Electrogenic Na+/Pi cotransport Electroneutral Na+/Pi cotransport PathwayStep4881 PathwayStep4882 Type II Na+/Pi cotransporters Authored: Jassal, B, 2009-06-23 Edited: Jassal, B, 2009-06-23 Pubmed12750889 Reactome Database ID Release 43427589 Reactome, http://www.reactome.org ReactomeREACT_19411 Reviewed: He, L, 2009-08-24 The SLC34 family of type II Na+/Pi cotransporters consist of three members; NaPi-IIa (SLC34A1), NaPi-IIb (SLC34A2) and NaPi-IIc (SLC34A3) (Murer H et al, 2004). They are expressed mainly in the kidney and small intestine, located at the apical sites of epithelial cells although other areas of the body express them to a lesser extent. NaPi-IIa and b cotransports divalent Pi (HPO4[2-]) with three Na+ ions (electrogenic transport) whereas NaPi-IIc cotransports divalent Pi with two Na+ ions (electroneutral transport).