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J Membr Biol
2013 Dec 01;24612:915-26. doi: 10.1007/s00232-013-9593-0.
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Relative CO₂/NH₃ permeabilities of human RhAG, RhBG and RhCG.
Geyer RR, Parker MD, Toye AM, Boron WF, Musa-Aziz R.
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Mammalian glycosylated rhesus (Rh) proteins include the erythroid RhAG and the nonerythroid RhBG and RhCG. RhBG and RhCG are expressed in multiple tissues, including hepatocytes and the collecting duct (CD) of the kidney. Here, we expressed human RhAG, RhBG and RhCG in Xenopus oocytes (vs. H2O-injected control oocytes) and used microelectrodes to monitor the maximum transient change in surface pH (DpHS) caused by exposing the same oocyte to 5 % CO₂/33 mM HCO₃⁻ (an increase) or 0.5 mM NH₃/NH₄⁺ (a decrease). Subtracting the respective values for day-matched, H₂O-injected control oocytes yielded channel-specific values (*). (ΔpH*(S))(CO₂) and (-ΔpH*(S))(NH₃) were each significantly >0 for all channels, indicating that RhBG and RhCG--like RhAG--can carry CO₂ and NH₃. We also investigated the role of a conserved aspartate residue, which was reported to inhibit NH₃ transport. However, surface biotinylation experiments indicate the mutants RhBG(D178N) and RhCG(D177N) have at most a very low abundance in the oocyteplasma membrane. We demonstrate for the first time that RhBG and RhCG--like RhAG--have significant CO₂ permeability, and we confirm that RhAG, RhBG and RhCG all have significant NH₃ permeability. However, as evidenced by (ΔpH*(S))(CO₂)/ (-ΔpH*(S))(NH₃) values, we could not distinguish among the CO₂/ NH₃ permeability ratios for RhAG, RhBG and RhCG. Finally, we propose a mechanism whereby RhBG and RhCG contribute to acid secretion in the CD by enhancing the transport of not only NH₃ but also CO₂ across the membranes of CD cells.
Attmane-Elakeb,
Ammonium carriers in medullary thick ascending limb.
2001, Pubmed
Attmane-Elakeb,
Ammonium carriers in medullary thick ascending limb.
2001,
Pubmed Bakouh,
The challenge of understanding ammonium homeostasis and the role of the Rh glycoproteins.
2006,
Pubmed
,
Xenbase Bishop,
Role of the Rhesus glycoprotein, Rh B glycoprotein, in renal ammonia excretion.
2010,
Pubmed Biver,
A role for Rhesus factor Rhcg in renal ammonium excretion and male fertility.
2008,
Pubmed Boron,
Intracellular pH regulation in the renal proximal tubule of the salamander. Basolateral HCO3- transport.
1983,
Pubmed Brion,
Micro-method for the measurement of carbonic anhydrase activity in cellular homogenates.
1988,
Pubmed Brown,
RhCG is the major putative ammonia transporter expressed in the human kidney, and RhBG is not expressed at detectable levels.
2009,
Pubmed Bruce,
The monovalent cation leak in overhydrated stomatocytic red blood cells results from amino acid substitutions in the Rh-associated glycoprotein.
2009,
Pubmed
,
Xenbase Cooper,
Effect of PCMBS on CO2 permeability of Xenopus oocytes expressing aquaporin 1 or its C189S mutant.
1998,
Pubmed
,
Xenbase Eladari,
Expression of RhCG, a new putative NH(3)/NH(4)(+) transporter, along the rat nephron.
2002,
Pubmed Endeward,
RhAG protein of the Rhesus complex is a CO2 channel in the human red cell membrane.
2008,
Pubmed Endeward,
Evidence that aquaporin 1 is a major pathway for CO2 transport across the human erythrocyte membrane.
2006,
Pubmed
,
Xenbase Geyer,
Movement of NH₃ through the human urea transporter B: a new gas channel.
2013,
Pubmed
,
Xenbase Geyer,
Relative CO(2)/NH(3) selectivities of mammalian aquaporins 0-9.
2013,
Pubmed
,
Xenbase Gruswitz,
Function of human Rh based on structure of RhCG at 2.1 A.
2010,
Pubmed Han,
Expression of the ammonia transporter, rh C glycoprotein, in normal and neoplastic human kidney.
2006,
Pubmed Han,
Expression of the ammonia transporter family member, Rh B Glycoprotein, in the human kidney.
2013,
Pubmed Han,
Expression of the gas-transporting proteins, Rh B glycoprotein and Rh C glycoprotein, in the murine lung.
2009,
Pubmed Herrera,
Aquaporin-1 transports NO across cell membranes.
2006,
Pubmed Herrera,
Novel role of AQP-1 in NO-dependent vasorelaxation.
2007,
Pubmed Javelle,
Ammonium sensing in Escherichia coli. Role of the ammonium transporter AmtB and AmtB-GlnK complex formation.
2004,
Pubmed Kaldenhoff,
Aquaporins in plants.
2006,
Pubmed Kaldenhoff,
Mechanisms underlying CO2 diffusion in leaves.
2012,
Pubmed Kim,
Basolateral expression of the ammonia transporter family member Rh C glycoprotein in the mouse kidney.
2009,
Pubmed Lee,
Effect of intercalated cell-specific Rh C glycoprotein deletion on basal and metabolic acidosis-stimulated renal ammonia excretion.
2010,
Pubmed Lee,
Collecting duct-specific Rh C glycoprotein deletion alters basal and acidosis-stimulated renal ammonia excretion.
2009,
Pubmed Lopez,
The ammonium transporter RhBG: requirement of a tyrosine-based signal and ankyrin-G for basolateral targeting and membrane anchorage in polarized kidney epithelial cells.
2005,
Pubmed Ludewig,
Electroneutral ammonium transport by basolateral rhesus B glycoprotein.
2004,
Pubmed
,
Xenbase Mak,
Characterization of ammonia transport by the kidney Rh glycoproteins RhBG and RhCG.
2006,
Pubmed
,
Xenbase Marini,
Structural involvement in substrate recognition of an essential aspartate residue conserved in Mep/Amt and Rh-type ammonium transporters.
2006,
Pubmed Musa-Aziz,
Using fluorometry and ion-sensitive microelectrodes to study the functional expression of heterologously-expressed ion channels and transporters in Xenopus oocytes.
2010,
Pubmed
,
Xenbase Musa-Aziz,
Relative CO2/NH3 selectivities of AQP1, AQP4, AQP5, AmtB, and RhAG.
2009,
Pubmed
,
Xenbase Musa-Aziz,
Concentration-dependent effects on intracellular and surface pH of exposing Xenopus oocytes to solutions containing NH3/NH4(+).
2009,
Pubmed
,
Xenbase Nagami,
Luminal secretion of ammonia in the mouse proximal tubule perfused in vitro.
1988,
Pubmed Nakhoul,
Effect of expressing the water channel aquaporin-1 on the CO2 permeability of Xenopus oocytes.
1998,
Pubmed
,
Xenbase Nakhoul,
Transport of NH(3)/NH in oocytes expressing aquaporin-1.
2001,
Pubmed
,
Xenbase Quentin,
RhBG and RhCG, the putative ammonia transporters, are expressed in the same cells in the distal nephron.
2003,
Pubmed Ripoche,
Role of RhAG and AQP1 in NH3 and CO2 gas transport in red cell ghosts: a stopped-flow analysis.
2006,
Pubmed Ripoche,
Human Rhesus-associated glycoprotein mediates facilitated transport of NH(3) into red blood cells.
2004,
Pubmed Romero,
Expression cloning and characterization of a renal electrogenic Na+/HCO3- cotransporter.
1997,
Pubmed
,
Xenbase Romero,
Molecular pathophysiology of SLC4 bicarbonate transporters.
2005,
Pubmed Seshadri,
Renal expression of the ammonia transporters, Rhbg and Rhcg, in response to chronic metabolic acidosis.
2006,
Pubmed Singh,
An apical permeability barrier to NH3/NH4+ in isolated, perfused colonic crypts.
1995,
Pubmed Somersalo,
A reaction-diffusion model of CO2 influx into an oocyte.
2012,
Pubmed
,
Xenbase Toye,
Band 3 Courcouronnes (Ser667Phe): a trafficking mutant differentially rescued by wild-type band 3 and glycophorin A.
2008,
Pubmed
,
Xenbase Uehlein,
The Arabidopsis aquaporin PIP1;2 rules cellular CO(2) uptake.
2012,
Pubmed Uehlein,
The tobacco aquaporin NtAQP1 is a membrane CO2 pore with physiological functions.
2003,
Pubmed
,
Xenbase Verlander,
Localization of the ammonium transporter proteins RhBG and RhCG in mouse kidney.
2003,
Pubmed Wagner,
The rhesus protein RhCG: a new perspective in ammonium transport and distal urinary acidification.
2011,
Pubmed Wagner,
Regulated acid-base transport in the collecting duct.
2009,
Pubmed Waisbren,
Unusual permeability properties of gastric gland cells.
1994,
Pubmed Weiner,
Role of NH3 and NH4+ transporters in renal acid-base transport.
2011,
Pubmed Weiner,
Molecular physiology of the Rh ammonia transport proteins.
2010,
Pubmed Zidi-Yahiaoui,
Human Rhesus B and Rhesus C glycoproteins: properties of facilitated ammonium transport in recombinant kidney cells.
2005,
Pubmed
