MaxiK channels are large conductance, voltage and calcium-sensitive potassium channels which are fundamental to the control of smootHuman, Mouseuscle tone and neuronal excitability. MaxiK channels can be formed by 2 subunits: the pore-forming alpha subunit and the product of this gene, the modulatory beta subunit. Intracellular calcium regulates the physical association between the alpha and beta subunits.