The bacterial K+ channel structure and its implications for neuronal channels

Voltage-gated K+ (Kv) channels play a central role in generating action pot entials and rhythmic patterns, as well as in dendritic signal processing in neurons. Recently, the first structure of a member of the K+ channel famil y was solved. Although this channel is from bacteria and has a streamlined body plan with no voltage gating, it establishes the architecture of the fu nctional cope of the voltage-gated (K+) channels and their relatives. This architecture explains the crucial features of ion permeation and blockade, and gives some strong hints about gating. The bacterial K+ channel structur e is the central piece in a puzzle; it remains to be seen how it will fit t ogether with other domains of the Kv channels, with auxiliary subunits, and with other signal transduction molecules.