TCDB is operated by the Saier Lab Bioinformatics Group
Transporter Information:
Name: solute carrier family 9 (sodium/hydrogen exchanger), isoform 5
Symbol: SLC9A5
TC: 2.A.36.1.2
Locations: 16q22.1
Aliases: NHE5
Swiss-Prot: Q14940
Accession Number: NM_004594
PubMed (7759094): Klanke CA, Su YR, Callen DF, Wang Z, Meneton P, Baird N, Kandasamy RA,Orlowski J, Otterud BE, Leppert M, et al. Molecular cloning and physical and genetic mapping of a novel human Na+/H+exchanger (NHE5/SLC9A5) to chromosome 16q22.1.Genomics. 1995 Feb 10;25(3):615-22. PMID: 7759094 [PubMed - indexed for MEDLINE]

A human genomic clone for a novel fifth member of the Na+/H+ exchanger (NHE) family, NHE5 (gene symbol SLC9A5), has been isolated and partially sequenced. The deduced amino acid sequence of two exons, containing 154 codons, exhibits 59-73% identity to the other members of the NHE family, with closest similarity to NHE3. Northern blot analysis demonstrated that the NHE5 gene is expressed in brain, testis, spleen, and skeletal muscle. Fluorescence in situ hybridization analysis of a cosmid containing NHE5 to human metaphase chromosomes localized the NHE5 gene to the cytogenetic interval 16q21-q22. A panel of somatic cell hybrids containing various portions of chromosome 16 was used to refine further the placement of NHE5 within band 16q22.1. A polymorphic dinucleotide (GT/CA)n repeat contained in the NHE5 cosmid was identified and developed into a microsatellite PCR marker. This was typed in a subset of the CEPH (Centre d'Etude du Polymorphisme Humain) families to place it on a genetic map of the human genome. Pairwise linkage analysis of this marker showed that it was linked to marker D16S421 with a maximal lod score of 35.21 at a recombination fraction (theta) of 0.000, in complete concordance with its chromosomal localization by physical mapping. Multipoint linkage analysis placed NHE5 between the flanking markers D16S421 and D16S512. The cloning of this new member of the sodium hydrogen exchanger family, its chromosomal localization, and the discovery of a polymorphic marker for it now make it feasible to study the possible involvement of this gene in disorders of Na+/H+ transport.

PubMed (9933642): Attaphitaya S, Park K, Melvin JE. Molecular cloning and functional expression of a rat Na+/H+ exchanger (NHE5)highly expressed in brain.J Biol Chem. 1999 Feb 12;274(7):4383-8. PMID: 9933642 [PubMed - indexed for MEDLINE]

We report here the cloning, primary structure, heterologous expression, tissue distribution, and localization of a cDNA encoding rat NHE5, a fifth member of the mammalian plasma membrane Na+/H+ exchanger (NHE) gene family. The full-length open reading frame as well as 34 nucleotides of 5'-untranslated and 1443 nucleotides of 3'-untranslated sequences were obtained using a polymerase chain reaction strategy involving reverse transcription-polymerase chain reaction and 5'/3'-rapid amplification of cDNA ends. The NHE5 cDNA encodes a protein of 898 amino acids with a calculated Mr of 99,044 and is predicted to contain 11-13 transmembrane domains. An amino acid comparison of the coding region of rat NHE5 reveals 95% identity with human NHE5. Northern hybridization analysis showed that high level expression of NHE5 mRNA is restricted to brain. Transfection of the coding region of rat NHE5 into NHE-deficient PS120 cells resulted in Na+/H+ exchange activity that was relatively insensitive to the amiloride analogue, 5-(N-ethyl-N-isopropyl) amiloride, with a half-maximal inhibitory concentration (IC50) of 1. 53 +/- 0.25 microM. In situ hybridization of rat brain sections revealed significant NHE5 mRNA levels in the dentate gyrus with lower levels observed in the hippocampus and cerebral cortex. These results suggest a specialized role for this fifth NHE isoform in neuronal tissues.

>sp|Q14940|SL9A5_HUMAN Sodium/hydrogen exchanger 5 OS=Homo sapiens GN=SLC9A5 PE=1 SV=2