Na(+)/Mg(2+) ion exchanger that acts as a predominant Mg(2+) efflux system at the plasma membrane ( , ). Transporter activity is driven by the inwardly directed electrochemical gradient for Na(+) ions, thus directly depends on the extracellular Na(+) ion concentration set by Na(+)/K(+) pump (, ). Generates circadian cellular Mg(2+) fluxes that feed back to regulate clock-controlled gene expression and metabolism and facilitate higher energetic demands during the day . Has a role in regulating the activity of ATP-dependent enzymes, including those operating in Krebs cycle and the electron transport chain (By similarity).
Subcellular locations: Cell membrane, Basolateral cell membrane
Highest expression levels in heart and testis, slightly less in skeletal muscles, prostate, adrenal gland and thyroid, and weakest in the hematopoietic tissues bones marrow, lymph node, thymus and spleen. In the kidney, it is expressed in the distal convoluted tubules, macula densa, and thick ascending limb tubular segments of the nephrons .