Sodium-dependent phosphate transport protein 2A
Sodium-dependent phosphate transport protein 2A, also known as Na+-Pi cotransporter 2a, is a protein in humans that is encoded by the SLC34A1 gene. This gene encodes a member of the type II sodium-phosphate cotransporter family.Function
The sodium/phosphate cotransporter is a protein found in the proximal tubule of the nephron. It is responsible for reabsorbing approximately 80% of the phosphate that has been filtered out at the glomerulus. The transporter moves hydrogen phosphate into the cell along with 3 sodium ions. Alternatively it can move dihydrogen phosphate. PTH acts to decrease phosphate reabsorption from the renal filtrate and therefore promote its excretion into the urine. It does this by causing for endocytosis of NaPi transporters on the apical surface of the cell. With less transporter available more phosphate is lost in the urine.Clinical significance
Mutations in this gene are associated with hypophosphatemia nephrolithiasis/osteoporosis 1.
