title: Differential involvement of Src family kinases in Fc gamma receptor-mediated phagocytosis.
abstract: The tyrosine phosphorylation cascade originated from Fc gamma receptors (Fc gamma Rs) is essential for macrophage functions including phagocytosis. Although the initial step is ascribed to Src family tyrosine kinases, the role of individual kinases in phagocytosis signaling is still to be determined. In reconstitution experiments, we first showed that expression in the RAW 264.7 cell line of C-terminal Src kinase (Csk) inhibited and that of a membrane-anchored, gain-of-function Csk abolished the Fc gamma R-mediated signaling that leads to phagocytosis in a kinase-dependent manner. We next tested reconstruction of the signaling in the membrane-anchored, gain-of-function Csk-expressing cells by introducing Src family kinases the C-terminal negative regulatory sequence of which was replaced with a c-myc epitope. Those constructs derived from Lyn and Hck (a-Lyn and a-Hck) that associated with detergent-resistant membranes successfully reconstructed Fc gamma R-mediated Syk activation, filamentous actin rearrangement, and phagocytosis. In contrast, c-Src-derived construct (a-Src), that was excluded from detergent-resistant membranes, could not restore the series of phagocytosis signaling. Tyrosine phosphorylation of Vav and c-Cbl was restored in common by a-Lyn, a-Hck, and a-Src, but Fc gamma RIIB tyrosine phosphorylation, which is implicated in negative signaling, was reconstituted solely by a-Lyn and a-Hck. These findings suggest that Src family kinases are differentially involved in Fc gamma R-signaling and that selective kinases including Lyn and Hck are able to fully transduce phagocytotic signaling.
authors.affiliation: Department of Allergy and Rheumatology, University of Tokyo, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Suzuki
authors.forename: H
authors.initials: H
authors.lastname: Kono
authors.forename: N
authors.initials: N
authors.lastname: Hirose
authors.forename: M
authors.initials: M
authors.lastname: Okada
authors.forename: T
authors.initials: T
authors.lastname: Yamamoto
authors.forename: K
authors.initials: K
authors.lastname: Yamamoto
authors.forename: Z
authors.initials: Z
authors.lastname: Honda
mesh_terms: D000199:Actins / Q000378:metabolism; D000595:Amino Acid Sequence; D000818:Animals; D000081247:CSK Tyrosine-Protein Kinase; D002460:Cell Line; D003902:Detergents; D004789:Enzyme Activation / Q000276:immunology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D004792:Enzyme Precursors / Q000037:antagonists & inhibitors / Q000378:metabolism; D004926:Escherichia coli / Q000276:immunology; D006801:Humans; D007166:Immunosuppressive Agents / Q000494:pharmacology; D047908:Intracellular Signaling Peptides and Proteins; D008264:Macrophages / Q000201:enzymology / Q000276:immunology / Q000378:metabolism / Q000382:microbiology; D008563:Membrane Lipids / Q000378:metabolism; D008565:Membrane Proteins / Q000235:genetics / Q000276:immunology; D051379:Mice; D008969:Molecular Sequence Data; D017830:Octoxynol; D009895:Opsonin Proteins / Q000276:immunology / Q000378:metabolism; D010587:Phagocytosis / Q000235:genetics / Q000276:immunology*; D010766:Phosphorylation; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors / Q000096:biosynthesis / Q000172:deficiency / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology / Q000502:physiology; D011518:Proto-Oncogene Proteins / Q000096:biosynthesis / Q000235:genetics; D051572:Proto-Oncogene Proteins c-hck; D016392:Proto-Oncogene Proteins pp60(c-src) / Q000096:biosynthesis / Q000235:genetics; D017452:Receptors, IgG / Q000037:antagonists & inhibitors / Q000502:physiology*; D013107:Sphingolipids / Q000378:metabolism; D000072377:Syk Kinase; D014443:Tyrosine / Q000378:metabolism; D015054:Zymosan / Q000276:immunology / Q000378:metabolism; D019061:src-Family Kinases / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism / Q000502:physiology*
chemical_list: D000199:Actins; D003902:Detergents; D004791:Enzyme Inhibitors; D004792:Enzyme Precursors; D007166:Immunosuppressive Agents; D047908:Intracellular Signaling Peptides and Proteins; D008563:Membrane Lipids; D008565:Membrane Proteins; D009895:Opsonin Proteins; D011518:Proto-Oncogene Proteins; D017452:Receptors, IgG; D013107:Sphingolipids; D014443:Tyrosine; D017830:Octoxynol; D015054:Zymosan; D011505:Protein-Tyrosine Kinases; D000081247:CSK Tyrosine-Protein Kinase; C496631:HCK protein, human; C496632:Hck protein, mouse; D051572:Proto-Oncogene Proteins c-hck; D016392:Proto-Oncogene Proteins pp60(c-src); C000606896:SYK protein, human; D000072377:Syk Kinase; C000606897:Syk protein, mouse; C060902:lyn protein-tyrosine kinase; D019061:src-Family Kinases; C000631346:CSK protein, human