Non-selective channel that modulates the membrane potential under normal conditions and oxidative stress, and is involved in mitochondrial homeostasis (By similarity). Involved in mitochondrial deoxynucleoside triphosphates (dNTP) pool homeostasis and mitochondrial DNA (mtDNA) maintenance (PubMed:26760297). May be involved in the regulation of reactive oxygen species metabolism and the control of oxidative phosphorylation (Probable). High levels in heart, kidney, and brain, intermediate levels in testis, and low levels in liver and spleen. Mice lack expression of this protein resulting in the development of adult onset nephrotic syndrome and chronic renal failure. They also develop severe morphological degeneration of the inner ear. In the inner ear, mice lacking Mpv17 display degenerative changes of the cochlear structures already at the age of 2 months. The degenerative changes are patchy arranged throughout the entire length of the cochlea and involved the organ of Corti as well as the stria vascularis epithelia with alterations of the basement membrane of the capillaries. Belongs to the peroxisomal membrane protein PXMP2/4 family. Was initially thought to be a peroxisomal protein (PubMed:7957077). However, it was later shown in human that it is a mitochondrial protein (PubMed:16582907 and PubMed:16582910).