Na+ channel Nav1.9: in search of a gating mechanism.

Voltage-gated Na(+) channels play key roles in generating and propagating action potentials. Their gating is believed to rely exclusively on changes in membrane potential. However, recent data from Blum, Kafitz and Konnerth provide direct evidence that the opening of Na(v)1.9, a member of the voltage-gated Na(+) channel family, is mediated by ligand binding rather than by voltage. This is arguably one of the most influential ideas brought to us in the history of the Na(+) channel field.