Sodium/potassium-transporting ATPase subunit alpha-4 is an enzyme that in humans is encoded by the ATP1A4gene.
The protein encoded by this gene belongs to the family of P-type cation transport ATPases, and to the subfamily of Na+/K+ -ATPases. Na+/K+ -ATPase is an integral membrane protein responsible for establishing and maintaining the electrochemical gradients of Na and K ions across the plasma membrane. These gradients are essential for osmoregulation, for sodium-coupled transport of a variety of organic and inorganic molecules, and for electrical excitability of nerve and muscle. This enzyme is composed of two subunits, a large catalytic subunit (alpha) and a smaller glycoprotein subunit (beta). The catalytic subunit of Na+/K+ -ATPase is encoded by multiple genes. This gene encodes an alpha 4 subunit. Alternatively spliced transcript variants encoding different isoforms have been identified.
Sverdlov ED, Broude NE, Sverdlov VE et al. (1987). "Family of Na+,K+-ATPase genes. Intra-individual tissue-specific restriction fragment length polymorphism". FEBS Lett.221 (1): 129–33. doi:10.1016/0014-5793(87)80366-6. PMID2887455.
Sverdlov ED, Monastyrskaya GS, Broude NE et al. (1987). "The family of human Na+,K+-ATPase genes. No less than five genes and/or pseudogenes related to the alpha-subunit". FEBS Lett.217 (2): 275–8. doi:10.1016/0014-5793(87)80677-4. PMID3036582.
Hlivko JT, Chakraborty S, Hlivko TJ et al. (2006). "The human Na, K-ATPase alpha 4 isoform is an ouabain-sensitive alpha isoform that is expressed in sperm". Mol. Reprod. Dev.73 (1): 101–15. doi:10.1002/mrd.20383. PMID16175638.
Gregory SG, Barlow KF, McLay KE et al. (2006). "The DNA sequence and biological annotation of human chromosome 1". Nature441 (7091): 315–21. doi:10.1038/nature04727. PMID16710414.
Rodova M, Nguyen AN, Blanco G (2006). "The transcription factor CREMtau and cAMP regulate promoter activity of the Na, K-ATPase alpha4 isoform". Mol. Reprod. Dev.73 (11): 1435–47. doi:10.1002/mrd.20518. PMID16894555.