Abstract
It is known that beta 2 integrins are crucial for leukocyte cell-cell and cell-matrix interactions, and accumulating evidence now suggests that integrins serve not only as a structural link but also as a signal-transducing unit that controls adhesion-induced changes in cell functions. In the present study, we plated human neutrophils on surface-bound anti-beta 2 (CD18) antibodies and found that the small GTP-binding protein p21ras is activated by beta 2 integrins. Pretreatment of the cells with genistein, a tyrosine kinase inhibitor, led to a complete block of p21ras activation, an effect that was not achieved with either U73122, which abolishes the beta 2 integrin-induced Ca2+ signal, or wortmannin, which totally inhibits the phosphatidylinositol 3-kinase activity. Western blot analysis revealed that antibody-induced engagement of beta 2 integrins causes tyrosine phosphorylation of several proteins in the cells. One of these tyrosine-phosphorylated proteins had an apparent molecular mass of 95 kDa and was identified as the protooncogene product Vav, a p21ras guanine nucleotide exchange factor that is specifically expressed in cells of hematopoietic lineage. A role for Vav in the activation of p21ras is supported by the observations that antibody-induced engagement of beta 2 integrins causes an association of Vav with p21ras and that the effect of genistein on p21ras activation coincided with its ability to inhibit both the tyrosine phosphorylation of Vav and the Vav-p21ras association. Taken together, these results indicate that antibody-induced engagement of beta 2 integrins on neutrophils triggers tyrosine phosphorylation of Vav and, possibly through its association, a downstream activation of p21ras.
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- Akiyama T., Ishida J., Nakagawa S., Ogawara H., Watanabe S., Itoh N., Shibuya M., Fukami Y. Genistein, a specific inhibitor of tyrosine-specific protein kinases. J Biol Chem. 1987 Apr 25;262(12):5592–5595. [PubMed] [Google Scholar]
- Alai M., Mui A. L., Cutler R. L., Bustelo X. R., Barbacid M., Krystal G. Steel factor stimulates the tyrosine phosphorylation of the proto-oncogene product, p95vav, in human hemopoietic cells. J Biol Chem. 1992 Sep 5;267(25):18021–18025. [PubMed] [Google Scholar]
- Arcaro A., Wymann M. P. Wortmannin is a potent phosphatidylinositol 3-kinase inhibitor: the role of phosphatidylinositol 3,4,5-trisphosphate in neutrophil responses. Biochem J. 1993 Dec 1;296(Pt 2):297–301. doi: 10.1042/bj2960297. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Berton G., Fumagalli L., Laudanna C., Sorio C. Beta 2 integrin-dependent protein tyrosine phosphorylation and activation of the FGR protein tyrosine kinase in human neutrophils. J Cell Biol. 1994 Aug;126(4):1111–1121. doi: 10.1083/jcb.126.4.1111. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Berton G., Laudanna C., Sorio C., Rossi F. Generation of signals activating neutrophil functions by leukocyte integrins: LFA-1 and gp150/95, but not CR3, are able to stimulate the respiratory burst of human neutrophils. J Cell Biol. 1992 Feb;116(4):1007–1017. doi: 10.1083/jcb.116.4.1007. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Bleasdale J. E., Thakur N. R., Gremban R. S., Bundy G. L., Fitzpatrick F. A., Smith R. J., Bunting S. Selective inhibition of receptor-coupled phospholipase C-dependent processes in human platelets and polymorphonuclear neutrophils. J Pharmacol Exp Ther. 1990 Nov;255(2):756–768. [PubMed] [Google Scholar]
- Boguski M. S., McCormick F. Proteins regulating Ras and its relatives. Nature. 1993 Dec 16;366(6456):643–654. doi: 10.1038/366643a0. [DOI] [PubMed] [Google Scholar]
- Bokoch G. M., Der C. J. Emerging concepts in the Ras superfamily of GTP-binding proteins. FASEB J. 1993 Jun;7(9):750–759. doi: 10.1096/fasebj.7.9.8330683. [DOI] [PubMed] [Google Scholar]
- Buday L., Egan S. E., Rodriguez Viciana P., Cantrell D. A., Downward J. A complex of Grb2 adaptor protein, Sos exchange factor, and a 36-kDa membrane-bound tyrosine phosphoprotein is implicated in ras activation in T cells. J Biol Chem. 1994 Mar 25;269(12):9019–9023. [PubMed] [Google Scholar]
- Bustelo X. R., Barbacid M. Tyrosine phosphorylation of the vav proto-oncogene product in activated B cells. Science. 1992 May 22;256(5060):1196–1199. doi: 10.1126/science.256.5060.1196. [DOI] [PubMed] [Google Scholar]
- Böyum A. Isolation of mononuclear cells and granulocytes from human blood. Isolation of monuclear cells by one centrifugation, and of granulocytes by combining centrifugation and sedimentation at 1 g. Scand J Clin Lab Invest Suppl. 1968;97:77–89. [PubMed] [Google Scholar]
- Carlos T. M., Harlan J. M. Leukocyte-endothelial adhesion molecules. Blood. 1994 Oct 1;84(7):2068–2101. [PubMed] [Google Scholar]
- Clark E. A., Brugge J. S. Integrins and signal transduction pathways: the road taken. Science. 1995 Apr 14;268(5208):233–239. doi: 10.1126/science.7716514. [DOI] [PubMed] [Google Scholar]
- Cross M. J., Stewart A., Hodgkin M. N., Kerr D. J., Wakelam M. J. Wortmannin and its structural analogue demethoxyviridin inhibit stimulated phospholipase A2 activity in Swiss 3T3 cells. Wortmannin is not a specific inhibitor of phosphatidylinositol 3-kinase. J Biol Chem. 1995 Oct 27;270(43):25352–25355. doi: 10.1074/jbc.270.43.25352. [DOI] [PubMed] [Google Scholar]
- Diamond M. S., Springer T. A. The dynamic regulation of integrin adhesiveness. Curr Biol. 1994 Jun 1;4(6):506–517. doi: 10.1016/s0960-9822(00)00111-1. [DOI] [PubMed] [Google Scholar]
- Dustin M. L., Springer T. A. Lymphocyte function-associated antigen-1 (LFA-1) interaction with intercellular adhesion molecule-1 (ICAM-1) is one of at least three mechanisms for lymphocyte adhesion to cultured endothelial cells. J Cell Biol. 1988 Jul;107(1):321–331. doi: 10.1083/jcb.107.1.321. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Farnsworth C. L., Freshney N. W., Rosen L. B., Ghosh A., Greenberg M. E., Feig L. A. Calcium activation of Ras mediated by neuronal exchange factor Ras-GRF. Nature. 1995 Aug 10;376(6540):524–527. doi: 10.1038/376524a0. [DOI] [PubMed] [Google Scholar]
- Fuortes M., Jin W. W., Nathan C. Adhesion-dependent protein tyrosine phosphorylation in neutrophils treated with tumor necrosis factor. J Cell Biol. 1993 Feb;120(3):777–784. doi: 10.1083/jcb.120.3.777. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Fuortes M., Jin W. W., Nathan C. Beta 2 integrin-dependent tyrosine phosphorylation of paxillin in human neutrophils treated with tumor necrosis factor. J Cell Biol. 1994 Dec;127(5):1477–1483. doi: 10.1083/jcb.127.5.1477. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Fuortes M., Jin W. W., Nathan C. Beta 2 integrin-dependent tyrosine phosphorylation of paxillin in human neutrophils treated with tumor necrosis factor. J Cell Biol. 1994 Dec;127(5):1477–1483. doi: 10.1083/jcb.127.5.1477. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Fällman M., Andersson R., Andersson T. Signaling properties of CR3 (CD11b/CD18) and CR1 (CD35) in relation to phagocytosis of complement-opsonized particles. J Immunol. 1993 Jul 1;151(1):330–338. [PubMed] [Google Scholar]
- Fällman M., Gullberg M., Hellberg C., Andersson T. Complement receptor-mediated phagocytosis is associated with accumulation of phosphatidylcholine-derived diglyceride in human neutrophils. Involvement of phospholipase D and direct evidence for a positive feedback signal of protein kinase. J Biol Chem. 1992 Feb 5;267(4):2656–2663. [PubMed] [Google Scholar]
- Geng Y., Gulbins E., Altman A., Lotz M. Monocyte deactivation by interleukin 10 via inhibition of tyrosine kinase activity and the Ras signaling pathway. Proc Natl Acad Sci U S A. 1994 Aug 30;91(18):8602–8606. doi: 10.1073/pnas.91.18.8602. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Gibbs J. B., Marshall M. S., Scolnick E. M., Dixon R. A., Vogel U. S. Modulation of guanine nucleotides bound to Ras in NIH3T3 cells by oncogenes, growth factors, and the GTPase activating protein (GAP). J Biol Chem. 1990 Nov 25;265(33):20437–20442. [PubMed] [Google Scholar]
- Gulbins E., Coggeshall K. M., Baier G., Katzav S., Burn P., Altman A. Tyrosine kinase-stimulated guanine nucleotide exchange activity of Vav in T cell activation. Science. 1993 May 7;260(5109):822–825. doi: 10.1126/science.8484124. [DOI] [PubMed] [Google Scholar]
- Gulbins E., Schlottmann K., Brenner B., Lang F., Coggeshall K. M. Molecular analysis of Ras activation by tyrosine phosphorylated Vav. Biochem Biophys Res Commun. 1995 Dec 26;217(3):876–885. doi: 10.1006/bbrc.1995.2853. [DOI] [PubMed] [Google Scholar]
- Hall A. Small GTP-binding proteins and the regulation of the actin cytoskeleton. Annu Rev Cell Biol. 1994;10:31–54. doi: 10.1146/annurev.cb.10.110194.000335. [DOI] [PubMed] [Google Scholar]
- Jaconi M. E., Theler J. M., Schlegel W., Appel R. D., Wright S. D., Lew P. D. Multiple elevations of cytosolic-free Ca2+ in human neutrophils: initiation by adherence receptors of the integrin family. J Cell Biol. 1991 Mar;112(6):1249–1257. doi: 10.1083/jcb.112.6.1249. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Joneson T., White M. A., Wigler M. H., Bar-Sagi D. Stimulation of membrane ruffling and MAP kinase activation by distinct effectors of RAS. Science. 1996 Feb 9;271(5250):810–812. doi: 10.1126/science.271.5250.810. [DOI] [PubMed] [Google Scholar]
- Kapron-Bras C., Fitz-Gibbon L., Jeevaratnam P., Wilkins J., Dedhar S. Stimulation of tyrosine phosphorylation and accumulation of GTP-bound p21ras upon antibody-mediated alpha 2 beta 1 integrin activation in T-lymphoblastic cells. J Biol Chem. 1993 Oct 5;268(28):20701–20704. [PubMed] [Google Scholar]
- Katzav S., Cleveland J. L., Heslop H. E., Pulido D. Loss of the amino-terminal helix-loop-helix domain of the vav proto-oncogene activates its transforming potential. Mol Cell Biol. 1991 Apr;11(4):1912–1920. doi: 10.1128/mcb.11.4.1912. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Laemmli U. K. Cleavage of structural proteins during the assembly of the head of bacteriophage T4. Nature. 1970 Aug 15;227(5259):680–685. doi: 10.1038/227680a0. [DOI] [PubMed] [Google Scholar]
- Lahesmaa R., Allsup A., Soderberg C., Jackman J., Findell P., Peltz G. Modulation of the Grb2-associated protein complex in human CD4+ T cells by receptor activation. J Immunol. 1995 Oct 15;155(8):3815–3822. [PubMed] [Google Scholar]
- Laudanna C., Campbell J. J., Butcher E. C. Role of Rho in chemoattractant-activated leukocyte adhesion through integrins. Science. 1996 Feb 16;271(5251):981–983. doi: 10.1126/science.271.5251.981. [DOI] [PubMed] [Google Scholar]
- Laudanna C., Rossi F., Berton G. Effect of inhibitors of distinct signalling pathways on neutrophil Q2- generation in response to tumor necrosis factor-alpha, and antibodies against CD18 and CD11a: evidence for a common and unique pattern of sensitivity to wortmannin and protein tyrosine kinase inhibitors. Biochem Biophys Res Commun. 1993 Feb 15;190(3):935–940. doi: 10.1006/bbrc.1993.1139. [DOI] [PubMed] [Google Scholar]
- Löfgren R., Ng-Sikorski J., Sjölander A., Andersson T. Beta 2 integrin engagement triggers actin polymerization and phosphatidylinositol trisphosphate formation in non-adherent human neutrophils. J Cell Biol. 1993 Dec;123(6 Pt 1):1597–1605. doi: 10.1083/jcb.123.6.1597. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Margolis B., Hu P., Katzav S., Li W., Oliver J. M., Ullrich A., Weiss A., Schlessinger J. Tyrosine phosphorylation of vav proto-oncogene product containing SH2 domain and transcription factor motifs. Nature. 1992 Mar 5;356(6364):71–74. doi: 10.1038/356071a0. [DOI] [PubMed] [Google Scholar]
- Marshall M. S. Ras target proteins in eukaryotic cells. FASEB J. 1995 Oct;9(13):1311–1318. doi: 10.1096/fasebj.9.13.7557021. [DOI] [PubMed] [Google Scholar]
- Motto D. G., Ross S. E., Jackman J. K., Sun Q., Olson A. L., Findell P. R., Koretzky G. A. In vivo association of Grb2 with pp116, a substrate of the T cell antigen receptor-activated protein tyrosine kinase. J Biol Chem. 1994 Aug 26;269(34):21608–21613. [PubMed] [Google Scholar]
- Pawson T. Protein modules and signalling networks. Nature. 1995 Feb 16;373(6515):573–580. doi: 10.1038/373573a0. [DOI] [PubMed] [Google Scholar]
- Philips M. R., Pillinger M. H., Staud R., Volker C., Rosenfeld M. G., Weissmann G., Stock J. B. Carboxyl methylation of Ras-related proteins during signal transduction in neutrophils. Science. 1993 Feb 12;259(5097):977–980. doi: 10.1126/science.8438158. [DOI] [PubMed] [Google Scholar]
- Rafiee P., Lee J. K., Leung C. C., Raffin T. A. TNF-alpha induces tyrosine phosphorylation of mitogen-activated protein kinase in adherent human neutrophils. J Immunol. 1995 May 1;154(9):4785–4792. [PubMed] [Google Scholar]
- Richter J., Ng-Sikorski J., Olsson I., Andersson T. Tumor necrosis factor-induced degranulation in adherent human neutrophils is dependent on CD11b/CD18-integrin-triggered oscillations of cytosolic free Ca2+. Proc Natl Acad Sci U S A. 1990 Dec;87(23):9472–9476. doi: 10.1073/pnas.87.23.9472. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Ridley A. J., Paterson H. F., Johnston C. L., Diekmann D., Hall A. The small GTP-binding protein rac regulates growth factor-induced membrane ruffling. Cell. 1992 Aug 7;70(3):401–410. doi: 10.1016/0092-8674(92)90164-8. [DOI] [PubMed] [Google Scholar]
- Rodriguez-Viciana P., Warne P. H., Dhand R., Vanhaesebroeck B., Gout I., Fry M. J., Waterfield M. D., Downward J. Phosphatidylinositol-3-OH kinase as a direct target of Ras. Nature. 1994 Aug 18;370(6490):527–532. doi: 10.1038/370527a0. [DOI] [PubMed] [Google Scholar]
- Sanchez-Madrid F., Nagy J. A., Robbins E., Simon P., Springer T. A. A human leukocyte differentiation antigen family with distinct alpha-subunits and a common beta-subunit: the lymphocyte function-associated antigen (LFA-1), the C3bi complement receptor (OKM1/Mac-1), and the p150,95 molecule. J Exp Med. 1983 Dec 1;158(6):1785–1803. doi: 10.1084/jem.158.6.1785. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Schlaepfer D. D., Hanks S. K., Hunter T., van der Geer P. Integrin-mediated signal transduction linked to Ras pathway by GRB2 binding to focal adhesion kinase. Nature. 1994 Dec 22;372(6508):786–791. doi: 10.1038/372786a0. [DOI] [PubMed] [Google Scholar]
- Sjölander A., Yamamoto K., Huber B. E., Lapetina E. G. Association of p21ras with phosphatidylinositol 3-kinase. Proc Natl Acad Sci U S A. 1991 Sep 15;88(18):7908–7912. doi: 10.1073/pnas.88.18.7908. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Springer T. A. Adhesion receptors of the immune system. Nature. 1990 Aug 2;346(6283):425–434. doi: 10.1038/346425a0. [DOI] [PubMed] [Google Scholar]
- Stephens L., Smrcka A., Cooke F. T., Jackson T. R., Sternweis P. C., Hawkins P. T. A novel phosphoinositide 3 kinase activity in myeloid-derived cells is activated by G protein beta gamma subunits. Cell. 1994 Apr 8;77(1):83–93. doi: 10.1016/0092-8674(94)90237-2. [DOI] [PubMed] [Google Scholar]
- Särndahl E., Bokoch G. M., Stendahl O., Andersson T. Stimulus-induced dissociation of alpha subunits of heterotrimeric GTP-binding proteins from the cytoskeleton of human neutrophils. Proc Natl Acad Sci U S A. 1993 Jul 15;90(14):6552–6556. doi: 10.1073/pnas.90.14.6552. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Touhara K., Hawes B. E., van Biesen T., Lefkowitz R. J. G protein beta gamma subunits stimulate phosphorylation of Shc adapter protein. Proc Natl Acad Sci U S A. 1995 Sep 26;92(20):9284–9287. doi: 10.1073/pnas.92.20.9284. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Towbin H., Staehelin T., Gordon J. Electrophoretic transfer of proteins from polyacrylamide gels to nitrocellulose sheets: procedure and some applications. Proc Natl Acad Sci U S A. 1979 Sep;76(9):4350–4354. doi: 10.1073/pnas.76.9.4350. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Umezawa K., Hori T., Tajima H., Imoto M., Isshiki K., Takeuchi T. Inhibition of epidermal growth factor-induced DNA synthesis by tyrosine kinase inhibitors. FEBS Lett. 1990 Jan 29;260(2):198–200. doi: 10.1016/0014-5793(90)80102-o. [DOI] [PubMed] [Google Scholar]
- Worthen G. S., Avdi N., Buhl A. M., Suzuki N., Johnson G. L. FMLP activates Ras and Raf in human neutrophils. Potential role in activation of MAP kinase. J Clin Invest. 1994 Aug;94(2):815–823. doi: 10.1172/JCI117401. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Wright S. D., Rao P. E., Van Voorhis W. C., Craigmyle L. S., Iida K., Talle M. A., Westberg E. F., Goldstein G., Silverstein S. C. Identification of the C3bi receptor of human monocytes and macrophages by using monoclonal antibodies. Proc Natl Acad Sci U S A. 1983 Sep;80(18):5699–5703. doi: 10.1073/pnas.80.18.5699. [DOI] [PMC free article] [PubMed] [Google Scholar]
- van der Geer P., Hunter T., Lindberg R. A. Receptor protein-tyrosine kinases and their signal transduction pathways. Annu Rev Cell Biol. 1994;10:251–337. doi: 10.1146/annurev.cb.10.110194.001343. [DOI] [PubMed] [Google Scholar]