This is a family of sodium/calcium exchanger integral membrane proteins. This family covers the integral membrane regions of the proteins. Sodium/calcium exchangers regulate intracellular Ca2+ concentrations in many cells; cardiac myocytes, epithelial cells, neurons retinal rod photoreceptors and smooth muscle cells [2]. Ca2+ is moved into or out of the cytosol depending on Na+ concentration [2]. In humans and rats there are 3 isoforms; NCX1 NCX2 and NCX3 [1] see Swiss:Q01728, Swiss:P48768 and Swiss:P70549 respectively.

1: Cloning of a third mammalian Na+-Ca2+ exchanger, NCX3. Nicoll DA, Quednau BD, Qui Z, Xia YR, Lusis AJ, Philipson KD; J Biol Chem 1996;271:24914-24921. PMID:8798769

2: Molecular cloning and functional expression of the cardiac sarcolemmal Na(+)-Ca2+ exchanger. Nicoll DA, Longoni S, Philipson KD; Science 1990;250:562-565. PMID:1700476