Inhibits TNF-induced apoptosis by mediating the TNFAIP3 anti-apoptotic activity. Degraded by caspase-3-like family proteins upon TNF-induced apoptosis. May also play a role in the pro-inflammatory cytokine IL-1 signaling cascade. Homooligomer. Interacts with TRAF6 in a IL-1-dependent manner. Interacts with TNFAIP3. Interacts with STARD13. Interacts with the HTLV-1 protein Tax-1. Expressed in all tissues tested. The C-terminal UBZ-type zinc fingers function as ubiquitin-binding domains. Phosphorylated in the C-terminal region by CHUK/IKKA leading to NF-kappa-B signaling down-regulation.