Direct binding of three tight junction-associated MAGUKs, ZO-1, ZO-2, and ZO-3, with the COOH termini of claudins

J Cell Biol. 1999 Dec 13;147(6):1351-63. doi: 10.1083/jcb.147.6.1351.

Abstract

ZO-1, ZO-2, and ZO-3, which contain three PDZ domains (PDZ1 to -3), are concentrated at tight junctions (TJs) in epithelial cells. TJ strands are mainly composed of two distinct types of four-transmembrane proteins, occludin, and claudins, between which occludin was reported to directly bind to ZO-1/ZO-2/ZO-3. However, in occludin-deficient intestinal epithelial cells, ZO-1/ZO-2/ZO-3 were still recruited to TJs. We then examined the possible interactions between ZO-1/ZO-2/ZO-3 and claudins. ZO-1, ZO-2, and ZO-3 bound to the COOH-terminal YV sequence of claudin-1 to -8 through their PDZ1 domains in vitro. Then, claudin-1 or -2 was transfected into L fibroblasts, which express ZO-1 but not ZO-2 or ZO-3. Claudin-1 and -2 were concentrated at cell-cell borders in an elaborate network pattern, to which endogenous ZO-1 was recruited. When ZO-2 or ZO-3 were further transfected, both were recruited to the claudin-based networks together with endogenous ZO-1. Detailed analyses showed that ZO-2 and ZO-3 are recruited to the claudin-based networks through PDZ2 (ZO-2 or ZO-3)/PDZ2 (endogenous ZO-1) and PDZ1 (ZO-2 or ZO-3)/COOH-terminal YV (claudins) interactions. In good agreement, PDZ1 and PDZ2 domains of ZO-1/ZO-2/ZO-3 were also recruited to claudin-based TJs, when introduced into cultured epithelial cells. The possible molecular architecture of TJ plaque structures is discussed.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Motifs
  • Amino Acid Sequence
  • Animals
  • Carrier Proteins / chemistry
  • Carrier Proteins / genetics
  • Carrier Proteins / metabolism*
  • Cells, Cultured
  • Claudin-1
  • Claudins
  • Epithelial Cells / cytology
  • Gene Deletion
  • Intestines / cytology
  • L Cells
  • Membrane Proteins / chemistry
  • Membrane Proteins / deficiency
  • Membrane Proteins / genetics
  • Membrane Proteins / metabolism*
  • Mice
  • Mice, Knockout
  • Models, Biological
  • Occludin
  • Phosphoproteins / chemistry
  • Phosphoproteins / genetics
  • Phosphoproteins / metabolism*
  • Protein Binding
  • Recombinant Fusion Proteins / chemistry
  • Recombinant Fusion Proteins / genetics
  • Recombinant Fusion Proteins / metabolism
  • Tight Junctions / chemistry
  • Tight Junctions / metabolism*
  • Transfection
  • Zonula Occludens Proteins
  • Zonula Occludens-1 Protein
  • Zonula Occludens-2 Protein

Substances

  • CLDN1 protein, human
  • CLDN2 protein, human
  • Carrier Proteins
  • Claudin-1
  • Claudins
  • Cldn1 protein, mouse
  • Cldn2 protein, mouse
  • Membrane Proteins
  • OCLN protein, human
  • Occludin
  • Ocln protein, mouse
  • Phosphoproteins
  • Recombinant Fusion Proteins
  • TJP1 protein, human
  • TJP2 protein, human
  • Tjp1 protein, mouse
  • Tjp2 protein, mouse
  • Tjp3 protein, mouse
  • Zonula Occludens Proteins
  • Zonula Occludens-1 Protein
  • Zonula Occludens-2 Protein

Associated data

  • GENBANK/AF157006