Definition
The epithelial Na+ channel (ENaC) is a member of the ENaC/degenerin family of non-voltage-gated ion channels. This channel is localized in the apical membranes of Na+-absorbing epithelia such as the aldosterone-sensitive distal nephron, respiratory epithelia, and distal colon. ENaC forms a heteromeric channel made of homologous subunits – α, β, and γENaC. The human genes encoding these three subunits are named SCNN1A, SCNN1B, and SCNN1G and are located in chromosome 12 (α) and 16 (β γ), respectively. In humans, but not in mice or rat, a fourth subunit, δENaC, exists. So far, little is known about the physiological role and the functional properties of this additional subunit; δENaC may replace the αENaC subunit to form functional heterotrimers.
Basic Characteristics
Channel Family and Structural Organization
ENaC belongs to the ENaC/degenerin family of ion channels that include in mammals the neuronal acid-sensing ion channels (ASICs) and the bile acid-sensing ion channels...
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References
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Haerteis, S., Kellenberger, S. (2020). Epithelial Na+ Channel. In: Offermanns, S., Rosenthal, W. (eds) Encyclopedia of Molecular Pharmacology. Springer, Cham. https://doi.org/10.1007/978-3-030-21573-6_57-1
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DOI: https://doi.org/10.1007/978-3-030-21573-6_57-1
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