Molecular mechanism of intestinal permeability: interaction at tight junctions.
The intestinal barrier plays a critical role in humans in the transport of nutrients and macromolecules. At the same time, it has to provide an effective barrier to harmful macromolecules and microorganisms. The tight junction (TJ) is an essential component of this barrier. The junctional complexes of the plasma membrane are not simply epithelial barriers in paracellular transport or barriers preventing diffusion in the plasma membrane, but also contain proteins involved in signal transduction and the maintenance of the physiological epithelial cell state. Occludin, claudin, junctional adhesion molecules, and the coxsackie virus and adenovirus receptor are the major components of TJs. This article highlights the structure and function of TJs as well as the molecular interactions occurring during permeation through TJs.
Hossain
Zakir
Z
Division of Applied Biosciences, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan.
Hirata
Takashi
T
D000818:Animals; D001692:Biological Transport / Q000187:drug effects; D015815:Cell Adhesion Molecules / Q000235:genetics / Q000502:physiology; D002462:Cell Membrane / Q000378:metabolism; D002463:Cell Membrane Permeability / Q000187:drug effects*; D004847:Epithelial Cells / Q000187:drug effects / Q000502:physiology; D005231:Fatty Acids, Unsaturated / Q000494:pharmacology*; D006801:Humans; D007413:Intestinal Mucosa / Q000378:metabolism*; D007422:Intestines / Q000187:drug effects; D062726:Junctional Adhesion Molecules; D008560:Membrane Fluidity; D021962:Membrane Microdomains / Q000378:metabolism; D008565:Membrane Proteins / Q000235:genetics / Q000502:physiology; D019108:Tight Junctions / Q000187:drug effects* / Q000378:metabolism / Q000502:physiology*
D015815:Cell Adhesion Molecules; D005231:Fatty Acids, Unsaturated; D062726:Junctional Adhesion Molecules; D008565:Membrane Proteins