May induce apoptosis through the lysosomal-mitochondrial pathway. Translocates to the lysosome initiating the permeabilization of lysosomal membrane (LMP) and resulting in the release of CTSD and CTSL to the cytoplasm. Triggers the caspase-independent apoptosis by altering mitochondrial membrane permeabilization (MMP) resulting in the release of PDCD8. Translocates to lysosome during apoptosis. Highly expressed in heart and skeletal muscle. Weakly expressed in brain, thymus, spleen, kidney, liver, small intestine, placenta and lung. PH and FYVE-type zinc finger domains are required for lysosomal location.