Functional domains within the degenerin/epithelial sodium channel (Deg/ENaC) superfamily of ion channels

J Physiol. 1999 Nov 1;520 Pt 3(Pt 3):631-44. doi: 10.1111/j.1469-7793.1999.00631.x.


Application of recombinant DNA technology and electrophysiology to the study of amiloride-sensitive Na+ channels has resulted in an enormous increase in the understanding of the structure-function relationships of these channels. Moreover, this knowledge has permitted the elucidation of the physiological roles of these ion channels in cellular processes as diverse as transepithelial salt and water movement, taste perception, volume regulation, nociception, neuronal function, mechanosensation, and even defaecation. Although members of this ever-growing superfamily of ion channels (the Deg/ENaC superfamily) share little amino acid identity, they are all organized similarly, namely, two short N- and C-termini, two short membrane-spanning segments, and a very large extracellular loop domain. In this brief Topical Review, we discuss the structural features of each domain of this Deg/ENaC superfamily and, using ENaC as a model, show how each domain relates to overall channel function.

Publication types

  • Research Support, U.S. Gov't, P.H.S.
  • Review

MeSH terms

  • Amino Acid Sequence / genetics
  • Animals
  • Cytoplasm / metabolism
  • Degenerin Sodium Channels
  • Epithelial Sodium Channels
  • Ion Channels / genetics*
  • Ion Channels / physiology*
  • Molecular Sequence Data
  • Nerve Tissue Proteins / genetics*
  • Nerve Tissue Proteins / physiology*
  • Sodium Channels / genetics*
  • Sodium Channels / physiology*


  • Degenerin Sodium Channels
  • Epithelial Sodium Channels
  • Ion Channels
  • Nerve Tissue Proteins
  • Sodium Channels