Tyrosine phosphorylation and dissociation of occludin-ZO-1 and E-cadherin-beta-catenin complexes from the cytoskeleton by oxidative stress

• Published in: Biochemical journal 2002-12, Vol.368 (Pt 2), p.471-481
• Main Authors: Rao, Radhakrishna K, Basuroy, Shyamali, Rao, Vijay U, Karnaky, Jr, Karl J, Gupta, Akshay
• Format: Article
• Language: English
• Subjects: beta Catenin; Caco-2 Cells - drug effects; Caco-2 Cells - metabolism; Cadherins - metabolism; Cell Membrane - metabolism; Cytoskeletal Proteins - drug effects; Cytoskeletal Proteins - metabolism; Cytoskeleton - metabolism; Enzyme Inhibitors - pharmacology; Genistein - pharmacology; Humans; Intercellular Junctions - metabolism; Membrane Proteins - metabolism; Occludin; Oxidative Stress; Phosphoproteins - metabolism; Phosphorylation - drug effects; Protein-Tyrosine Kinases - drug effects; Protein-Tyrosine Kinases - metabolism; Trans-Activators - drug effects; Trans-Activators - metabolism; Tyrosine - metabolism; Xanthine - pharmacology; Xanthine Oxidase - pharmacology; Zonula Occludens-1 Protein
• ISSN: 0264-6021; 1470-8728
• DOI: 10.1042/BJ20011804

The oxidative-stress-induced alteration in paracellular junctional complexes was analysed in Caco-2 cell monolayer. Oxidative stress induced a rapid increase in tyrosine phosphorylation of occludin, zonula occludens (ZO)-1, E-cadherin and beta-catenin. An oxidative-stress-induced decrease in transepithelial electrical resistance was associated with a redistribution of occludin-ZO-1 and E-cadherin-beta-catenin complexes from the intercellular junctions. Genistein, a tyrosine kinase inhibitor, prevented the oxidative-stress-induced decrease in resistance and redistribution of protein complexes. Occludin, ZO-1, E-cadherin and beta-catenin in the Triton-insoluble cytoskeletal fraction were reduced by oxidative stress, which was prevented by genistein. Oxidative stress also reduced the co-immunoprecipitation of ZO-1 with occludin, which was prevented by genistein. Co-immunoprecipitation of beta-catenin with E-cadherin was unaffected by oxidative stress or genistein. ZO-1, E-cadherin and beta-catenin in the plasma membrane or membrane-cytoskeleton were either slightly reduced or unaffected by oxidative stress or genistein. These results show that oxidative stress induces tyrosine phosphorylation and cellular redistribution of occludin-ZO-1 and E-cadherin-beta-catenin complexes by a tyrosine-kinase-dependent mechanism.