Sodium-dependent phosphate transporter 2 is a protein that in humans is encoded by the SLC20A2gene.[5][6][7]
Genomics
This gene is found on the short arm of chromosome 8 (8p12-p11) on the minus (Crick) strand. It is 123,077 bases in length. The encoded protein has 652 amino acids and the predicted molecular weight of the protein is 70.392 kiloDaltons.
Function
The protein acts as a homodimer and is involved in phosphate transport by absorbing phosphate from interstitial fluid for normal cellular functions such as cellular metabolism, signal transduction, and nucleic acid and lipid synthesis.
Clinical significance
Mutations in the SLC20A2 gene are associated with idiopathic basal ganglia calcification (Fahr's syndrome). This association suggests that familial idiopathic basal ganglia calcification is caused by changes in phosphate homeostasis, since this gene encodes for PIT-2, an inorganic phosphate transporter.[8]
^Wang C, Li Y, Shi L, Ren J, Patti M, Wang T, de Oliveira JR, Sobrido MJ, Quintáns B, Baquero M, Cui X, Zhang XY, Wang L, Xu H, Wang J, Yao J, Dai X, Liu J, Zhang L, Ma H, Gao Y, Ma X, Feng S, Liu M, Wang QK, Forster IC, Zhang X, Liu JY (February 2012). "Mutations in SLC20A2 link familial idiopathic basal ganglia calcification with phosphate homeostasis". Nat Genet. 44 (3): 254–6. doi:10.1038/ng.1077. PMID22327515.
Bøttger P, Pedersen L (2005). "Evolutionary and experimental analyses of inorganic phosphate transporter PiT family reveals two related signature sequences harboring highly conserved aspartic acids critical for sodium-dependent phosphate transport function of human PiT2". FEBS J. 272 (12): 3060–74. doi:10.1111/j.1742-4658.2005.04720.x. PMID15955065.