–20 min), TNFR I undergo trimerization and recruits various adapter molecules resulting in the activation of NF-κB, which induces several anti-apoptotic genes (Complex I formation) and survival signal. This is followed by (more than 2–3 hours) by an endocytosis of receptor complex resulting in the dissociation of certain adapter proteins (TRAF-2, RIP) and recruitment of fas – associated death domain (FADD) and procasepase-8 to form death-inducing signaling complex (DISC). In the DISC, caspase-8 is activated and released into the cytoplasm where it activates effector caspases to induce apoptosis.