Using mutagenesis to study potassium channel mechanisms.

The voltage-activated K+ channels are members of an ion channel family that includes the voltage-activated Na+ and Ca2+ channels. These ion channels mediate the transmembrane ionic currents that are responsible for the electrical signals produced by cells. The recent cloning of numerous voltage-activated K+ channels has made it possible to combine molecular-genetic and biophysical methods to study K+ channel mechanisms. These mutagenesis-function studies are beginning to provide new information about the architecture of K+ channel proteins and how they form a voltage-gated, K(+)-selective pore.