A bioinformatic search of the sequence databases identified one homologue of the MRS2 gene of yeast in a range of metazoans. The protein has a very similar sequence and predicted TM topology to the yeast protein, and the GMN motif is intact at the end of the first TM domain. The human protein, hsaMrs2p, has been localised to the mitochondrial membrane in mouse cells using a GFP fusion protein.
Very little is known about the Mg transport characteristics of the protein in mammals, but Zsurka et al. (2001) has shown that the human Mrs2p complements the mrs2 mutants in the yeast mitochondrial Mg uptake system.