Enables P-type sodium:potassium-exchanging transporter activity. Involved in flagellated sperm motility; regulation of cellular pH; and spermatogenesis. Predicted to be located in rod photoreceptor outer segment and sperm midpiece. Predicted to be part of sodium:potassium-exchanging ATPase complex. Orthologous to human ATP1A4 (ATPase Na+/K+ transporting subunit alpha 4). [provided by Alliance of Genome Resources, Apr 2022]