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Physiological and molecular mechanisms of inorganic phosphate handling in the toad Bufo bufo.
Møbjerg N
,
Werner A
,
Hansen SM
,
Novak I
.
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The aim of this study was to elucidate mechanisms of P(i) handling in toads (Bufo bufo). We introduced toads to experimental solutions of various [P(i)] and high P(i) diets and measured urine and lymph [P(i)]. Both lymph and urine [P(i)] increased with increasing P(i) loads, indicating P(i) absorption across skin and intestine. An initial fragment of a NaPi-II type transporter was amplified from kidney, and the full-length sequence was obtained. The protein showed the molecular hallmarks of NaPi-IIb transporters. When expressed in Xenopus oocytes the clone showed unusual pH dependence, but apparent affinity constants for P(i) and Na(+) were in the range of other NaPi-II transporters. Expression profiling showed that the transporter was present in skin, intestine and kidney. Reverse transcription-polymerase chain reaction assays on dissected renal tubules indicated expression in the collecting duct system. Collecting tubules and ducts were isolated, perfused and microelectrode recordings showed electrogenic P(i) transport in apical and basolateral membranes. Taken together, our results show that P(i) is handled by intestine, kidney and skin. The presently cloned NaPi-IIb is a likely candidate involved in P(i) absorption across these epithelia. In addition, electrophysiological experiments suggest that the collecting duct system plays an important role in P(i) homeostasis.
Bacconi,
Renouncing electroneutrality is not free of charge: switching on electrogenicity in a Na+-coupled phosphate cotransporter.
2005, Pubmed,
Xenbase
Bacconi,
Renouncing electroneutrality is not free of charge: switching on electrogenicity in a Na+-coupled phosphate cotransporter.
2005,
Pubmed
,
Xenbase
Baginski,
Microdetermination of inorganic phosphate, phospholipids, and total phosphate in biologic materials.
1967,
Pubmed
Beyenbach,
Kidneys sans glomeruli.
2004,
Pubmed
Biber,
PDZ interactions and proximal tubular phosphate reabsorption.
2004,
Pubmed
Collins,
The SLC20 family of proteins: dual functions as sodium-phosphate cotransporters and viral receptors.
2004,
Pubmed
Custer,
Localization of NaPi-1, a Na-Pi cotransporter, in rabbit kidney proximal tubules. I. mRNA localization by reverse transcription/polymerase chain reaction.
1993,
Pubmed
,
Xenbase
Elger,
Na-P(i) cotransport sites in proximal tubule and collecting tubule of winter flounder (Pleuronectes americanus).
1998,
Pubmed
Forster,
Forging the link between structure and function of electrogenic cotransporters: the renal type IIa Na+/Pi cotransporter as a case study.
2002,
Pubmed
Graham,
Characterization of a type IIb sodium-phosphate cotransporter from zebrafish (Danio rerio) kidney.
2003,
Pubmed
,
Xenbase
HOGBEN,
Excretion of phosphate by isolated frog kidney; an 'adsorption semipermeability' model for maximal tubular transport.
1951,
Pubmed
Hilfiker,
Characterization of a murine type II sodium-phosphate cotransporter expressed in mammalian small intestine.
1998,
Pubmed
,
Xenbase
Ishizuya-Oka,
Temporal and spatial expression of an intestinal Na+/PO4 3- cotransporter correlates with epithelial transformation during thyroid hormone-dependent frog metamorphosis.
1997,
Pubmed
,
Xenbase
Jensen,
Proton pump-driven cutaneous chloride uptake in anuran amphibia.
2003,
Pubmed
Jørgensen,
200 years of amphibian water economy: from Robert Townson to the present.
1997,
Pubmed
Kennedy,
Optimal absorptive transport of the dipeptide glycylsarcosine is dependent on functional Na+/H+ exchange activity.
2002,
Pubmed
,
Xenbase
Kohl,
Na-Pi cotransport in flounder: same transport system in kidney and intestine.
1996,
Pubmed
,
Xenbase
Murer,
The sodium phosphate cotransporter family SLC34.
2004,
Pubmed
Murer,
Proximal tubular phosphate reabsorption: molecular mechanisms.
2000,
Pubmed
Møbjerg,
K(+) transport in the mesonephric collecting duct system of the toad Bufo bufo: microelectrode recordings from isolated and perfused tubules.
2002,
Pubmed
Møbjerg,
Ion transport mechanisms in the mesonephric collecting duct system of the toad Bufo bufo: microelectrode recordings from isolated and perfused tubules.
2004,
Pubmed
Møbjerg,
Morphology of the kidney in the West African caecilian, Geotrypetes seraphini (Amphibia, Gymnophiona, Caeciliidae).
2004,
Pubmed
Nalbant,
Functional characterization of a Na+-phosphate cotransporter (NaPi-II) from zebrafish and identification of related transcripts.
1999,
Pubmed
,
Xenbase
Reimer,
Organic anion transport is the primary function of the SLC17/type I phosphate transporter family.
2004,
Pubmed
Uchiyama,
Hormonal regulation of ion and water transport in anuran amphibians.
2006,
Pubmed
Werner,
Cloning and expression of cDNA for a Na/Pi cotransport system of kidney cortex.
1991,
Pubmed
,
Xenbase
Werner,
Evolution of the Na-P(i) cotransport systems.
2001,
Pubmed
,
Xenbase
Werner,
Cloning and expression of a renal Na-Pi cotransport system from flounder.
1994,
Pubmed
,
Xenbase