Choline/H+ antiporter, mainly in mitochodria. Also acts as a low-affinity ethanolamine/H+ antiporter, regulating the supply of extracellular ethanolamine (Etn) for the CDP-Etn pathway, redistribute intracellular Etn and balance the CDP-Cho and CDP-Etn arms of the Kennedy pathway.
Subcellular locations: Cell membrane, Mitochondrion outer membrane
Mainly expressed in mitochondria.