BAX, also named as BCL2L4, is a pro-apoptotic member of the Bcl-2 protein family, which playsa pivotal role in controlling cell life and death. Bax largely localizes to the cytoplasm of healthycells, butaccumulates on the outer mitochondrial membrane upon apoptosis induction (PMID:9108035). BAX can commit a cell to apoptosis by translocation from the cytosol to themitochondria and permeabilization of the outer mitochondrial membrane, which leads to therelease of cytochrome c from mitochondria (PMID: 21763611). The expression of BAX isupregulated by the tumor suppressor protein p53, and BAX has been shown to be involved inp53-mediated apoptosis.