Involvement of pp125FAK and p60SRC in the signaling through Fc gamma RII-Fc gamma RIII in murine macrophages.
Cross-linking the FcgammaRs can activate a wide variety of biological responses in macrophages. Receptor stimulation induces activation of protein tyrosine kinase cascades that result in phagocytosis, a process known to involve cytoskeletal rearrangements. Therefore, an involvement of non-receptor tyrosine kinases such as pp125FAK, in FcgammaR signaling is likely. Using the murine macrophage cell line J774, we demonstrate that FcgammaRII-RIII cross-linking induces a time- and dose-dependent increase in tyrosine phosphorylation of the focal adhesion kinase pp125FAK that correlates with an increase in its catalytic activity. Interestingly enough, pp125FAK activation results in its association both to the FcgammaRII-III and to p60Src. The results presented here define a novel-signaling pathway likely to be important in low affinity FcgammaRII-III mediated phagocytosis.
Antonieta Cote-Vélez
M J
MJ
Departamento de Genética y Biología Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Apartado Postal 14-740, D.F. 07000, Mexico, Mexico.
Ortega
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Ortega
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D000818:Animals; D002460:Cell Line; D003432:Cross-Linking Reagents / Q000378:metabolism; D004791:Enzyme Inhibitors / Q000494:pharmacology; D051417:Focal Adhesion Kinase 1; D051416:Focal Adhesion Protein-Tyrosine Kinases; D019833:Genistein / Q000494:pharmacology; D008024:Ligands; D008264:Macrophages / Q000201:enzymology / Q000378:metabolism*; D051379:Mice; D010766:Phosphorylation / Q000187:drug effects; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors / Q000502:physiology*; D016392:Proto-Oncogene Proteins pp60(c-src) / Q000502:physiology*; D017452:Receptors, IgG / Q000378:metabolism / Q000502:physiology*; D015398:Signal Transduction / Q000276:immunology*; D014443:Tyrosine / Q000378:metabolism
D003432:Cross-Linking Reagents; D004791:Enzyme Inhibitors; D008024:Ligands; D017452:Receptors, IgG; D014443:Tyrosine; D019833:Genistein; D011505:Protein-Tyrosine Kinases; D051417:Focal Adhesion Kinase 1; D051416:Focal Adhesion Protein-Tyrosine Kinases; D016392:Proto-Oncogene Proteins pp60(c-src); C496051:Ptk2 protein, mouse