SLC20A1,2 cotransport Pi, Na+ from extracellular region to cytosol

Stable Identifier
Reaction [transition]
Homo sapiens
Type III Na+/Pi cotransport
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There are two transporters of this type; The genes SLC20A1 and SLC20A2 encode for phosphate transporters 1 and 2 (PiT1 and PiT2 respectively). They both have a broad tissue distribution and may play a general housekeeping role in phosphate transport such as absorbing phosphate from interstitial fluid and in extracellular matrix and cartilage calcification as well as in vascular calcification. These proteins were originally described as retroviral receptors for the gibbin ape leukemia virus receptor 1 (GLVR1, now called PiT1) (O'Hara et al. 1990) and GLVR2 (now called PiT2) (van Zeijl et al.1994). However, they were found to possess Na+-coupled phosphate cotransporter function (Fernandes et al. 1999). The transport is electrogenic with a stoichiometry of 2:1 (Na+:Pi).

Literature References
PubMed ID Title Journal Year
2078500 Characterization of a human gene conferring sensitivity to infection by gibbon ape leukemia virus

Klinger, HP, Dunn, KJ, Johann, SV, Sass, P, O'Hara, B, Robins, T, Rubinson, H, Blair, DG, Vitek, SM

Cell Growth Differ 1990
8302848 A human amphotropic retrovirus receptor is a second member of the gibbon ape leukemia virus receptor family

Cunningham, J, van Zeijl, M, Johann, SV, O'Hara, B, Eddy, RL, Shows, TB, Closs, E

Proc Natl Acad Sci U S A 1994
10516278 NaPO(4) cotransport type III (PiT1) expression in human embryonic kidney cells and regulation by PTH

Beliveau, R, Fernandes, I, Silve, C, Friedlander, G

Am J Physiol 1999
Catalyst Activity

sodium:phosphate symporter activity of Type III Na+/Pi cotransporters [plasma membrane]

Orthologous Events
Cross References
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