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. Plays a role in sperm motility.
Subcellular locations: Cell membrane
In mature sperm, located in the principle piece of the sperm flagellum.
Specifically expressed in testis. Found in very low levels in skeletal muscle. Expressed in mature sperm (at protein level).