Lysosomal modulator of autophagy that plays a central role in p53/TP53-mediated apoptosis. Not involved in p73/TP73-mediated autophagy. By p53/TP53 and p73/TP73. Directly activated by p53/TP53. Significantly down-regulated in tumor cell lines by methylation-dependent transcriptional silencing. Belongs to the DRAM/TMEM150 family.