Sodium-dependent phosphate transport protein 4 (SLC17A3)

Sodium-dependent phosphate transport protein 4 (SLC17A3, also called NPT4) is a voltage-driven organic anion efflux transporter localized primarily on the apical side of renal proximal tubule cells[1][2][7]. It mediates the excretion of endogenous metabolites such as urate and various organic anions (including some drugs and toxins) from the blood into the urine, thus playing a crucial role in regulating serum uric acid levels and contributing to the elimination of xenobiotics[1][2][5][7]. SLC17A3 is functionally coupled with basolateral organic anion transporters OAT1 and OAT3, which import substrates into tubular cells for subsequent efflux by SLC17A3[2][6][7]. Polymorphisms in SLC17A3 are associated with differences in serum uric acid, hypertension, gout, and renal stone risk. Clinically relevant drug interactions, particularly with diuretics, can impair urate excretion and provoke hyperuricemia and gout[2][6][7].

Other names

NPT4Na(+)/Pi cotransporter 4Sodium/phosphate cotransporter 4Solute carrier family 17 member 3GOUT4UAQTL4

Drugs (e.g., loop diuretics) can inhibit SLC17A3-mediated urate and drug efflux, precipitating hyperuricemia via decreased renal urate excretion[2][6]. Substrates are transported in a voltage-driven process across the apical membrane of renal tubule cells.