Mediates the voltage-dependent sodium ion permeability of excitable membranes. Assuming opened or closed conformations in response to the voltage difference across the membrane, the protein forms a sodium-selective channel through which Na(+) ions may pass in accordance with their electrochemical gradient. In macrophages and melanoma cells, isoform 5 may participate in the control of podosome and invadopodia formation.
Isoform 5 is expressed in non-neuronal tissues, such as monocytes/macrophages.
Belongs to the sodium channel (TC 1.A.1.10) family. Nav1.6/SCN8A subfamily. Contains 1 IQ domain.
The sequence contains 4 internal repeats, each with 5 hydrophobic segments (S1,S2,S3,S5,S6) and one positively charged segment (S4). Segments S4 are probably the voltage-sensors and are characterized by a series of positively charged amino acids at every third position.
May be ubiquitinated by NEDD4L; which would promote its endocytosis.
Membrane and Cytoplasmic vesicle. Some vesicles are localized adjacent to melanoma invadopodia and macrophage podosomes. Does not localize to the plasma membrane.