ArticleThe Journal of membrane biology2005
Functionally important residues in the predicted 3(rd) transmembrane domain of the type IIa sodium-phosphate co-transporter (NaPi-IIa).
Article in The Journal of membrane biology, 2005. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 12 papers.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
12 citing papers in PubMed, 23 citations in OpenAlex.
- Functional role of a structural water in the elevator domain of dicarboxylate transporter VcINDY.PNAS nexus · 2026Article
- The molecular mechanism of SLC34 proteins: insights from two decades of transport assays and structure-function studies.Pflugers Archiv : European journal of physiology · 2019Review
- Structural models of the NaPi-II sodium-phosphate cotransporters.Pflugers Archiv : European journal of physiology · 2019Review
- Autosomal-Recessive Mutations in SLC34A1 Encoding Sodium-Phosphate Cotransporter 2A Cause Idiopathic Infantile Hypercalcemia.Journal of the American Society of Nephrology : JASN · 2016Article
- Identification of the first sodium binding site of the phosphate cotransporter NaPi-IIa (SLC34A1).Biophysical journal · 2015Article
- Structural fold and binding sites of the human Na⁺-phosphate cotransporter NaPi-II.Biophysical journal · 2014Article
- Conferring electrogenicity to the electroneutral phosphate cotransporter NaPi-IIc (SLC34A3) reveals an internal cation release step.Pflugers Archiv : European journal of physiology · 2013Article
- Voltage- and substrate-dependent interactions between sites in putative re-entrant domains of a Na(+)-coupled phosphate cotransporter.Pflugers Archiv : European journal of physiology · 2011Article
- Substrate interactions of the electroneutral Na+-coupled inorganic phosphate cotransporter (NaPi-IIc).The Journal of physiology · 2009Article
- Temperature dependence of steady-state and presteady-state kinetics of a type IIb Na+/P i cotransporter.The Journal of membrane biology · 2007Article
- Topology of the type IIa Na+/P(i) cotransporter.The Journal of membrane biology · 2006Article
- Electrogenic kinetics of a mammalian intestinal type IIb Na(+)/P(i) cotransporter.The Journal of membrane biology · 2006Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
5 authors at 2 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
The type IIa Na(+)/P(i), cotransporter (NaPi-IIa) mediates electrogenic transport of three Na(+) and one divalent P(i) ion (and one net positive charge) across the cell membrane. Sequence comparison of electrogenic NaPi-IIa and IIb isoforms with the electroneutral NaPi-IIc isoform pointed to the third transmembrane domain (TMD-3) as a possibly significant determinant of substrate binding. To elucidate the role of TMD-3 in the topology and mechanism underlying NaPi-IIa function we subjected it to cysteine scanning mutagenesis. The constructs were expressed in Xenopus oocytes and P(i) transport kinetics were assayed by electrophysiology and radiotracer uptake. Cys substitution resulted in only marginally altered kinetics of P(i) transport in those mutants providing sufficient current for analysis. Only one site, at the extracellular end of TMD-3, appeared to be accessible to methanethiosulfonate reagents. However, additional mutations carried out at D224 (replaced by E, G or N) and N227 (replaced by D or Q) resulted in markedly altered voltage and substrate dependencies of the P(i)-dependent currents. Replacing Asp-224 (highly conserved in electrogenic a and b isoforms) with Gly (the residue found in the electroneutral c isoform) resulted in a mutant that mediated electroneutral Na(+)-dependent P(i) transport. Since electrogenic NaPi-II transports 3 Na(+)/transport cycle, whereas electroneutral NaPi-IIc only transports 2, we speculate that this loss of electrogenicity might result from the loss of one of the three Na(+) binding sites in NaPi-IIa.
Indexed as
Identifiers
What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.