The MMgT gene family is comprised of two members: MMgT1 (membrane Mg2+ transporter 1) and MMgT2 (membrane Mg2+ transporter 2). Both proteins mediate Mg2+ uptake when expressed in Xenopus laevis oocytes. An increase in MMgT1 and MMgT2 transcripts is detected when there are low levels of Mg2+. There are two predicted transmembrane domains suggesting that the protein can form functional oligomers. It has been suggested that it may form homo- and, perhaps, heterooligomeric units
