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J Clin Invest
1994 Jan 01;931:397-404. doi: 10.1172/JCI116972.
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The human kidney low affinity Na+/glucose cotransporter SGLT2. Delineation of the major renal reabsorptive mechanism for D-glucose.
Kanai Y, Lee WS, You G, Brown D, Hediger MA.
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The major reabsorptive mechanism for D-glucose in the kidney is known to involve a low affinity high capacity Na+/glucose cotransporter, which is located in the early proximal convoluted tubule segment S1, and which has a Na+ to glucose coupling ratio of 1:1. Here we provide the first molecular evidence for this renal D-glucose reabsorptive mechanism. We report the characterization of a previously cloned human kidney cDNA that codes for a protein with 59% identity to the high affinity Na+/glucose cotransporter (SGLT1). Using expression studies with Xenopus laevis oocytes we demonstrate that this protein (termed SGLT2) mediates saturable Na(+)-dependent and phlorizin-sensitive transport of D-glucose and alpha-methyl-D-glucopyranoside (alpha MeGlc) with Km values of 1.6 mM for alpha MeGlc and approximately 250 to 300 mM for Na+, consistent with low affinity Na+/glucose cotransport. In contrast to SGLT1, SGLT2 does not transport D-galactose. By comparing the initial rate of [14C]-alpha MeGlc uptake with the Na(+)-influx calculated from alpha MeGlc-evoked inward currents, we show that the Na+ to glucose coupling ratio of SGLT2 is 1:1. Using combined in situ hybridization and immunocytochemistry with tubule segment specific marker antibodies, we demonstrate an extremely high level of SGLT2 message in proximal tubule S1 segments. This level of expression was also evident on Northern blots and likely confers the high capacity of this glucose transport system. We conclude that SGLT2 has properties characteristic of the renal low affinity high capacity Na+/glucose cotransporter as previously reported for perfused tubule preparations and brush border membrane vesicles. Knowledge of the structural and functional properties of this major renal Na+/glucose reabsorptive mechanism will advance our understanding of the pathophysiology of renal diseases such as familial renal glycosuria and diabetic renal disorders.
Barfuss,
Differences in active and passive glucose transport along the proximal nephron.
1981, Pubmed
Barfuss,
Differences in active and passive glucose transport along the proximal nephron.
1981,
Pubmed Birnir,
Expression and characterization of the intestinal Na+/glucose cotransporter in COS-7 cells.
1990,
Pubmed
,
Xenbase Bradford,
A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding.
1976,
Pubmed Brown,
Localization of membrane-associated carbonic anhydrase type IV in kidney epithelial cells.
1990,
Pubmed Brownlee,
Advanced glycosylation end products in tissue and the biochemical basis of diabetic complications.
1988,
Pubmed Carney,
Acute effects of streptozotocin diabetes on rat renal function.
1979,
Pubmed Coady,
Sequence homologies among intestinal and renal Na+/glucose cotransporters.
1990,
Pubmed Elsas,
Familial renal glycosuria: a genetic reappraisal of hexose transport by kidney and intestine.
1969,
Pubmed Elsas,
Renal and intestinal hexose transport in familial glucose-galactose malabsorption.
1970,
Pubmed Gluzman,
SV40-transformed simian cells support the replication of early SV40 mutants.
1981,
Pubmed Hannedouche,
Renal hemodynamics and segmental tubular reabsorption in early type 1 diabetes.
1990,
Pubmed Hediger,
Assignment of the human intestinal Na+/glucose cotransporter gene (SGLT1) to the q11.2----qter region of chromosome 22.
1989,
Pubmed Hediger,
Molecular genetics of the human Na+/glucose cotransporter.
1989,
Pubmed
,
Xenbase Hediger,
Expression of size-selected mRNA encoding the intestinal Na/glucose cotransporter in Xenopus laevis oocytes.
1987,
Pubmed
,
Xenbase Hediger,
Expression cloning and cDNA sequencing of the Na+/glucose co-transporter.
,
Pubmed
,
Xenbase Hediger,
Homology of the human intestinal Na+/glucose and Escherichia coli Na+/proline cotransporters.
1989,
Pubmed Ikeda,
Characterization of a Na+/glucose cotransporter cloned from rabbit small intestine.
1989,
Pubmed
,
Xenbase Kanai,
Primary structure and functional characterization of a high-affinity glutamate transporter.
1992,
Pubmed
,
Xenbase Kanai,
Expression of mRNA (D2) encoding a protein involved in amino acid transport in S3 proximal tubule.
1992,
Pubmed
,
Xenbase Kimmich,
Sodium-sugar coupling stoichiometry in chick intestinal cells.
1984,
Pubmed Kumar,
Intracellular sodium in proximal tubules of diabetic rats. Role of glucose.
1988,
Pubmed Loo,
Relaxation kinetics of the Na+/glucose cotransporter.
1993,
Pubmed
,
Xenbase Mager,
Steady states, charge movements, and rates for a cloned GABA transporter expressed in Xenopus oocytes.
1993,
Pubmed
,
Xenbase Morrison,
Sequence comparison of the sodium-D-glucose cotransport systems in rabbit renal and intestinal epithelia.
1991,
Pubmed Pajor,
Molecular evidence for two renal Na+/glucose cotransporters.
1992,
Pubmed
,
Xenbase Parent,
Electrogenic properties of the cloned Na+/glucose cotransporter: I. Voltage-clamp studies.
1992,
Pubmed
,
Xenbase Restrepo,
Kinetic analysis of mechanism of intestinal Na+-dependent sugar transport.
1985,
Pubmed Sabolić,
Localization of ecto-ATPase in rat kidney and isolated renal cortical membrane vesicles.
1992,
Pubmed Schafer,
Transport of metabolic substrates by the proximal nephron.
1985,
Pubmed Thorens,
Differential localization of two glucose transporter isoforms in rat kidney.
1990,
Pubmed Turk,
Glucose/galactose malabsorption caused by a defect in the Na+/glucose cotransporter.
1991,
Pubmed
,
Xenbase Turner,
Sugar uptake into brush border vesicles from normal human kidney.
1977,
Pubmed Turner,
Stoichiometry of cotransport systems.
1985,
Pubmed Turner,
Heterogeneity of sodium-dependent D-glucose transport sites along the proximal tubule: evidence from vesicle studies.
1982,
Pubmed Turner,
Further studies of proximal tubular brush border membrane D-glucose transport heterogeneity.
1982,
Pubmed Turner,
Stoichiometric studies of the renal outer cortical brush border membrane D-glucose transporter.
1982,
Pubmed Wells,
Cloning of a human kidney cDNA with similarity to the sodium-glucose cotransporter.
1992,
Pubmed
,
Xenbase Wells,
Localization of the Na+/glucose cotransporter gene SGLT2 to human chromosome 16 close to the centromere.
1993,
Pubmed