Solute Carrier Family 24, Member 4 (SLC24A4)

Potassium-dependent sodium/calcium exchangers, such as NCKX4, are thought to transport 1 intracellular calcium and 1 potassium ion in exchange for 4 extracellular sodium ions.The deduced 605-amino acid protein contains an N-terminal signal peptide followed by an extracellular loop with 2 glycosylation sites, 5 transmembrane segments, a large intracellular loop with several putative phosphorylation sites, and a second cluster of 5 transmembrane segments. NCKX4 shares about 60% amino acid identity with NCKX3. In addition, utilization of a second putative translation initiation codon could result in a protein lacking the N-terminal signal sequence. Northern blot analysis of several rat tissues detected an abundant 10-kb transcript in brain, aorta, lung, and thymus.