The Experts below are selected from a list of 15 Experts worldwide ranked by ideXlab platform
Joseph Schlessinger - One of the best experts on this subject based on the ideXlab platform.
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the sh2 and sh3 domain containing Nck Protein is oncogenic and a common target for phosphorylation by different surface receptors
Molecular and Cellular Biology, 1992Co-Authors: Edward Y Skolnik, A Ullrich, Joseph SchlessingerAbstract:Signalling Proteins such as phospholipase C-gamma (PLC-gamma) or GTPase-activating Protein (GAP) of ras contain conserved regions of approximately 100 amino acids termed src homology 2 (SH2) domains. SH2 domains were shown to be responsible for mediating association between signalling Proteins and tyrosine-phosphorylated Proteins, including growth factor receptors. Nck is an ubiquitously expressed Protein consisting exclusively of one SH2 and three SH3 domains. Here we show that epidermal growth factor or platelet-derived growth factor stimulation of intact human or murine cells leads to phosphorylation of Nck Protein on tyrosine, serine, and threonine residues. Similar stimulation of Nck phosphorylation was detected upon activation of rat basophilic leukemia RBL-2H3 cells by cross-linking of the high-affinity immunoglobulin E receptors (Fc epsilon RI). Ligand-activated, tyrosine-autophosphorylated platelet-derived growth factor or epidermal growth factor receptors were coimmunoprecipitated with anti-Nck antibodies, and the association with either receptor molecule was mediated by the SH2 domain of Nck. Addition of phorbol ester was also able to stimulate Nck phosphorylation on serine residues. However, growth factor-induced serine/threonine phosphorylation of Nck was not mediated by Protein kinase C. Interestingly, approximately fivefold overexpression of Nck in NIH 3T3 cells resulted in formation of oncogenic foci. These results show that Nck is an oncogenic Protein and a common target for the action of different surface receptors. Nck probably functions as an adaptor Protein which links surface receptors with tyrosine kinase activity to downstream signalling pathways involved in the control of cell proliferation.
Hidesaburo Hanafusa - One of the best experts on this subject based on the ideXlab platform.
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the sh2 and sh3 containing Nck Protein transforms mammalian fibroblasts in the absence of elevated phosphotyrosine levels
Molecular and Cellular Biology, 1992Co-Authors: Margaret M Chou, J E Fajardo, Hidesaburo HanafusaAbstract:We have established the human Nck sequence as a new oncogene. Nck encodes one SH2 and three SH3 domains, the Src homology motifs found in nonreceptor tyrosine kinases, Ras GTPase-activating Protein, phosphatidylinositol 3-kinase, and phospholipase C-gamma. Overexpression of human Nck in 3Y1 rat fibroblasts results in transformation as judged by alteration of cell morphology, colony formation in soft agar, and tumor formation in nude BALB/c mice. However, overexpression of Nck does not induce detectable elevation of the phosphotyrosine content of specific Proteins, as is observed for v-crk, another SH2/SH3-containing oncogene. Despite this fact, we demonstrate that Nck retains the ability to bind tyrosine phosphorylated Proteins in vitro, using a fusion Protein of Nck with glutathione-S-transferase (GST). Moreover, when incubated with lysates prepared from v-src-transformed 3Y1 cells or the Nck-overexpressing cell lines, GST-Nck binds to both p60v-src and serine/threonine kinases, respectively. Although phosphotyrosine levels are not elevated in the Nck-expressing fibroblasts, vanadate treatment of these cells results in a phosphotyrosine pattern that is altered from the parental 3Y1 pattern, suggestive of a perturbation of indigenous tyrosine kinase pathways. These results suggest the possibility that human Nck induces transformation in 3Y1 fibroblasts by virtue of its altered affinity or specificity for the normal substrates of its rat homolog and that Nck may play a role in linking tyrosine and serine/threonine kinase pathways within the cell.
Daeho Park - One of the best experts on this subject based on the ideXlab platform.
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cloning sequencing and overexpression of sh2 sh3 adaptor Protein Nck from mouse thymus
Molecules and Cells, 1997Co-Authors: Daeho ParkAbstract:Nck, an oncogenic Protein containing one SH2 and three SH3 domains, is a common target for phosphorylation by a variety of cell surface receptors. The absence of a recognizable catalytic domain of Nck suggests that Nck serves as a linker molecule to couple cell surface receptors to downstream effector molecules that regulate cellular responses induced by receptor activation. In this study, we isolated Nck cDNA from mouse thymus by screening a phase expression library using monoclonal antibody (mAb) B16-5 which recognizes the SH3 domain of phospholipase C-gamma 1. Nck Protein was purified from an extract of the Sf9 cell that had been infected with recombinant baculovirus containing mouse Nck cDNA. The purified Protein exhibited an apparent molecular mass of 47 kDa on SDS-polyacrylamide gels. Nck antibody was generated in rabbits using purified Protein as an antigen. The distribution of Nck Protein in rat tissues examined by immunoblots showed that Nck is expressed widely, and that brain, spleen, and tests contain more Nck than other tissues examined.
Edward Y Skolnik - One of the best experts on this subject based on the ideXlab platform.
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the sh2 and sh3 domain containing Nck Protein is oncogenic and a common target for phosphorylation by different surface receptors
Molecular and Cellular Biology, 1992Co-Authors: Edward Y Skolnik, A Ullrich, Joseph SchlessingerAbstract:Signalling Proteins such as phospholipase C-gamma (PLC-gamma) or GTPase-activating Protein (GAP) of ras contain conserved regions of approximately 100 amino acids termed src homology 2 (SH2) domains. SH2 domains were shown to be responsible for mediating association between signalling Proteins and tyrosine-phosphorylated Proteins, including growth factor receptors. Nck is an ubiquitously expressed Protein consisting exclusively of one SH2 and three SH3 domains. Here we show that epidermal growth factor or platelet-derived growth factor stimulation of intact human or murine cells leads to phosphorylation of Nck Protein on tyrosine, serine, and threonine residues. Similar stimulation of Nck phosphorylation was detected upon activation of rat basophilic leukemia RBL-2H3 cells by cross-linking of the high-affinity immunoglobulin E receptors (Fc epsilon RI). Ligand-activated, tyrosine-autophosphorylated platelet-derived growth factor or epidermal growth factor receptors were coimmunoprecipitated with anti-Nck antibodies, and the association with either receptor molecule was mediated by the SH2 domain of Nck. Addition of phorbol ester was also able to stimulate Nck phosphorylation on serine residues. However, growth factor-induced serine/threonine phosphorylation of Nck was not mediated by Protein kinase C. Interestingly, approximately fivefold overexpression of Nck in NIH 3T3 cells resulted in formation of oncogenic foci. These results show that Nck is an oncogenic Protein and a common target for the action of different surface receptors. Nck probably functions as an adaptor Protein which links surface receptors with tyrosine kinase activity to downstream signalling pathways involved in the control of cell proliferation.
Margaret M Chou - One of the best experts on this subject based on the ideXlab platform.
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the sh2 and sh3 containing Nck Protein transforms mammalian fibroblasts in the absence of elevated phosphotyrosine levels
Molecular and Cellular Biology, 1992Co-Authors: Margaret M Chou, J E Fajardo, Hidesaburo HanafusaAbstract:We have established the human Nck sequence as a new oncogene. Nck encodes one SH2 and three SH3 domains, the Src homology motifs found in nonreceptor tyrosine kinases, Ras GTPase-activating Protein, phosphatidylinositol 3-kinase, and phospholipase C-gamma. Overexpression of human Nck in 3Y1 rat fibroblasts results in transformation as judged by alteration of cell morphology, colony formation in soft agar, and tumor formation in nude BALB/c mice. However, overexpression of Nck does not induce detectable elevation of the phosphotyrosine content of specific Proteins, as is observed for v-crk, another SH2/SH3-containing oncogene. Despite this fact, we demonstrate that Nck retains the ability to bind tyrosine phosphorylated Proteins in vitro, using a fusion Protein of Nck with glutathione-S-transferase (GST). Moreover, when incubated with lysates prepared from v-src-transformed 3Y1 cells or the Nck-overexpressing cell lines, GST-Nck binds to both p60v-src and serine/threonine kinases, respectively. Although phosphotyrosine levels are not elevated in the Nck-expressing fibroblasts, vanadate treatment of these cells results in a phosphotyrosine pattern that is altered from the parental 3Y1 pattern, suggestive of a perturbation of indigenous tyrosine kinase pathways. These results suggest the possibility that human Nck induces transformation in 3Y1 fibroblasts by virtue of its altered affinity or specificity for the normal substrates of its rat homolog and that Nck may play a role in linking tyrosine and serine/threonine kinase pathways within the cell.
