Regulator of mitochondrial apoptosis and G1 cell cycle. Regulates the level of PP2A regulatory subunit B and PP2A phosphatase activity (By similarity). Interacts with LMO2, possibly leading to regulate the transcriptional activity of a DNA-binding complex containing LMO2 (By similarity). Interacts with OMP. Primarily localized to neuronal cells within several regions of the brain, including the olfactory epithelium, bulb, peri/paraventricular nuclei, suprachiasmatic nucleus, arcuate nucleus, median eminence, lateral hypothalamic area, thalamus, hippocampus and cerebellum (at protein level). Belongs to the BEX family.