The CorA transport system is the primary Mg2+ influx system of Salmonella typhimurium and Escherichia coli. CorA is virtually ubiquitous in the Bacteria and Archaea. There are also eukaryotic relatives of this protein. The family includes the MRS2 protein from yeast that is thought to be an RNA splicing protein. However its membership of this family suggests that its effect on splicing is due to altered magnesium levels in the cell.