title: Chemical anoxia of tubular cells induces activation of c-Src and its translocation to the zonula adherens.
abstract: Cyanide (CN)-induced chemical anoxia of cultured mouse proximal tubular (MPT) cells increased the kinase activity of c-Src by approximately threefold. 4-Amino-5-(4-chlorophenyl)-7-(t-butyl)pyrazolo[3,4-d]pyrimidine (PP2), a specific inhibitor of c-Src, prevented Src activation. CN also increased the permeability of MPT cell monolayers, an event ameliorated by PP2. During CN treatment, the proteins of the zonula adherens (ZA; E-cadherin and the catenins) disappeared from their normal location at cell-cell borders and appeared within the cytosol. CN also resulted in the appearance of c-Src at cell-cell borders. PP2 prevented these CN-induced alterations in the distribution of ZA proteins and c-Src. CN also increased the association of c-Src with beta-catenin and p120 and induced a substantial increase in tyrosine phosphorylation of both catenins. PP2 prevented the CN-induced phosphorylation of these catenins. In summary, we show that CN-induced chemical anoxia activates c-Src and induces its translocation to cell-cell junctions where it binds to and phosphorylates beta-catenin and p120. Our findings suggest that these events contribute to the loss of the epithelial barrier function associated with chemical anoxia.
authors.affiliation: Renal Section, Evans Biomedical Research Center, Department of Medicine, Boston Medical Center and Boston University School of Medicine, Boston, Massachusetts 02118, USA.
authors.forename: Diviya
authors.initials: D
authors.lastname: Sinha
authors.forename: Zhiyong
authors.initials: Z
authors.lastname: Wang
authors.forename: Valerie R
authors.initials: VR
authors.lastname: Price
authors.forename: John H
authors.initials: JH
authors.lastname: Schwartz
authors.forename: Wilfred
authors.initials: W
authors.lastname: Lieberthal
mesh_terms: D000199:Actins / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000378:metabolism; D022005:Adherens Junctions / Q000378:metabolism*; D000818:Animals; D000081247:CSK Tyrosine-Protein Kinase; D015820:Cadherins / Q000378:metabolism; D051177:Catenins; D015815:Cell Adhesion Molecules / Q000378:metabolism; D015687:Cell Hypoxia / Q000187:drug effects / Q000502:physiology; D002460:Cell Line; D003598:Cytoskeletal Proteins / Q000378:metabolism; D004789:Enzyme Activation / Q000187:drug effects; D004791:Enzyme Inhibitors / Q000494:pharmacology; D051417:Focal Adhesion Kinase 1; D051416:Focal Adhesion Protein-Tyrosine Kinases; D007687:Kidney Tubules, Proximal / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D051379:Mice; D008822:Mice, Transgenic; D010539:Permeability / Q000187:drug effects; D010750:Phosphoproteins / Q000378:metabolism; D010766:Phosphorylation / Q000187:drug effects; D021381:Protein Transport / Q000187:drug effects; D011505:Protein-Tyrosine Kinases; D016392:Proto-Oncogene Proteins pp60(c-src) / Q000378:metabolism*; D011743:Pyrimidines / Q000494:pharmacology; D012966:Sodium Cyanide / Q000494:pharmacology; D015534:Trans-Activators / Q000378:metabolism; D051176:beta Catenin; D019061:src-Family Kinases; D000095002:Delta Catenin
chemical_list: C412373:AG 1879; D000199:Actins; C495267:CTNNB1 protein, mouse; D015820:Cadherins; D051177:Catenins; D015815:Cell Adhesion Molecules; D003598:Cytoskeletal Proteins; D004791:Enzyme Inhibitors; D010750:Phosphoproteins; D011743:Pyrimidines; D015534:Trans-Activators; D051176:beta Catenin; D000255:Adenosine Triphosphate; D011505:Protein-Tyrosine Kinases; D000081247:CSK Tyrosine-Protein Kinase; D051417:Focal Adhesion Kinase 1; D051416:Focal Adhesion Protein-Tyrosine Kinases; D016392:Proto-Oncogene Proteins pp60(c-src); C496051:Ptk2 protein, mouse; D019061:src-Family Kinases; D012966:Sodium Cyanide; D000095002:Delta Catenin