The BK channel (calcium-activated potassium channel subunit alpha-1 or KCNMA1) is a potassium channel activated by both membrane depolarization or increase in cytosolic Ca(2+) that mediates e, Xenopus/Amphibian,port of K(+). BK channel is also activated by the concentration of cytosolic Mg(2+). BK channel has a key role in controlling e, Xenopus/Amphibian,citability in a numerous systems, such as smooth muscle contraction, tuning of hair cells in the cochlea, regulation of transmitter release, and innate immunity. Defects in KCNMA1 are the cause of generalized epilepsy and paro, Xenopus/Amphibian,ysmal dyskinesia (GEPD).