Promotes cell death. Successfully competes for the binding to Bcl-X(L), Bcl-2 and Bcl-W, thereby affecting the level of heterodimerization of these proteins with BAX. Can reverse the death repressor activity of Bcl-X(L), but not that of Bcl-2 (By similarity). Appears to act as a link between growth factor receptor signaling and the apoptotic pathways. Forms heterodimers with the anti-apoptotic proteins, Bcl-X(L), Bcl-2 and Bcl-W. Also binds protein S100A10 (By similarity). The Ser-75/Ser-99 phosphorylated form binds 14-3-3 proteins (By similarity). Interacts with AKT1 and PIM3. Interacts (via BH3 domain) with NOL3 (via CARD domain); preventing the association of BAD with BCL2 (By similarity). Interacts with HIF3A (via C-terminus domain); the interaction reduces the binding between BAD and BAX (By similarity). Interacts with GIMAP3/IAN4 and GIMAP5/IAN5 (PubMed:16509771). Colocalizes with HIF3A in the cytoplasm (By similarity). Upon phosphorylation, locates to the cytoplasm. Expressed in a wide variety of tissues. Intact BH3 motif is required by BIK, BID, BAK, BAD and BAX for their pro-apoptotic activity and for their interaction with anti-apoptotic members of the Bcl-2 family. Phosphorylated on one or more of Ser-75, Ser-99, Ser-118 and Ser-134 in response to survival stimuli, which blocks its pro-apoptotic activity. Phosphorylation on Ser-99 or Ser-75 promotes heterodimerization with 14-3-3 proteins. This interaction then facilitates the phosphorylation at Ser-118, a site within the BH3 motif, leading to the release of Bcl-X(L) and the promotion of cell survival. Ser-99 is the major site of AKT/PKB phosphorylation, Ser-118 the major site of protein kinase A (CAPK) phosphorylation. Phosphorylation at Ser-99 by PKB/AKT1 is almost completely blocked by the apoptotic C-terminus cleavage product of PKN2 generated by caspases-3 activity during apoptosis. Methylation at Arg-94 and Arg-96 by PRMT1 inhibits Akt-mediated phosphorylation at Ser-99. Belongs to the Bcl-2 family. The protein name 'Bcl2 antagonist of cell death' may be misleading. The protein antagonises Bcl2-mediated repression of cell death, hence it promotes apoptosis. Bcl 2-associated death promoter entry