ENaC | Epithelial Sodium Channel | Amiloride-sensitive Sodium Channel

Family:
Epithelial sodium channels, member of the ENaC/Degenerin superfamily

Topology:
ENaC is assembled as a heterotrimer composed of three homologous subunits α or δ, β, and γ. These subunits are encoded by four genes: SCNN1A, SCNN1B, SCNN1G, and SCNN1D. As a typical member of the ENaC/Degenerin superfamily, each of the subunits consists of two transmembrane helices and an extracellular loop.

Function:
ENaC is located in the apical membrane of polarized epithelial cells in particular in the kidney (primarily in the distal tubule), the lung, and the colon facilitating Na⁺ reabsorption across the apical membranes of epithelial cells.