Scn7a
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.
Function
Sodium leak channel functioning as an osmosensor regulating sodium ion levels in various tissues and organs. While most sodium channels are voltage-gated, SCN7A is not and lets sodium flow through membrane along its concentration gradient (PubMed:11027237, PubMed:11992118, PubMed:17408578, PubMed:27252474). In glial cells of the central nervous system, senses body-fluid sodium levels and controls salt intake behavior as well as voluntary water intake through activation of nearby neurons to maintain appropriate sodium levels in the body (PubMed:11027237, PubMed:17408578, PubMed:27252474). By mediating sodium influx into keratinocytes, also plays a role in skin barrier homeostasis (By similarity).
Sequence Similarities
Belongs to the sodium channel (TC 1.A.1.10) family. SCN7A subfamily.
Tissue Specificity
Not tissue specific but widely expressed (PubMed:11027237, PubMed:7982916). Expressed in regions of the central nervous system that control body fluid ionic balance (PubMed:11027237).
Cellular localization
- Cell membrane
- Multi-pass membrane protein
Alternative names
Nag, Nav2, scl11, Sodium channel protein type 7 subunit alpha, Nax channel, Sodium channel Nav2.3