Cellular and Molecular Life Sciences

, Volume 68, Issue 7, pp 1115–1129 | Cite as

Structure of the gap junction channel and its implications for its biological functions

Review

Abstract

Gap junctions consist of arrays of intercellular channels composed of integral membrane proteins called connexin in vertebrates. Gap junction channels regulate the passage of ions and biological molecules between adjacent cells and, therefore, are critically important in many biological activities, including development, differentiation, neural activity, and immune response. Mutations in connexin genes are associated with several human diseases, such as neurodegenerative disease, skin disease, deafness, and developmental abnormalities. The activity of gap junction channels is regulated by the membrane voltage, intracellular microenvironment, interaction with other proteins, and phosphorylation. Each connexin channel has its own property for conductance and molecular permeability. A number of studies have tried to reveal the molecular architecture of the channel pore that should confer the connexin-specific permeability/selectivity properties and molecular basis for the gating and regulation. In this review, we give an overview of structural studies and describe the structural and functional relationship of gap junction channels.

Keywords

Gap junction Connexin Electron microscopy X-ray diffraction Gating Regulation Permeability Selectivity 

Notes

Acknowledgments

This work was supported in part by grants-in-aid for scientific research (16087101, 16087206, and 21227003), the GCOE program (A-041) from the Ministry of Education, Culture, Sports, Sciences, and Technology of Japan (to T.T.).

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© Springer 2010

Authors and Affiliations

  1. 1.Institute for Protein ResearchOsaka University, OLABBSuitaJapan
  2. 2.Department of Life ScienceUniversity of HyogoAkohJapan
  3. 3.Paul Scherrer InstitutBiology and Chemistry OFLG 101VilligenSwitzerland

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