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Electroneutral ammonium transport by basolateral rhesus B glycoprotein.
Ludewig U
.
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The liver and kidney are important tissues for ammonium (NH4+/NH3) metabolism and excretion. The rhesus B glycoprotein (RhBG) is a membrane protein expressed in liver and kidney with similarity to NH4+ transporters found in microorganisms, plants and animals. In the kidney, RhBG is predominantly localized to basolateral membranes of distal tubule epithelia, including connecting tubules and collecting ducts. These epithelia display mainly electroneutral ammonium transport, in contrast to other tubular sites, where net NH4+ transport occurs. In accordance with its localization, human RhBG mediates saturable, electroneutral transport of the ammonium analogue methylammonium when heterologously expressed in Xenopus oocytes. Uptake of methylammonium saturates with a Km = 2.6 mm. Methylammonium uptake is inhibited by ammonium and this inhibition saturates with a Ki approximately 3 mm. Electric current measurements and intracellular pHi determinations suggest that RhBG acts as an electroneutral NH4+ -H+ exchanger.
Bakouh,
NH3 is involved in the NH4+ transport induced by the functional expression of the human Rh C glycoprotein.
2004, Pubmed,
Xenbase
Bakouh,
NH3 is involved in the NH4+ transport induced by the functional expression of the human Rh C glycoprotein.
2004,
Pubmed
,
Xenbase
Boldt,
NH(4)(+) conductance in Xenopus laevis oocytes. III. Effect of NH(3).
2003,
Pubmed
,
Xenbase
Burckhardt,
NH4+ conductance in Xenopus laevis oocytes. I. Basic observations.
1997,
Pubmed
,
Xenbase
Burckhardt,
Pathways of NH3/NH4+ permeation across Xenopus laevis oocyte cell membrane.
1992,
Pubmed
,
Xenbase
Cougnon,
Further investigation of ionic diffusive properties and of NH4+ pathways in Xenopus laevis oocyte cell membrane.
1996,
Pubmed
,
Xenbase
Eladari,
Expression of RhCG, a new putative NH(3)/NH(4)(+) transporter, along the rat nephron.
2002,
Pubmed
Flessner,
Permeabilities of rat collecting duct segments to NH3 and NH4+.
1991,
Pubmed
Häussinger,
Hepatocyte heterogeneity in the metabolism of amino acids and ammonia.
1992,
Pubmed
Kikeri,
Cell membranes impermeable to NH3.
1989,
Pubmed
Knepper,
Ammonium transport in the kidney.
1989,
Pubmed
Lande,
The relationship between membrane fluidity and permeabilities to water, solutes, ammonia, and protons.
1995,
Pubmed
Liu,
Characterization of human RhCG and mouse Rhcg as novel nonerythroid Rh glycoprotein homologues predominantly expressed in kidney and testis.
2000,
Pubmed
Liu,
Rh type B glycoprotein is a new member of the Rh superfamily and a putative ammonia transporter in mammals.
2001,
Pubmed
Ludewig,
Rhesus factors and ammonium: a function in efflux?
2001,
Pubmed
Ludewig,
Uniport of NH4+ by the root hair plasma membrane ammonium transporter LeAMT1;1.
2002,
Pubmed
,
Xenbase
Ludewig,
Homo- and hetero-oligomerization of ammonium transporter-1 NH4 uniporters.
2003,
Pubmed
,
Xenbase
Marini,
The Rh (rhesus) blood group polypeptides are related to NH4+ transporters.
1997,
Pubmed
Marini,
The human Rhesus-associated RhAG protein and a kidney homologue promote ammonium transport in yeast.
2000,
Pubmed
Marini,
Cloning and expression of the MEP1 gene encoding an ammonium transporter in Saccharomyces cerevisiae.
1994,
Pubmed
Meier-Wagner,
Multiplicity of ammonium uptake systems in Corynebacterium glutamicum: role of Amt and AmtB.
2001,
Pubmed
Nakhoul,
Non-erythroid Rh glycoproteins: a putative new family of mammalian ammonium transporters.
2004,
Pubmed
Ninnemann,
Identification of a high affinity NH4+ transporter from plants.
1994,
Pubmed
Priver,
Apical membrane of the gastric parietal cell: water, proton, and nonelectrolyte permeabilities.
1993,
Pubmed
Quentin,
RhBG and RhCG, the putative ammonia transporters, are expressed in the same cells in the distal nephron.
2003,
Pubmed
Sasaki,
Regulation mechanisms of intracellular pH of Xenopus laevis oocyte.
1992,
Pubmed
,
Xenbase
Siewe,
Functional and genetic characterization of the (methyl)ammonium uptake carrier of Corynebacterium glutamicum.
1996,
Pubmed
Sohlenkamp,
Characterization of Arabidopsis AtAMT2, a high-affinity ammonium transporter of the plasma membrane.
2002,
Pubmed
Soupene,
Ammonium/methylammonium transport (Amt) proteins facilitate diffusion of NH3 bidirectionally.
2002,
Pubmed
Star,
Disequilibrium pH and ammonia transport in isolated perfused cortical collecting ducts.
1987,
Pubmed
Verlander,
Localization of the ammonium transporter proteins RhBG and RhCG in mouse kidney.
2003,
Pubmed
Wall,
Distribution of luminal carbonic anhydrase activity along rat inner medullary collecting duct.
1991,
Pubmed
Weiner,
Renal and hepatic expression of the ammonium transporter proteins, Rh B Glycoprotein and Rh C Glycoprotein.
2003,
Pubmed
Weiner,
Localization of the ammonium transporters, Rh B glycoprotein and Rh C glycoprotein, in the mouse liver.
2003,
Pubmed
Westhoff,
Identification of the erythrocyte Rh blood group glycoprotein as a mammalian ammonium transporter.
2002,
Pubmed
,
Xenbase
