FXYD2

FXYD domain containing ion transport regulator 2
NMR structure of the NA,K-ATPASE regulatory protein FXYD2b in micelles. PDB entry 2mkv​
Available structures PDB Ortholog search: PDBe, RCSB List of PDB id codes 2MKV​
Identifiers
Symbols	FXYD2 ; ATP1G1; HOMG2
External IDs	OMIM: 601814 HomoloGene: 86992 IUPHAR: 2610 ChEMBL: 4639 GeneCards: FXYD2 Gene
Gene ontology Molecular function • transporter activity • ion channel activity • sodium:potassium-exchanging ATPase activity • sodium channel regulator activity Cellular component • plasma membrane • integral component of plasma membrane • sodium:potassium-exchanging ATPase complex • basolateral plasma membrane • intracellular membrane-bounded organelle • extracellular exosome Biological process • regulation of cell growth • transport • ion transmembrane transport • sodium ion export from cell • regulation of cell proliferation • transmembrane transport • potassium ion import across plasma membrane • regulation of sodium ion transmembrane transporter activity Sources: Amigo / QuickGO
RNA expression pattern
More reference expression data
Orthologs
Species	Human	Mouse
Entrez	486	11936
Ensembl	ENSG00000137731	ENSMUSG00000059412
UniProt	P54710	Q04646
RefSeq (mRNA)	NM_001127489	NM_007503
RefSeq (protein)	NP_001671	NP_031529
Location (UCSC)	Chr 11: 117.8 – 117.83 Mb	Chr 9: 45.4 – 45.41 Mb
PubMed search

Sodium/potassium-transporting ATPase gamma chain is a protein that in humans is encoded by the FXYD2 gene.^[1][2][3]

This gene encodes a member of a family of small membrane proteins that share a 35-amino acid signature sequence domain, beginning with the sequence PFXYD and containing 7 invariant and 6 highly conserved amino acids. The approved human gene nomenclature for the family is FXYD-domain containing ion transport regulator. Mouse FXYD5 has been termed RIC (Related to Ion Channel). FXYD2, also known as the gamma subunit of the Na,K-ATPase, regulates the properties of that enzyme. FXYD1 (phospholemman), FXYD2 (gamma), FXYD3 (MAT-8), FXYD4 (CHIF), and FXYD5 (RIC) have been shown to induce channel activity in experimental expression systems. Transmembrane topology has been established for two family members (FXYD1 and FXYD2), with the N-terminus extracellular and the C-terminus on the cytoplasmic side of the membrane. The Type III integral membrane protein encoded by this gene is the gamma subunit of the Na,K-ATPase present on the plasma membrane. Although the Na,K-ATPase does not depend on the gamma subunit to be functional, it is thought that the gamma subunit modulates the enzyme's activity by inducing ion channel activity. Mutations in this gene have been associated with renal hypomagnesaemia.^[3]

References

1. Kim JW, Lee Y, Lee IA, Kang HB, Choe YK, Choe IS (Apr 1997). "Cloning and expression of human cDNA encoding Na+, K(+)-ATPase gamma-subunit". Biochim Biophys Acta 1350 (2): 133–5. doi:10.1016/S0167-4781(96)00219-9. PMID 9048881.
2. Meij IC, Saar K, van den Heuvel LP, Nuernberg G, Vollmer M, Hildebrandt F, Reis A, Monnens LA, Knoers NV (Mar 1999). "Hereditary isolated renal magnesium loss maps to chromosome 11q23". Am J Hum Genet 64 (1): 180–8. doi:10.1086/302199. PMC 1377716. PMID 9915957.
3. "Entrez Gene: FXYD2 FXYD domain containing ion transport regulator 2".

Further reading

• Adams MD, Kerlavage AR, Fleischmann RD, et al. (1995). "Initial assessment of human gene diversity and expression patterns based upon 83 million nucleotides of cDNA sequence" (PDF). Nature 377 (6547 Suppl): 3–174. PMID 7566098.
• Austruy E, Cohen-Salmon M, Antignac C, et al. (1993). "Isolation of kidney complementary DNAs down-expressed in Wilms' tumor by a subtractive hybridization approach". Cancer Res. 53 (12): 2888–94. PMID 7916648.
• Therien AG, Goldshleger R, Karlish SJ, Blostein R (1998). "Tissue-specific distribution and modulatory role of the gamma subunit of the Na,K-ATPase". J. Biol. Chem. 272 (51): 32628–34. doi:10.1074/jbc.272.51.32628. PMID 9405479.
• Annabi B, Hiraiwa H, Mansfield BC, et al. (1998). "The gene for glycogen-storage disease type 1b maps to chromosome 11q23". Am. J. Hum. Genet. 62 (2): 400–5. doi:10.1086/301727. PMC 1376902. PMID 9463334.
• Minor NT, Sha Q, Nichols CG, Mercer RW (1998). "The gamma subunit of the Na,K-ATPase induces cation channel activity". Proc. Natl. Acad. Sci. U.S.A. 95 (11): 6521–5. doi:10.1073/pnas.95.11.6521. PMC 27846. PMID 9600999.
• Arystarkhova E, Wetzel RK, Asinovski NK, Sweadner KJ (1999). "The gamma subunit modulates Na(+) and K(+) affinity of the renal Na,K-ATPase". J. Biol. Chem. 274 (47): 33183–5. doi:10.1074/jbc.274.47.33183. PMID 10559186.
• Sweadner KJ, Rael E (2001). "The FXYD gene family of small ion transport regulators or channels: cDNA sequence, protein signature sequence, and expression". Genomics 68 (1): 41–56. doi:10.1006/geno.2000.6274. PMID 10950925.
• Meij IC, Koenderink JB, van Bokhoven H, et al. (2000). "Dominant isolated renal magnesium loss is caused by misrouting of the Na(+),K(+)-ATPase gamma-subunit". Nat. Genet. 26 (3): 265–6. doi:10.1038/81543. PMID 11062458.
• Sweadner KJ, Wetzel RK, Arystarkhova E (2001). "Genomic organization of the human FXYD2 gene encoding the gamma subunit of the Na,K-ATPase". Biochem. Biophys. Res. Commun. 279 (1): 196–201. doi:10.1006/bbrc.2000.3907. PMID 11112438.
• Arystarkhova E, Wetzel RK, Sweadner KJ (2002). "Distribution and oligomeric association of splice forms of Na(+)-K(+)-ATPase regulatory gamma-subunit in rat kidney". Am. J. Physiol. Renal Physiol. 282 (3): F393–407. doi:10.1152/ajprenal.00146.2001. PMID 11832419.
• Strausberg RL, Feingold EA, Grouse LH, et al. (2003). "Generation and initial analysis of more than 15,000 full-length human and mouse cDNA sequences". Proc. Natl. Acad. Sci. U.S.A. 99 (26): 16899–903. doi:10.1073/pnas.242603899. PMC 139241. PMID 12477932.
• Zouzoulas A, Therien AG, Scanzano R, et al. (2003). "Modulation of Na,K-ATPase by the gamma subunit: studies with transfected cells and transmembrane mimetic peptides". J. Biol. Chem. 278 (42): 40437–41. doi:10.1074/jbc.M308610200. PMID 12907667.
• Ota T, Suzuki Y, Nishikawa T, et al. (2004). "Complete sequencing and characterization of 21,243 full-length human cDNAs". Nat. Genet. 36 (1): 40–5. doi:10.1038/ng1285. PMID 14702039.
• Gerhard DS, Wagner L, Feingold EA, et al. (2004). "The Status, Quality, and Expansion of the NIH Full-Length cDNA Project: The Mammalian Gene Collection (MGC)". Genome Res. 14 (10B): 2121–7. doi:10.1101/gr.2596504. PMC 528928. PMID 15489334.
• Gegelashvili M, Rodriguez-Kern A, Sung L, et al. (2007). "Glutamate transporter GLAST/EAAT1 directs cell surface expression of FXYD2/gamma subunit of Na, K-ATPase in human fetal astrocytes". Neurochem. Int. 50 (7–8): 916–20. doi:10.1016/j.neuint.2006.12.015. PMID 17316900.