SLC23A1,2 cotransports AscH-, 2Na+ from extracellular region to cytosol

Stable Identifier
Reaction [transition]
Homo sapiens
Ascorbate transport across the plasma membrane, ascorbate [extracellular] + 2 Na+ [extracellular] => ascorbate [cytosol] + 2 Na+ [cytosol]
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The plasma membrane-associated transport proteins SVCT1 and SVCT2 (encoded by SLC23A1 and SLC23A2 respectively) are each capable of mediating the uptake of one molecule of ascorbate (AscH-) and two sodium ions from the extracellular space to the cytosol (Daruwala et al. 1999, Rajan et al. 1999, Wang et al. 1999). In the body SVCT2 is expressed in most tissues, while SVCT1 is largely confined to epithelial cells (Liang et al. 2001). SVCT2 may mediate fetal uptake of ascorbate from the maternal circulation (Rajan et al. 1999). The transporters responsible for its uptake from the small intestine and for its release from enterocytes into the circulation have not been identified, although both SVCT1 and 2 are expressed in intestinal cells.

Literature References
PubMed ID Title Journal Year
10556483 Human Na+-dependent vitamin C transporter 1 (hSVCT1): primary structure, functional characteristics and evidence for a non-functional splice variant

Dutta, B, Wang, H, Leibach, FH, Ganapathy, V, Huang, W, Devoe, LD, Prasad, PD

Biochim Biophys Acta 1999
10471399 Human placental sodium-dependent vitamin C transporter (SVCT2): molecular cloning and transport function

Dutta, B, Leibach, FH, Ganapathy, V, Huang, W, Devoe, LD, Rajan, DP, Prasad, PD

Biochem Biophys Res Commun 1999
10556521 Cloning and functional characterization of the human sodium-dependent vitamin C transporters hSVCT1 and hSVCT2

Rumsey, SC, Daruwala, R, Koh, WS, Song, J, Levine, M

FEBS Lett 1999
11396616 Vitamin C transport systems of mammalian cells

Liang, W-J, Johnson, D, Jarvis, SM

Mol Membr Biol 2001
Catalyst Activity

L-ascorbic acid transmembrane transporter activity of SLC23A1,2 [plasma membrane]

Orthologous Events
Cross References
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