ATP1B2 is the non-catalytic component of the active enzyme, which catalyzes the hydrolysis of ATP coupled with the exchange of Na+ and K+ ions across the plasma membrane. The exact function of the beta-2 subunit is not known. The protein is composed of three subunits: alpha (catalytic), beta and gamma. Recombinant human ATP1B2 protein, fused to His-tag at N-terminus, was expressed in E.coli.