KCa2.3 is a member of the Ca2+-activated K+ channels family with small conductance that includes KCa2.1 (SK1) and KCa2.2 (SK2). The channel is voltage insensitive and is activated by intracellular Ca2+ in the submicromolar range. It has, though, a similar topology to that of voltage-dependent K+ channels (Kv channels), that is six transmembrane domains and intracellular N- and C-termini. The functional channel of all the KCa2 family members is a multimeric protein composed of four pore-forming subunits
