Acts as a Mg(2+) transporter. Can also transport other divalent cations such as Fe(2+), Sr(2+), Ba(2+), Mn(2+) and Co(2+) but to a much less extent than Mg(2+) (By similarity). Homodimer. Recruited to the cell membrane in response to low extracellular magnesium. Widely expressed with highest levels in neuronal tissues. The disease is caused by variants affecting the gene represented in this entry. Belongs to the NIPA family. Contaminating sequence. Sequence of unknown origin in the N-terminal part.