Protein Domain : Epithelial sodium channel, chordates IPR004724

Type	Family
Description	The epithelial Na+ channel (ENaC) proteins consist of sodium channels from animals and has no recognizable homologues in other eukaryotes or bacteria. The vertebrate ENaC proteins from epithelialcells cluster tightly together on the phylogenetic tree: voltage-insensitive ENaC homologues are also found in the brain. Eleven sequenced Caenorhabditis elegans proteins, includingthe degenerins ( ), are distantly related to the vertebrate proteins as well as to each other. At least some of the proteins in this group form part of a mechano-transducing complex for touch sensitivity. Others include the acid-sensing ion channels, ASIC1-3 that are homo- or hetero-oligomeric neuronal H+-gated channels that mediate pain sensation in response to tissue acidosis. Mammalian ENaC is important for the maintenance of Na+ balance and the regulation of blood pressure. Three homologous ENaC subunits, a, b and g, havebeen shown to assemble to form the highly Na+-selective channel.
Short Name	ENaC_chordates