Gap junctions

Cold Spring Harb Perspect Biol. 2009 Jul;1(1):a002576. doi: 10.1101/cshperspect.a002576.


Gap junctions are aggregates of intercellular channels that permit direct cell-cell transfer of ions and small molecules. Initially described as low-resistance ion pathways joining excitable cells (nerve and muscle), gap junctions are found joining virtually all cells in solid tissues. Their long evolutionary history has permitted adaptation of gap-junctional intercellular communication to a variety of functions, with multiple regulatory mechanisms. Gap-junctional channels are composed of hexamers of medium-sized families of integral proteins: connexins in chordates and innexins in precordates. The functions of gap junctions have been explored by studying mutations in flies, worms, and humans, and targeted gene disruption in mice. These studies have revealed a wide diversity of function in tissue and organ biology.

Publication types

  • Research Support, N.I.H., Extramural
  • Review

MeSH terms

  • Animals
  • Central Nervous System / metabolism
  • Connexins / metabolism*
  • Gap Junctions / metabolism
  • Gap Junctions / physiology*
  • Gene Expression Regulation, Developmental*
  • Hepatocytes / cytology
  • Humans
  • Lens, Crystalline / metabolism
  • Mice
  • Models, Biological
  • Myelin Sheath / metabolism
  • Recombinant Proteins / metabolism
  • X-Ray Diffraction


  • Connexins
  • Recombinant Proteins