May be a signaling adapter molecule involved in p75NTR-mediated apoptosis induced by NGF. Plays a role in zinc-triggered neuronal death. Self-associates (PubMed:11830582). Binds to the DEATH domain of p75NTR/NGFR (PubMed:11830582). Interacts with 14-3-3 epsilon (YWHAE) (PubMed:11278287). Interacts with DIABLO/SMAC (PubMed:15178455). Shuttles between the cytoplasm and the nucleus. Associates with replicating mitochondria. Widely expressed. The nuclear export signal is required for export from the nucleus and the interactions with itself and p75NTR/NGFR. Ubiquitinated (Probable). Degraded by the proteasome. Binds transition metals. Belongs to the BEX family. Extended C-terminus.