NaV1.6 | sodium voltage-gated channel alpha subunit 8
Alpha subunits consist of four homologous domains (I-IV) with six transmembrane alpha helices (S1–S6) and a pore-forming loop. One a subunit may associate with 1 or 2 b subunits to make up the channel.
NaV1.6: Background Information
The NaV1.6 sodium channel is the most abundantly expressed isoform in the CNS during adulthood and is enriched at the axon initial segment and at the nodes of Ranvier. The channels are highly concentrated in sensory and motor axons in the peripheral nervous system. NaV1.6 facilitates action potential propagation when the membrane potential is depolarized by an influx of Na+ ions. However, NaV1.6 is able to sustain repetitive excitation and firing. The high frequency firing characteristic of NaV1.6 is caused by a persistent and resurgent sodium current. This characteristic is caused by slow activation of the sodium channel following repolarization, which allows a steady-state sodium current after the initial action potential propagation. In macrophages and melanoma cells, isoform 5 may participate in the control of podosome and invadopodia formation. NaV1.6 is TTX-sensitive.
Brain central neurons, dorsal root ganglia, peripheral neurons, glia, Smooth muscle myocytes, corti organ, heart
Action potential initiation, propagation in excitable cells
Cognitive impairment with or without cerebellar ataxia (CIAT), epilepsy (EIEE13)
NEDD4, NEDD4L, β1, β2, β3, β4 subunit, calmodulin, FGF, MAPK14, ankyrin-G
Flecainide, ATX-II, Lidocaine
Patch Clamp: whole cell, room temperature, State- and use-dependence
NaV channel analysis requires GigaOhm seals and a stable and low access resistance
International Union of Pharmacology. XLVII. Nomenclature and Structure-Function Relationships of Voltage-Gated Sodium Channels. Pharmacol Rev 57: 397–409, Catterall, et al. 2005