Regulation of FynT Function by Dual Domain Docking on PAG/Cbp

Abstract

In resting T-cells, the transmembrane adaptor protein PAG (phosphoprotein associated with glycosphingolipid-enriched microdomains) is constitutively tyrosine-phosphorylated, a state maintained by the Src family kinase FynT. PAG has a role in negative regulation of Src family kinases in T-cells by recruitment of Csk (C-terminal Src kinase) to the membrane via binding to PAG phosphotyrosine 317. The interaction between FynT and PAG is essential for PAG function; however, so far the FynT binding mode has been unknown. Here, we demonstrate that the FynT-PAG complex formation is a dual domain docking process, involving SH2 domain binding to PAG phosphotyrosines as well as an SH3 domain interaction with the first proline-rich region of PAG. This binding mode affects FynT kinase activity, PAG phosphorylation, and recruitment of FynT and Csk, demonstrated in Jurkat TAg cells after antibody stimulation of the T cell receptor. Furthermore, we show that TCR-induced tyrosine phosphorylation is regulated by SH3 domain modulation of the FynT-PAG interaction in human primary T-cells. Although FynT SH3 domain association is shown to be crucial for efficiently initiating PAG phosphorylation, we suggest that engagement of the SH2 domain on PAG renders FynT insensitive to Csk negative regulation. Thus, in T-cells, PAG is involved in positive as well as negative regulation of FynT activity. In resting T-cells, the transmembrane adaptor protein PAG (phosphoprotein associated with glycosphingolipid-enriched microdomains) is constitutively tyrosine-phosphorylated, a state maintained by the Src family kinase FynT. PAG has a role in negative regulation of Src family kinases in T-cells by recruitment of Csk (C-terminal Src kinase) to the membrane via binding to PAG phosphotyrosine 317. The interaction between FynT and PAG is essential for PAG function; however, so far the FynT binding mode has been unknown. Here, we demonstrate that the FynT-PAG complex formation is a dual domain docking process, involving SH2 domain binding to PAG phosphotyrosines as well as an SH3 domain interaction with the first proline-rich region of PAG. This binding mode affects FynT kinase activity, PAG phosphorylation, and recruitment of FynT and Csk, demonstrated in Jurkat TAg cells after antibody stimulation of the T cell receptor. Furthermore, we show that TCR-induced tyrosine phosphorylation is regulated by SH3 domain modulation of the FynT-PAG interaction in human primary T-cells. Although FynT SH3 domain association is shown to be crucial for efficiently initiating PAG phosphorylation, we suggest that engagement of the SH2 domain on PAG renders FynT insensitive to Csk negative regulation. Thus, in T-cells, PAG is involved in positive as well as negative regulation of FynT activity. Protein-tyrosine kinases are key mediators of signaling through cell surface receptors, and specificity and regulation of their activities is critical for creating the correct responses to external stimuli. In T-cells, ligand engagement of the T-cell receptor leads to activation of proximal protein-tyrosine kinases of the Src kinase family (Lck and FynT), which subsequently induce tyrosine phosphorylation of proteins in the T-cell receptor (TCR) 2The abbreviations used are: TCRT-cell receptorGSTglutathione S-transferaseSFKSrc family kinaseSH2Src homology 2SH3Src homology 3WTwild type. complex (1Palacios E.H. Weiss A. Oncogene. 2004; 23: 7990-8000Crossref PubMed Scopus (532) Google Scholar, 2Straus D.B. Weiss A. Cell. 1992; 70: 585-593Abstract Full Text PDF PubMed Scopus (935) Google Scholar). Recruitment and activation of the kinase Zap-70 to the complex initiates an array of downstream events involving other enzymes and cellular adaptor and scaffold proteins and finally results in nuclear transcription, changes in T-cell morphology, and proliferation. T-cell receptor glutathione S-transferase Src family kinase Src homology 2 Src homology 3 wild type. Protein-tyrosine kinases of the Src kinase family have a conserved modular architecture fundamental to their highly specific function, interactions, and regulation (3Boggon T.J. Eck M.J. Oncogene. 2004; 23: 7918-7927Crossref PubMed Scopus (516) Google Scholar). The archetypal Src family kinase (SFK) consists of an N-terminal membrane-targeting region (myristoylated and/or palmitoylated) (4Resh M.D. Biochim. Biophys. Acta. 1999; 1451: 1-16Crossref PubMed Scopus (1079) Google Scholar), followed by successive SH3 and SH2 domains, capable of binding to proline-rich and phosphotyrosine-containing motifs, respectively, as well as a catalytic domain. In addition, SFKs contain a regulatory tyrosine residue within the kinase domain and an autoinhibitory tyrosine phosphorylation site in the C-terminal tail (5Nada S. Okada M. MacAuley A. Cooper J.A. Nakagawa H. Nature. 1991; 351: 69-72Crossref PubMed Scopus (511) Google Scholar, 6Arold S.T. Ulmer T.S. Mulhern T.D. Werner J.M. Ladbury J.E. Campbell I.D. Noble M.E. J. Biol. Chem. 2001; 276: 17199-17205Abstract Full Text Full Text PDF PubMed Scopus (75) Google Scholar, 7Ulmer T.S. Werner J.M. Campbell I.D. Structure. 2002; 10: 901-911Abstract Full Text Full Text PDF PubMed Scopus (37) Google Scholar). Regulation of SFKs is mediated by the cytoplasmic kinase Csk (C-terminal Src kinase), which phosphorylates the C-terminal tyrosine of SFKs to initiate the formation of an inactive, closed configuration through intramolecular engagement of the SH2 domain. Phosphoprotein associated with glycosphingolipid-enriched microdomains (hereafter referred to as PAG) (8Kawabuchi M. Satomi Y. Takao T. Shimonishi Y. Nada S. Nagai K. Tarakhovsky A. Okada M. Nature. 2000; 404: 999-1003Crossref PubMed Scopus (464) Google Scholar, 9Brdicka T. Pavlistova D. Leo A. Bruyns E. Korinek V. Angelisova P. Scherer J. Shevchenko A. Hilgert I. Cerny J. Drbal K. Kuramitsu Y. Kornacker B. Horejsi V. Schraven B. J. Exp. Med. 2000; PubMed Scopus Google Scholar), is a transmembrane adaptor protein involved in the negative regulatory of SFKs by of Csk to through specific binding of the SH2 domain to tyrosine in The interaction Csk S. Y. A. K. Okada M. J. Biol. Chem. 2000; Full Text Full Text PDF PubMed Scopus Google Scholar), which subsequently by the regulatory C-terminal tyrosine of as is to by and consists of a cytoplasmic domain proline-rich as well as tyrosine of which are for phosphorylation by In resting T-cells, PAG is constitutively however, stimulation of the a of to a of Csk T. Pavlistova D. Leo A. Bruyns E. Korinek V. Angelisova P. Scherer J. Shevchenko A. Hilgert I. Cerny J. Drbal K. Kuramitsu Y. Kornacker B. Horejsi V. Schraven B. J. Exp. Med. 2000; PubMed Scopus Google Scholar, T. H. S. Horejsi V. Schraven B. B. T. K. J. Biol. Chem. 2001; 276: Full Text Full Text PDF PubMed Scopus Google Scholar). The the signaling mediators and FynT to initiating a TCR-induced tyrosine phosphorylation to T-cell activation K. T. S. Tarakhovsky A. Nature. PubMed Scopus Google Scholar). of signaling by of PAG tyrosine and recruitment of Csk to role in negative regulation has been for PAG through association with which a between and the T. J. Angelisova P. Horejsi V. 2001; PubMed Scopus Google Scholar, K. M. S. A. H. M. Okada M. T. J. 2002; PubMed Scopus Google Scholar). PAG phosphorylation and Csk recruitment are in cells T. Pavlistova D. Leo A. Bruyns E. Korinek V. Angelisova P. Scherer J. Shevchenko A. Hilgert I. Cerny J. Drbal K. Kuramitsu Y. Kornacker B. Horejsi V. Schraven B. J. Exp. Med. 2000; PubMed Scopus Google Scholar, A. Bruyns E. H. Schraven B. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus Google Scholar, K. M. T. Okada M. T. T. Y. A. S. T. A. J. 2002; PubMed Scopus Google Scholar, T. Nada S. Okada M. S. A. PubMed Scopus Google Scholar), that the FynT-PAG complex formation is essential for the negative regulatory role of PAG. is for the has been that the association is mediated by binding of the FynT SH2 domain to in PAG T. Pavlistova D. Leo A. Bruyns E. Korinek V. Angelisova P. Scherer J. Shevchenko A. Hilgert I. Cerny J. Drbal K. Kuramitsu Y. Kornacker B. Horejsi V. Schraven B. J. Exp. Med. 2000; PubMed Scopus Google Scholar). via the FynT SH3 domain has been of PAG have been shown to FynT association D. Schraven B. A. Biol. PubMed Scopus Google Scholar). phosphorylation of PAG in cells is on the association with the H. Okada M. T. J. 2002; PubMed Scopus Google Scholar, S. M. Y. J. J. Exp. Med. 2004; PubMed Scopus Google Scholar, J. Y. M. Horejsi V. T. J. PubMed Scopus Google Scholar), and interaction has been shown to dual binding of SH3 and SH2 E. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus (37) Google Scholar). In we a of the FynT-PAG interaction a array in with results the complex formation as a dual domain binding process, involving binding of the FynT SH3 domain to the first proline-rich in PAG and a FynT interaction with PAG to we that the FynT kinase is for Csk C-terminal however, of FynT is FynT PAG. Thus, binding to PAG is for positive as well as negative regulation of FynT activity. results are in a by in Jurkat TAg FynT and Csk with PAG and the of stimulation on as well as on PAG In human primary T-cells, modulation of the FynT-PAG interaction is shown to TCR-induced tyrosine Csk, and glutathione S-transferase The antibody by of a cell the proteins and and the kinase The antibody and the and The antibody Zap-70 and FynT a T-cell of the FynT and FynT of binding via SH3 and SH2 domains, H. Biol. 10: PubMed Google Scholar, H. M.D. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus Google Scholar), by The PAG and a C-terminal T. Pavlistova D. Leo A. Bruyns E. Korinek V. Angelisova P. Scherer J. Shevchenko A. Hilgert I. Cerny J. Drbal K. Kuramitsu Y. Kornacker B. Horejsi V. Schraven B. J. Exp. Med. 2000; PubMed Scopus Google Scholar). The PAG tyrosine to in the first proline-rich region as The protein by the of the a residue of the by PAG of the and by to and proteins in the by and as T. H. S. Horejsi V. Schraven B. B. T. K. J. Biol. Chem. 2001; 276: Full Text Full Text PDF PubMed Scopus Google Scholar). and cells maintained in with and and in a of Jurkat TAg cells in with and and by as T. H. S. Horejsi V. Schraven B. B. T. K. J. Biol. Chem. 2001; 276: Full Text Full Text PDF PubMed Scopus Google Scholar), and the in and for T cells by negative as T. H. S. Horejsi V. Schraven B. B. T. K. J. Biol. Chem. 2001; 276: Full Text Full Text PDF PubMed Scopus Google Scholar). the to the in for and and to cells for Jurkat TAg cells with for the primary T cells by followed by the of after 2 for for the as in and by a of and for cell of cells in the and with for 3 subsequently in and to of and on a as A. J. Biol. Google Scholar). with and proteins by the with proteins with and by In as 2000; PubMed Scopus Google with and PAG in the of and for on This followed by a and the by in The by and PAG a of FynT with PAG in have demonstrated that FynT is for PAG phosphorylation and Csk binding by of T-cells K. M. T. Okada M. T. T. Y. A. S. T. A. J. 2002; PubMed Scopus Google Scholar). have been to the of the interaction between FynT and PAG. of the FynT SH2 SH3 has been and of proteins T. Pavlistova D. Leo A. Bruyns E. Korinek V. Angelisova P. Scherer J. Shevchenko A. Hilgert I. Cerny J. Drbal K. Kuramitsu Y. Kornacker B. Horejsi V. Schraven B. J. Exp. Med. 2000; PubMed Scopus Google Scholar, A. Bruyns E. H. Schraven B. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus Google Scholar, D. Schraven B. A. Biol. PubMed Scopus Google Scholar). In to of FynT in the association with we of and to SH2 and SH3 domain is a highly conserved in Src SH3 domains, and of residue is to SH3 domain H. Biol. 10: PubMed Google Scholar). The FynT a of a critical residue in the SH2 which has been shown to phosphotyrosine binding of Src family kinases H. M.D. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus Google Scholar). and of the are shown in and we cells with to of tyrosine phosphorylation, subsequently a SH2 domain interaction with PAG In addition, cells with in to of PAG phosphorylation in cells and after with FynT. that PAG phosphorylation in cells is after of cells have constitutively PAG that of PAG in cells of FynT is by in the cells a interaction between FynT and PAG and binding for FynT and FynT via the SH2 domain the interaction mediated by the SH3 domain The to the binding for domains, and SH2 are to with with phosphotyrosines J.E. M. J. J. S. A. PubMed Scopus Google Scholar), SH3 with to proline-rich T. Cell. 1992; Full Text PDF PubMed Scopus Google Scholar). to PAG a FynT of via domain and that the FynT-PAG interaction involved domain. of the FynT SH3 cytoplasmic tail of PAG proline-rich with the and In phosphorylation of PAG is on the kinase and the proline-rich region has been as a binding site for in a E. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus (37) Google Scholar). the FynT SH3 site on we a by a array on of This which the PAG with with positive as in which the first proline-rich region as in the PAG the membrane with protein interaction The FynT SH3 interaction subsequently by and C-terminal to the of the interaction site and as the and C-terminal for Furthermore, by of and as essential for interaction between PAG and the FynT SH3 domain Thus, the of the binding site which is to the for SH3 S. S. A. PubMed Scopus Google Scholar). The critical residue the of the FynT SH3 domain binding to PAG by a with a conserved residue within the SH3 domain S. S. Biol. PubMed Scopus Google Scholar). of the FynT SH3 domain interaction a by the the interaction site by array the and of the as essential for interaction with the FynT SH3 domain. we and which in binding with and C-terminal to the binding have been shown to SH3 domain binding and as of SH3 and however, have been shown to an S. S. A. PubMed Scopus Google Scholar, M.J. S. A. PubMed Scopus Google Scholar). the interaction by the we capable of creating an binding for SH3 of binding the and their for the FynT SH3 domain The binding the binding with and by in and PAG to a ligand for FynT. This referred to as used in as a for the of kinase and of FynT SH3 in of PAG and the critical by the to of SH3 domain binding the FynT which association with we capable of binding via the SH3 domain with a PAG a and This a in is that the binding is a of of SH2 domain through of that the are capable of the interaction with PAG. of interaction with the which a in FynT SH3 domain binding of of the FynT SH2 array of PAG phosphotyrosine tyrosine to interaction with FynT proteins interaction with the first proline-rich region of PAG in addition, we that the proteins capable of with a tyrosine has been that the SH2 domain to phosphotyrosine-containing S. M. 1999; PubMed Scopus Google to the of phosphotyrosine-containing on array the of the PAG phosphotyrosine involved in FynT SH2 domain we PAG tyrosine to the phosphotyrosine PAG tyrosine by cells with FynT and the PAG to the SH2 domain interaction in In addition, we FynT and cells with to tyrosine phosphorylation and SH2 domain that residue which with FynT in the a for tyrosine kinases in cells as by antibody of tyrosine The of FynT and FynT binding to PAG to be a of with the FynT SH3 domain. the N-terminal tyrosine and as interaction for the FynT SH2 domain in of however, the SH3 domain interaction is by residue of the binding we interaction with and results by cells with FynT and PAG of site in a in with that tyrosine are to SH2 domain binding T. Pavlistova D. Leo A. Bruyns E. Korinek V. Angelisova P. Scherer J. Shevchenko A. Hilgert I. Cerny J. Drbal K. Kuramitsu Y. Kornacker B. Horejsi V. Schraven B. J. Exp. Med. 2000; PubMed Scopus Google Scholar). of a PAG in a of FynT SH2 domain on we that FynT is capable of binding phosphotyrosine and and that of of be for through binding of the other FynT and PAG as well as PAG in the SH3 and/or SH2 we cells with FynT and PAG as of the SH2 domain interaction by of PAG and the FynT binding and followed by a in phosphorylation and Csk the to FynT binding an interaction by a in tyrosine phosphorylation and Csk binding a of the interaction with of tyrosine phosphorylation and recruitment of PAG and of FynT of PAG on PAG phosphorylation by in phosphorylation In a FynT and with a of a of and phosphorylation followed by the of with PAG demonstrated a phosphorylation and of PAG after a of 2 to PAG with an of phosphotyrosine The the however, the of the The of FynT SH3 domain binding modulation through phosphorylation with PAG a with for the FynT SH3 domain Here, phosphorylation and PAG a phosphorylation In a process, between kinase and the SH2 domain binding are the to via SH2 domain PAG is however, is that of In the SH3 a of demonstrated the of an SH3 domain binding site for engagement of the SH3 and the interaction critical for FynT kinase for of the kinase and phosphorylation of of the SH2 domain binding by of the and as binding for the FynT SH2 domain in a PAG as a an of tyrosine for of the SH2 domain interaction PAG in of the the the of of phosphorylation The of PAG as a the Thus, and downstream of the SH3 domain interaction to be and phosphorylation as shown is of a phosphorylation and of is 2000; PubMed Scopus Google Scholar), and to we phosphorylation with phosphorylation is phosphorylation are by the associated with is for In phosphorylation in a is a involving between and a the in a phosphorylation in of PubMed Scopus Google Scholar, P. J. Biol. Chem. 2001; 276: Full Text Full Text PDF PubMed Scopus Google Scholar). and 3 and PAG and we phosphorylation after and 2 The PAG and PAG with SH3 domain interaction changes in for of the and with of In of PAG phosphorylation and The in of and the of are of a phosphorylation In we have shown that PAG is by FynT and that binding of the FynT SH3 domain to the first proline-rich region of PAG is essential for and for tyrosine phosphorylation of PAG. with results by a for the interaction and in phosphorylation through of the PAG in Jurkat TAg In FynT capable of PAG as well as a PAG the SH2 through by of the phosphorylation as well as the association with FynT and This that FynT SH2 domain binding is for phosphorylation of by the in phosphorylation of PAG SH3 domain interaction and the SH3 PAG phosphorylation in Jurkat TAg the of FynT by FynT to results with and recruitment of Csk and FynT to the PAG in to the of PAG a after stimulation by and PAG phosphorylation by FynT as well as recruitment of Csk and FynT to PAG in Jurkat TAg cells a of PAG phosphorylation to the with in between PAG and the the phosphorylation of of and in PAG phosphorylation, and a in phosphotyrosines for the results that in with in the in phosphorylation of FynT and Csk the PAG complex in to antibody stimulation and PAG The for with in association after of the complex for PAG and the in phosphotyrosine In the FynT association for the the results demonstrate that the FynT-PAG complex formation is mediated by a dual domain binding and that modulation of the binding affects FynT recruitment and as well as PAG phosphorylation and Csk recruitment in Jurkat TAg cells after The and shown to the on PAG tyrosine phosphorylation, to the of PAG on TCR-induced primary T-cells with FynT and as well as with PAG and with followed by and protein tyrosine phosphorylation in cell with of FynT protein tyrosine phosphorylation as by and Zap-70 used to the of PAG phosphorylation as shown in The of tyrosine phosphorylation the of SH3 PAG phosphorylation in the stimulation in of PAG in with by D. M. Horejsi V. A. Biol. 23: PubMed Scopus Google Scholar). of PAG tyrosine phosphorylation however, with PAG in phosphorylation of Zap-70 as well as In tyrosine phosphorylation of by the of the the of PAG as a negative of signaling mediated via PAG phosphorylation and Csk the regulation and of a in proximal T-cell and of kinases and adaptor proteins that as for FynT is critical to of the role of kinase in T-cell activation and FynT is associated with PAG in resting however, so key the complex formation have been and T. Pavlistova D. Leo A. Bruyns E. Korinek V. Angelisova P. Scherer J. Shevchenko A. Hilgert I. Cerny J. Drbal K. Kuramitsu Y. Kornacker B. Horejsi V. Schraven B. J. Exp. Med. 2000; PubMed Scopus Google Scholar, A. Bruyns E. H. Schraven B. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus Google Scholar, D. Schraven B. A. Biol. PubMed Scopus Google Scholar, D. Biol. 2001; PubMed Scopus Google Scholar). for a binding involving interaction domain. In we show that complex formation between FynT and PAG is mediated by a dual domain docking involving SH3 and SH2 of which to binding specificity and kinase activity. SH3 the first proline-rich region of PAG as a ligand for the domain by array This region of PAG with binding the of the of SH3 S. S. A. PubMed Scopus Google Scholar, J.A. M.J. J. PubMed Scopus Google Scholar). by of critical in however, to the SH3 domain interaction The binding be by of SH2 domain in the FynT by between FynT and PAG the binding a of SH3 domain binding in other S. S. A. PubMed Scopus Google Scholar). the complex be by with Csk to PAG by with other proteins to be This is PAG has a of interaction and the formation of involving PAG has been M. A. Horejsi V. Schraven B. J.A. PubMed Scopus Google Scholar). binding of the SH3 domain to ligand FynT kinase in in phosphorylation Thus, be to complex formation via the SH3 an is to induce the changes to FynT and phosphorylation of PAG. results are in with a for SH3 regulation of of Src family kinases via of intramolecular and of the 2000; PubMed Scopus Google Scholar, I. M. M. J. Nature. PubMed Scopus Google Scholar). In regulation of FynT kinase via SH3 domain demonstrated by the of a SH3 domain which PAG phosphorylation The ligand have as a to with cell of FynT SH2 that PAG has FynT SH2 phosphotyrosines in and the and a residue the for SH2 domain interaction (3Boggon T.J. Eck M.J. Oncogene. 2004; 23: 7918-7927Crossref PubMed Scopus (516) Google Scholar, D. J. Cell. Full Text PDF PubMed Scopus Google Scholar). to between the with and of SH2 domain binding a PAG we that and are for the FynT SH2 domain. 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PubMed Scopus Google Scholar), and is that in is the of the in PAG the results the of a in other cell PAG as a docking for and regulation of kinases binding to the adaptor be through to of of the FynT binding on PAG phosphorylation and recruitment of Csk and FynT in a and in Jurkat TAg results the of the PAG site by of PAG phosphorylation as well as FynT and Csk In the SH3 domain interaction via phosphorylation and FynT of the SH2 phosphotyrosines and to PAG phosphorylation as well as FynT and Csk The results in phosphorylation and to in kinase recruitment that an SH2 domain interaction is essential for phosphorylation of as well as the FynT This is in with results by T. Pavlistova D. Leo A. Bruyns E. Korinek V. Angelisova P. Scherer J. Shevchenko A. Hilgert I. Cerny J. Drbal K. Kuramitsu Y. Kornacker B. Horejsi V. Schraven B. J. Exp. Med. 2000; PubMed Scopus Google Scholar, A. Bruyns E. H. Schraven B. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus Google Scholar, D. Schraven B. A. Biol. PubMed Scopus Google Scholar), that of other stimulation of the Jurkat TAg cells a and of Csk and and results a of the complex to that of FynT and PAG with a for the This by D. Schraven B. A. Biol. PubMed Scopus Google however, a be The for of PAG is and that be regulated in as D. M. Horejsi V. A. Biol. 23: PubMed Scopus Google Scholar). have on a role for PAG in in T-cells D. Schraven B. A. Biol. PubMed Scopus Google Scholar, M. A. Horejsi V. Schraven B. J.A. PubMed Scopus Google Scholar). T-cells have FynT as well as of Thus, is to that the have as an for by as in The of PAG is mediated through tyrosine phosphorylation, and to the regulatory of PAG on TCR-induced tyrosine phosphorylation, we used PAG and which PAG with and phosphorylation of the PAG in human primary T-cells on tyrosine phosphorylation of and with a negative in through protein tyrosine in show that engagement of SH3 and SH2 affects PAG phosphorylation the regulation of FynT activity. Recruitment of Csk to PAG has been shown to C-terminal phosphorylation of FynT as by M. A. Horejsi V. Schraven B. J.A. PubMed Scopus Google Scholar). we the binding for formation of the complex in resting T-cells the FynT SH3 domain a first with which the of FynT and PAG tyrosine has been for T. K. Y. H. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus Google and for the complex formation between Src family kinases and D. Nature. PubMed Scopus Google Scholar, S. D. D. Biol. PubMed Google Scholar), a role for the SH3 domain in to tyrosine This interaction be and in kinase tyrosine phosphorylation of and recruitment of other SH2 as a of Csk is in to which for phosphorylation of the C-terminal tyrosine residue of the domain on however, that FynT and that the is FynT PAG and an be role for the SH2 domain in for by Csk has been for T. Angelisova P. J. Hilgert I. J. S. Schraven B. Horejsi V. J. Exp. Med. PubMed Scopus Google and for FynT M. A. Horejsi V. Schraven B. J.A. PubMed Scopus Google Scholar). In results show that FynT binding to PAG is a involving SH3 and SH2 The of binding in PAG is to specificity and of interaction by an with engagement of the FynT SH2 domain after tyrosine phosphorylation of PAG. The dual domain binding the FynT-PAG complex the and in cell and for