Genomes and Genes
Experts and Doctors on symporters in Switzerland
- Bacic D, Capuano P, Baum M, Zhang J, Stange G, Biber J, et al. Activation of dopamine D1-like receptors induces acute internalization of the renal Na+/phosphate cotransporter NaPi-IIa in mouse kidney and OK cells. Am J Physiol Renal Physiol. 2005;288:F740-7 pubmed..In summary, dopamine induces internalization of NaPi-IIa by activation of luminal D(1)-like receptors, an effect that is mediated by PKA. ..
- Lambert G, Traebert M, Biber J, Murer H. Cleavage of disulfide bonds leads to inactivation and degradation of the type IIa, but not type IIb sodium phosphate cotransporter expressed in Xenopus laevis oocytes. J Membr Biol. 2000;176:143-9 pubmed..Sequence comparisons suggest the involvement/presence of different disulfide bonds in type IIa and type IIb Na/P(i)-cotransporters. ..
- Lambert G, Forster I, Biber J, Murer H. Cysteine residues and the structure of the rat renal proximal tubular type II sodium phosphate cotransporter (rat NaPi IIa). J Membr Biol. 2000;176:133-41 pubmed..A revised secondary structure is proposed which includes two partially repeated motifs that are connected by disulfide bridges formed between cysteine pairs C306-C334 and C225-C520. ..
- Frei P, Gao B, Hagenbuch B, Mate A, Biber J, Murer H, et al. Identification and localization of sodium-phosphate cotransporters in hepatocytes and cholangiocytes of rat liver. Am J Physiol Gastrointest Liver Physiol. 2005;288:G771-8 pubmed..We conclude that NaPi-IIb is most probably involved in the reabsorption of P(i) from primary hepatic bile and thus might play an important role in the regulation of biliary P(i) concentration...
- Forster I, Loo D, Eskandari S. Stoichiometry and Na+ binding cooperativity of rat and flounder renal type II Na+-Pi cotransporters. Am J Physiol. 1999;276:F644-9 pubmed..8 (flounder) and 2.5 (rat). Therefore, despite significant differences in the apparent Na+ binding cooperativity, the estimated Na+:Pi stoichiometry was the same for both isoforms. ..
- Hilfiker H, Hattenhauer O, Traebert M, Forster I, Murer H, Biber J. Characterization of a murine type II sodium-phosphate cotransporter expressed in mammalian small intestine. Proc Natl Acad Sci U S A. 1998;95:14564-9 pubmed..Expression of the type IIb protein in the brush borders of enterocytes and transport characteristics suggest that the described type IIb Na/Pi-cotransporter represents a candidate for small intestinal apical Na/Pi-cotransport. ..
- Pfister M, Ruf I, Stange G, Ziegler U, Lederer E, Biber J, et al. Parathyroid hormone leads to the lysosomal degradation of the renal type II Na/Pi cotransporter. Proc Natl Acad Sci U S A. 1998;95:1909-14 pubmed
- Steiling H, Longet K, Moodycliffe A, Mansourian R, Bertschy E, Smola H, et al. Sodium-dependent vitamin C transporter isoforms in skin: Distribution, kinetics, and effect of UVB-induced oxidative stress. Free Radic Biol Med. 2007;43:752-62 pubmed
- Lotscher M, Kaissling B, Biber J, Murer H, Kempson S, Levi M. Regulation of rat renal Na/Pi-cotransporter by parathyroid hormone: immunohistochemistry. Kidney Int. 1996;49:1010-1 pubmed
- Magagnin S, Werner A, Markovich D, Sorribas V, Stange G, Biber J, et al. Expression cloning of human and rat renal cortex Na/Pi cotransport. Proc Natl Acad Sci U S A. 1993;90:5979-83 pubmed..8 kb) was observed only in the lung (human). We conclude that we have structurally identified two closely related proteins most likely involved in human and rat renal brush border Na/Pi cotransport. ..
- Radanovic T, Wagner C, Murer H, Biber J. Regulation of intestinal phosphate transport. I. Segmental expression and adaptation to low-P(i) diet of the type IIb Na(+)-P(i) cotransporter in mouse small intestine. Am J Physiol Gastrointest Liver Physiol. 2005;288:G496-500 pubmed..Furthermore, we conclude that along the entire mouse small intestine, low-phosphate diet affects transcription and/or the stability of NaPi-IIb mRNA. ..
- Geier A, Martin I, Dietrich C, Balasubramaniyan N, Strauch S, Suchy F, et al. Hepatocyte nuclear factor-4alpha is a central transactivator of the mouse Ntcp gene. Am J Physiol Gastrointest Liver Physiol. 2008;295:G226-33 pubmed publisher..Using Hepa 1-6 cells, HNF-4alpha-knockdown resulted in a significant 95% reduction in NTCP mRNA. In conclusion, mouse Ntcp is regulated by HNF-4alpha via a conserved distal cis-element independently of HNF-1alpha. ..
- Ehnes C, Forster I, Bacconi A, Kohler K, Biber J, Murer H. Structure-function relations of the first and fourth extracellular linkers of the type IIa Na+/Pi cotransporter: II. Substrate interaction and voltage dependency of two functionally important sites. J Gen Physiol. 2004;124:489-503 pubmed..The simulations predict that cys substitution at Gly-134 or cys modification of Cys-533 alters the preferred orientation of the empty carrier from an inward to outward-facing conformation for hyperpolarizing voltages. ..
- Wagner C, Devuyst O, Bourgeois S, Mohebbi N. Regulated acid-base transport in the collecting duct. Pflugers Arch. 2009;458:137-56 pubmed publisher..Dysregulation of intercalated cell function or abundance causes various syndromes of distal renal tubular acidosis underlining the importance of these processes for acid-base homeostasis...
- Fiumelli H, Briner A, Puskarjov M, Blaesse P, Belem B, Dayer A, et al. An ion transport-independent role for the cation-chloride cotransporter KCC2 in dendritic spinogenesis in vivo. Cereb Cortex. 2013;23:378-88 pubmed publisher..Collectively, these results demonstrate a role for KCC2 in excitatory synaptogenesis in vivo through a mechanism that is independent of its ion transport function. ..
- Gao B, St Pierre M, Stieger B, Meier P. Differential expression of bile salt and organic anion transporters in developing rat liver. J Hepatol. 2004;41:201-8 pubmed..Here, we investigated the ontogenesis of the polar expression of hepatocellular organic anion and bile salt transport systems in rat liver...
- Jung D, Hagenbuch B, Fried M, Meier P, Kullak Ublick G. Role of liver-enriched transcription factors and nuclear receptors in regulating the human, mouse, and rat NTCP gene. Am J Physiol Gastrointest Liver Physiol. 2004;286:G752-61 pubmed..Bile acids may regulate NTCP/Ntcp indirectly by modulating the capacity of nuclear factors to activate gene expression. ..
- Locher K, Bass R, Rees D. Structural biology. Breaching the barrier. Science. 2003;301:603-4 pubmed
- Hernando N, Forster I, Biber J, Murer H. Molecular characteristics of phosphate transporters and their regulation. Exp Nephrol. 2000;8:366-75 pubmed..The intrinsic electrogenicity of NaPi-IIa, has allowed detailed studies of the transport kinetics of NaPi-IIa and, combined with mutagenesis methods, structure-function information at the protein level is emerging. ..
- Hernando N, Sheikh S, Karim Jimenez Z, Galliker H, Forgo J, Biber J, et al. Asymmetrical targeting of type II Na-P(i) cotransporters in renal and intestinal epithelial cell lines. Am J Physiol Renal Physiol. 2000;278:F361-8 pubmed..Our data indicate that the polarized targeting is dependent on molecular determinants most probably located at the COOH terminus of the cotransporters as well as on the cellular context...
- Lotscher M, Scarpetta Y, Levi M, Halaihel N, Wang H, Zajicek H, et al. Rapid downregulation of rat renal Na/P(i) cotransporter in response to parathyroid hormone involves microtubule rearrangement. J Clin Invest. 1999;104:483-94 pubmed
- Custer M, Spindler B, Verrey F, Murer H, Biber J. Identification of a new gene product (diphor-1) regulated by dietary phosphate. Am J Physiol. 1997;273:F801-6 pubmed..Further characterizations of diphor-1 will show whether diphor-1 is primarily or secondarily involved in the response to dietary Pi. ..
- Hartmann C, Hewson A, Kos C, Hilfiker H, Soumounou Y, Murer H, et al. Structure of murine and human renal type II Na+-phosphate cotransporter genes (Npt2 and NPT2). Proc Natl Acad Sci U S A. 1996;93:7409-14 pubmed
- Norbis F, Perego C, Markovich D, Stange G, Verri T, Murer H. cDNA cloning of a rat small-intestinal Na+/SO4(2-) cotransporter. Pflugers Arch. 1994;428:217-23 pubmed..It differs to the renal NaSi-1 only in the length of the 3' untranslated region, suggesting that the major difference lies in the differential use of polyadenylation signals. ..
- Kohler K, Forster I, Stange G, Biber J, Murer H. Identification of functionally important sites in the first intracellular loop of the NaPi-IIa cotransporter. Am J Physiol Renal Physiol. 2002;282:F687-96 pubmed..We suggest that ICL-1 and ECL-3 sites contribute to the transport pathway and that site N199 is implicated in defining the transport mode. ..
- Stauber A, Radanovic T, Stange G, Murer H, Wagner C, Biber J. Regulation of intestinal phosphate transport. II. Metabolic acidosis stimulates Na(+)-dependent phosphate absorption and expression of the Na(+)-P(i) cotransporter NaPi-IIb in small intestine. Am J Physiol Gastrointest Liver Physiol. 2005;288:G501-6 pubmed
- Bacconi A, Virkki L, Biber J, Murer H, Forster I. Renouncing electroneutrality is not free of charge: switching on electrogenicity in a Na+-coupled phosphate cotransporter. Proc Natl Acad Sci U S A. 2005;102:12606-11 pubmed..Our findings demonstrate that, through a minimal number of side chain substitutions, we can effect a switch from electroneutral to electrogenic cotransporter function, concomitant with the appearance of a cosubstrate interaction site. ..
- Forster I, Hernando N, Biber J, Murer H. The voltage dependence of a cloned mammalian renal type II Na+/Pi cotransporter (NaPi-2). J Gen Physiol. 1998;112:1-18 pubmed..These findings were incorporated into an ordered kinetic model whereby Na+ is the first and last substrate to bind, and the observed voltage dependence arises from the unloaded carrier and first Na+ binding step...
- Verri T, Markovich D, Perego C, Norbis F, Stange G, Sorribas V, et al. Cloning of a rabbit renal Na-Pi cotransporter, which is regulated by dietary phosphate. Am J Physiol. 1995;268:F626-33 pubmed..Thus rabbit proximal tubular BBMs contain two different Na-Pi cotransport systems: NaPi-1 (type I) and NaPi-6 (type II). Only the type II transport system seems to be under regulatory control in response to low-Pi dietary intake...