gap junction


gap junction
gap junction n an area of contact between adjacent cells characterized by modification of the plasma membranes for intercellular communication or transfer of low molecular-weight substances
gap-junc·tion·al 'gap-.jəŋk-shən-əl, -shnəl adj

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a type of intercellular junction comprising a narrowed portion (about 3 nm) of the intercellular space that contains channels or pores (about 2 nm) composed of hexagonal arrays of membrane-spanning proteins around a central lumen (connexon) through which pass ions and small molecules such as most sugars, amino acids, nucleotides, vitamins, hormones, and cyclic AMP. In electrically excitable tissues, these gap junctions serve to transmit electrical impulses via ionic currents and are known as electrotonic synapses; they are present in such tissues as myocardial tissue and the central nervous system. Called also nexus.

Gap junctions providing passageways between the interiors of adjacent cells. Each gap junction consists of two connexons stacked end-to-end, spanning the gap between the membranes, with each connexon comprising six protein subunits arranged around a central channel.


Medical dictionary. 2011.

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  • Gap junction — Gap Junctions Gap Junctions, Zell Zell Kanäle, (lat. Nexus) sind kanalbildende Proteinkomplexe, welche die zytoplasmatischen Kompartimente benachbarter Zellen direkt miteinander verbinden und die Membrane der Zellen in einem bestimmten Abstand… …   Deutsch Wikipedia

  • Gap junction — A gap junction or nexus is a specialized intercellular connection between certain animal cell types. It directly connects the cytoplasm of two cells, which allows various molecules and ions to pass freely between cells.One gap junction is… …   Wikipedia

  • Gap Junction — Übergeordnet Zell Zell Kontakt Untergeordnet Connexon Pannexon …   Deutsch Wikipedia

  • gap junction — noun : an area of contact between adjacent cells characterized by modification of the plasma membranes for intercellular communication or transfer of low molecular weight substances • gap junctional ¦ ̷ ̷ ¦ ̷ ̷  ̷ ̷  ̷ ̷ adjective * * * Cell Biol …   Useful english dictionary

  • gap junction — gap′ junc tion n. cbl Biol. a structure consisting of a series of channels extending across the gap between two cells, allowing the passage of ions, small molecules, etc …   From formal English to slang

  • gap junction — A junction between two cells consisting of many pores that allow the passage of molecules up to about 900 D. Each pore is formed by an hexagonal array (connexon) of six transmembrane proteins (connexins) in each plasma membrane: when mated… …   Dictionary of molecular biology

  • gap junction — Cell Biol. a linkage of two adjacent cells consisting of a system of channels extending across a gap from one cell to the other, allowing the passage of ions and small molecules. * * * …   Universalium

  • gap junction — noun Date: 1967 an area of contact between adjacent cells characterized by modification of the plasma membranes for intercellular communication or transfer of low molecular weight substances …   New Collegiate Dictionary

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