title: FAK blunts adenosine-homocysteine-induced endothelial cell apoptosis: requirement for PI 3-kinase.
abstract: Treatment of cultured bovine pulmonary endothelial cells (BPAEC) with adenosine (Ado) alone or in combination with homocysteine (Hc) leads to disruption of focal adhesion complexes, caspase-dependent degradation of components of focal adhesion complexes, and subsequent apoptosis. Endothelial cells transiently overexpressing paxillin or p130(Cas) cDNAs underwent Ado-Hc-induced apoptosis to an extent similar to that of cells transfected with vector alone. However, overexpression of focal adhesion kinase (FAK) cDNA blunted Ado-Hc-induced apoptosis. FAK constructs lacking the central catalytic domain or containing a point mutation, rendering the catalytic domain enzymatically inactive, did not provide protection from apoptosis. Constructs containing a mutation in the major autophosphorylation site (tyrosine-397) similarly did not prevent cell death. A FAK mutant in amino acid 395, deficient in phosphatidylinositol 3-kinase (PI 3-kinase) binding, was not able to blunt apoptosis. Finally, overexpression of FAK did not provide protection from apoptosis in the presence of LY-294002, a PI 3-kinase inhibitor. Taken together, these data suggest that the survival signals mediated by overexpression of FAK in response to Ado-Hc-induced apoptosis require a PI 3-kinase-dependent pathway.
authors.affiliation: Pulmonary Vascular Biology Research Laboratory, Providence Veterans Affairs Medical Center, and Department of Medicine, Brown Medical School, Providence, Rhode Island 02908, USA.
authors.forename: Robert E
authors.initials: RE
authors.lastname: Bellas
authors.forename: Elizabeth O
authors.initials: EO
authors.lastname: Harrington
authors.forename: Kerri Lynn
authors.initials: KL
authors.lastname: Sheahan
authors.forename: Julie
authors.initials: J
authors.lastname: Newton
authors.forename: Caroline
authors.initials: C
authors.lastname: Marcus
authors.forename: Sharon
authors.initials: S
authors.lastname: Rounds
mesh_terms: D000241:Adenosine / Q000494:pharmacology; D000818:Animals; D017209:Apoptosis / Q000187:drug effects / Q000502:physiology*; D020134:Catalytic Domain; D002417:Cattle; D002470:Cell Survival / Q000187:drug effects / Q000502:physiology; D002478:Cells, Cultured; D050719:Crk-Associated Substrate Protein; D003598:Cytoskeletal Proteins / Q000235:genetics / Q000378:metabolism; D004730:Endothelium, Vascular / Q000166:cytology / Q000201:enzymology*; D051416:Focal Adhesion Protein-Tyrosine Kinases; D015971:Gene Expression Regulation, Enzymologic; D006710:Homocysteine / Q000494:pharmacology; D051419:Paxillin; D019869:Phosphatidylinositol 3-Kinases / Q000235:genetics / Q000378:metabolism*; D010750:Phosphoproteins / Q000235:genetics / Q000378:metabolism; D011505:Protein-Tyrosine Kinases / Q000235:genetics / Q000378:metabolism*; D011506:Proteins; D011651:Pulmonary Artery / Q000166:cytology / Q000201:enzymology*; D050717:Retinoblastoma-Like Protein p130; D015398:Signal Transduction / Q000502:physiology; D014162:Transfection
chemical_list: D050719:Crk-Associated Substrate Protein; D003598:Cytoskeletal Proteins; D051419:Paxillin; D010750:Phosphoproteins; D011506:Proteins; D050717:Retinoblastoma-Like Protein p130; D006710:Homocysteine; D019869:Phosphatidylinositol 3-Kinases; D011505:Protein-Tyrosine Kinases; D051416:Focal Adhesion Protein-Tyrosine Kinases; D000241:Adenosine