 In this inactivated conformation, the channel cannot open, even if the transmembrane voltage is favorable.The amino terminal domain of the K+ channel or an auxiliary protein can mediate "N-type" inactivation.The mechanism of this type of inactivation has been described as a "ball and chain" model, where the N-terminus of the protein forms a ball that is tethered to the rest of the protein through a loop (the chain).