IDENTIFICATION OF PN1, A PREDOMINANT VOLTAGE-DEPENDENT SODIUM-CHANNELEXPRESSED PRINCIPALLY IN PERIPHERAL NEURONS

Membrane excitability in different tissues is due, in Large part, to t he selective expression of distinct genes encoding the voltage-depende nt sodium channel, Although the predominant sodium channels in brain, skeletal muscle, and cardiac muscle have been identified, the major so dium channel types responsible for excitability within the peripheral nervous system have remained elusive, We now describe the deduced prim ary structure of a sodium channel, peripheral nerve type 1 (PN1), whic h is expressed at high levels throughout the peripheral nervous system and is targeted to nerve terminals of cultured dorsal root ganglion n eurons, Studies using cultured PC12 cells indicate that both expressio n and targeting of PN1 is induced by treatment of the cells with nerve growth factor, The preferential Localization suggests that the PN1 so dium channel plays a specific role in nerve excitability.