This is the catalytic component of the active enzyme, which catalyzes the hydrolysis of ATP coupled with the exchange of sodium and potassium ions across the plasma membrane. This action creates the electrochemical gradient of sodium and potassium ions, providing the energy for active transport of various nutrients. ATP + H2O + K(+)(out) + Na(+)(in) = ADP + H(+) + K(+)(in) + Na(+)(out) + phosphate The sodium/potassium-transporting ATPase is composed of a catalytic alpha subunit, an auxiliary non-catalytic beta subunit and an additional regulatory subunit. Interacts with regulatory subunit FXYD1 (PubMed:17283221). Interacts with regulatory subunit FXYD3 (PubMed:15743908). Interacts with SIK1 (By similarity). Interacts with SLC35G1 and STIM1 (By similarity). Interacts with CLN3; this interaction regulates the sodium/potassium-transporting ATPase complex localization at the plasma membrane (By similarity). Phosphorylation on Tyr-10 modulates pumping activity. Phosphorylation of Ser-943 by PKA modulates the response of ATP1A1 to PKC. Dephosphorylation by protein phosphatase 2A (PP2A) following increases in intracellular sodium, leading to increase catalytic activity (By similarity). Belongs to the cation transport ATPase (P-type) (TC 3.A.3) family. Type IIC subfamily.