Journal articles: 'Protein-tyrosine kinases'

1

Lawrence, David S., and Jinkui Niu. "Protein Kinase InhibitorsThe Tyrosine-Specific Protein Kinases." Pharmacology & Therapeutics 77, no. 2 (February 1998): 81–114. http://dx.doi.org/10.1016/s0163-7258(97)00052-1.

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2

Hunter, T., and J. A. Cooper. "Protein-Tyrosine Kinases." Annual Review of Biochemistry 54, no. 1 (June 1985): 897–930. http://dx.doi.org/10.1146/annurev.bi.54.070185.004341.

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3

Mahajan, S., J. Fargnoli, A. L. Burkhardt, S. A. Kut, S. J. Saouaf, and J. B. Bolen. "Src family protein tyrosine kinases induce autoactivation of Bruton's tyrosine kinase." Molecular and Cellular Biology 15, no. 10 (October 1995): 5304–11. http://dx.doi.org/10.1128/mcb.15.10.5304.

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Bruton's tyrosine kinase (Btk) is tyrosine phosphorylated and enzymatically activated following ligation of the B-cell antigen receptor. These events are temporally regulated, and Btk activation follows that of various members of the Src family of protein tyrosine kinases, thus raising the possibility that Src kinases participate in the Btk activation process. We have evaluated the mechanism underlying Btk enzyme activation and have explored the potential regulatory relationship between Btk and Src protein kinases. We demonstrate in COS transient-expression assays that Btk can be activated through intramolecular autophosphorylation at tyrosine 551 and that Btk autophosphorylation is required for Btk catalytic functions. Coexpression of Btk with members of the Src family of protein tyrosine kinases, but not Syk, led to Btk tyrosine phosphorylation and activation. Using a series of point mutations in Blk (a representative Src protein kinase) and Btk, we show that Src kinases activate Btk through an indirect mechanism that requires membrane association of the Src enzymes as well as functional Btk SH3 and SH2 domains. Our results are compatible with the idea that Src protein tyrosine kinases contribute to Btk activation by indirectly stimulating Btk intramolecular autophosphorylation.

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4

Dailey, D., G. L. Schieven, M. Y. Lim, H. Marquardt, T. Gilmore, J. Thorner, and G. S. Martin. "Novel yeast protein kinase (YPK1 gene product) is a 40-kilodalton phosphotyrosyl protein associated with protein-tyrosine kinase activity." Molecular and Cellular Biology 10, no. 12 (December 1990): 6244–56. http://dx.doi.org/10.1128/mcb.10.12.6244-6256.1990.

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Extracts of bakers' yeast (Saccharomyces cerevisiae) contain protein-tyrosine kinase activity that can be detected with a synthetic Glu-Tyr copolymer as substrate (G. Schieven, J. Thorner, and G.S. Martin, Science 231:390-393, 1986). By using this assay in conjunction with ion-exchange and affinity chromatography, a soluble tyrosine kinase activity was purified over 8,000-fold from yeast extracts. The purified activity did not utilize typical substrates for mammalian protein-tyrosine kinases (enolase, casein, and histones). The level of tyrosine kinase activity at all steps of each preparation correlated with the content of a 40-kDa protein (p40). Upon incubation of the most highly purified fractions with Mn-ATP or Mg-ATP, p40 was the only protein phosphorylated on tyrosine. Immunoblotting of purified p40 or total yeast extracts with antiphosphotyrosine antibodies and phosphoamino acid analysis of 32P-labeled yeast proteins fractionated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis indicated that the 40-kDa protein is normally phosphorylated at tyrosine in vivo. 32P-labeled p40 immunoprecipitated from extracts of metabolically labeled cells by affinity-purified anti-p40 antibodies contained both phosphoserine and phosphotyrosine. The gene encoding p40 (YPK1) was cloned from a yeast genomic library by using oligonucleotide probes designed on the basis of the sequence of purified peptides. As deduced from the nucleotide sequence of YPK1, p40 is homologous to known protein kinases, with features that resemble known protein-serine kinases more than known protein-tyrosine kinases. Thus, p40 is a protein kinase which is phosphorylated in vivo and in vitro at both tyrosine and serine residues; it may be a novel type of autophosphorylating tyrosine kinase, a bifunctional (serine/tyrosine-specific) protein kinase, or a serine kinase that is a substrate for an associated tyrosine kinase.

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5

Dailey, D., G. L. Schieven, M. Y. Lim, H. Marquardt, T. Gilmore, J. Thorner, and G. S. Martin. "Novel yeast protein kinase (YPK1 gene product) is a 40-kilodalton phosphotyrosyl protein associated with protein-tyrosine kinase activity." Molecular and Cellular Biology 10, no. 12 (December 1990): 6244–56. http://dx.doi.org/10.1128/mcb.10.12.6244.

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Extracts of bakers' yeast (Saccharomyces cerevisiae) contain protein-tyrosine kinase activity that can be detected with a synthetic Glu-Tyr copolymer as substrate (G. Schieven, J. Thorner, and G.S. Martin, Science 231:390-393, 1986). By using this assay in conjunction with ion-exchange and affinity chromatography, a soluble tyrosine kinase activity was purified over 8,000-fold from yeast extracts. The purified activity did not utilize typical substrates for mammalian protein-tyrosine kinases (enolase, casein, and histones). The level of tyrosine kinase activity at all steps of each preparation correlated with the content of a 40-kDa protein (p40). Upon incubation of the most highly purified fractions with Mn-ATP or Mg-ATP, p40 was the only protein phosphorylated on tyrosine. Immunoblotting of purified p40 or total yeast extracts with antiphosphotyrosine antibodies and phosphoamino acid analysis of 32P-labeled yeast proteins fractionated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis indicated that the 40-kDa protein is normally phosphorylated at tyrosine in vivo. 32P-labeled p40 immunoprecipitated from extracts of metabolically labeled cells by affinity-purified anti-p40 antibodies contained both phosphoserine and phosphotyrosine. The gene encoding p40 (YPK1) was cloned from a yeast genomic library by using oligonucleotide probes designed on the basis of the sequence of purified peptides. As deduced from the nucleotide sequence of YPK1, p40 is homologous to known protein kinases, with features that resemble known protein-serine kinases more than known protein-tyrosine kinases. Thus, p40 is a protein kinase which is phosphorylated in vivo and in vitro at both tyrosine and serine residues; it may be a novel type of autophosphorylating tyrosine kinase, a bifunctional (serine/tyrosine-specific) protein kinase, or a serine kinase that is a substrate for an associated tyrosine kinase.

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6

Creeden, Justin F., Khaled Alganem, Ali S. Imami, F. Charles Brunicardi, Shi-He Liu, Rammohan Shukla, Tushar Tomar, Faris Naji, and Robert E. McCullumsmith. "Kinome Array Profiling of Patient-Derived Pancreatic Ductal Adenocarcinoma Identifies Differentially Active Protein Tyrosine Kinases." International Journal of Molecular Sciences 21, no. 22 (November 17, 2020): 8679. http://dx.doi.org/10.3390/ijms21228679.

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Pancreatic cancer remains one of the most difficult malignancies to treat. Minimal improvements in patient outcomes and persistently abysmal patient survival rates underscore the great need for new treatment strategies. Currently, there is intense interest in therapeutic strategies that target tyrosine protein kinases. Here, we employed kinome arrays and bioinformatic pipelines capable of identifying differentially active protein tyrosine kinases in different patient-derived pancreatic ductal adenocarcinoma (PDAC) cell lines and wild-type pancreatic tissue to investigate the unique kinomic networks of PDAC samples and posit novel target kinases for pancreatic cancer therapy. Consistent with previously described reports, the resultant peptide-based kinome array profiles identified increased protein tyrosine kinase activity in pancreatic cancer for the following kinases: epidermal growth factor receptor (EGFR), fms related receptor tyrosine kinase 4/vascular endothelial growth factor receptor 3 (FLT4/VEGFR-3), insulin receptor (INSR), ephrin receptor A2 (EPHA2), platelet derived growth factor receptor alpha (PDGFRA), SRC proto-oncogene kinase (SRC), and tyrosine kinase non receptor 2 (TNK2). Furthermore, this study identified increased activity for protein tyrosine kinases with limited prior evidence of differential activity in pancreatic cancer. These protein tyrosine kinases include B lymphoid kinase (BLK), Fyn-related kinase (FRK), Lck/Yes-related novel kinase (LYN), FYN proto-oncogene kinase (FYN), lymphocyte cell-specific kinase (LCK), tec protein kinase (TEC), hemopoietic cell kinase (HCK), ABL proto-oncogene 2 kinase (ABL2), discoidin domain receptor 1 kinase (DDR1), and ephrin receptor A8 kinase (EPHA8). Together, these results support the utility of peptide array kinomic analyses in the generation of potential candidate kinases for future pancreatic cancer therapeutic development.

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7

Stern, D. F., P. Zheng, D. R. Beidler, and C. Zerillo. "Spk1, a new kinase from Saccharomyces cerevisiae, phosphorylates proteins on serine, threonine, and tyrosine." Molecular and Cellular Biology 11, no. 2 (February 1991): 987–1001. http://dx.doi.org/10.1128/mcb.11.2.987-1001.1991.

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A Saccharomyces cerevisiae lambda gt11 library was screened with antiphosphotyrosine antibodies in an attempt to identify a gene encoding a tyrosine kinase. A subclone derived from one positive phage was sequenced and found to contain an 821-amino-acid open reading frame that encodes a protein with homology to protein kinases. We tested the activity of the putative kinase by constructing a vector encoding a glutathione-S-transferase fusion protein containing most of the predicted polypeptide. The fusion protein phosphorylated endogenous substrates and enolase primarily on serine and threonine. The gene was designated SPK1 for serine-protein kinase. Expression of the Spk1 fusion protein in bacteria stimulated serine, threonine, and tyrosine phosphorylation of bacterial proteins. These results, combined with the antiphosphotyrosine immunoreactivity induced by the kinase, indicate that Spk1 is capable of phosphorylating tyrosine as well as phosphorylating serine and threonine. In in vitro assays, the fusion protein kinase phosphorylated the synthetic substrate poly(Glu/Tyr) on tyrosine, but the activity was weak compared with serine and threonine phosphorylation of other substrates. To determine if other serine/threonine kinases would phosphorylate poly(Glu/Tyr), we tested calcium/calmodulin-dependent protein kinase II and the catalytic subunit of cyclic AMP-dependent protein kinase. The two kinases had similar tyrosine-phosphorylating activities. These results establish that the functional difference between serine/threonine- and tyrosine-protein kinases is not absolute and suggest that there may be physiological circumstances in which tyrosine phosphorylation is mediated by serine/threonine kinases.

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8

Stern, D. F., P. Zheng, D. R. Beidler, and C. Zerillo. "Spk1, a new kinase from Saccharomyces cerevisiae, phosphorylates proteins on serine, threonine, and tyrosine." Molecular and Cellular Biology 11, no. 2 (February 1991): 987–1001. http://dx.doi.org/10.1128/mcb.11.2.987.

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A Saccharomyces cerevisiae lambda gt11 library was screened with antiphosphotyrosine antibodies in an attempt to identify a gene encoding a tyrosine kinase. A subclone derived from one positive phage was sequenced and found to contain an 821-amino-acid open reading frame that encodes a protein with homology to protein kinases. We tested the activity of the putative kinase by constructing a vector encoding a glutathione-S-transferase fusion protein containing most of the predicted polypeptide. The fusion protein phosphorylated endogenous substrates and enolase primarily on serine and threonine. The gene was designated SPK1 for serine-protein kinase. Expression of the Spk1 fusion protein in bacteria stimulated serine, threonine, and tyrosine phosphorylation of bacterial proteins. These results, combined with the antiphosphotyrosine immunoreactivity induced by the kinase, indicate that Spk1 is capable of phosphorylating tyrosine as well as phosphorylating serine and threonine. In in vitro assays, the fusion protein kinase phosphorylated the synthetic substrate poly(Glu/Tyr) on tyrosine, but the activity was weak compared with serine and threonine phosphorylation of other substrates. To determine if other serine/threonine kinases would phosphorylate poly(Glu/Tyr), we tested calcium/calmodulin-dependent protein kinase II and the catalytic subunit of cyclic AMP-dependent protein kinase. The two kinases had similar tyrosine-phosphorylating activities. These results establish that the functional difference between serine/threonine- and tyrosine-protein kinases is not absolute and suggest that there may be physiological circumstances in which tyrosine phosphorylation is mediated by serine/threonine kinases.

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9

Hoekstra, M. F., N. Dhillon, G. Carmel, A. J. DeMaggio, R. A. Lindberg, T. Hunter, and J. Kuret. "Budding and fission yeast casein kinase I isoforms have dual-specificity protein kinase activity." Molecular Biology of the Cell 5, no. 8 (August 1994): 877–86. http://dx.doi.org/10.1091/mbc.5.8.877.

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We have examined the activity and substrate specificity of the Saccharomyces cerevisiae Hrr25p and the Schizosaccharomyces pombe Hhp1, Hhp2, and Cki1 protein kinase isoforms. These four gene products are isotypes of casein kinase I (CKI), and the sequence of these protein kinases predicts that they are protein serine/threonine kinases. However, each of these four protein kinases, when expressed in Escherichia coli in an active form, was recognized by anti-phosphotyrosine antibodies. Phosphoamino acid analysis of 32P-labeled proteins showed phosphorylation on serine, threonine, and tyrosine residues. The E. coli produced forms of Hhp1, Hhp2, and Cki1 were autophosphorylated on tyrosine, and both Hhp1 and Hhp2 were capable of phosphorylating the tyrosine-protein kinase synthetic peptide substrate polymer poly-E4Y1. Immune complex protein kinases assays from S. pombe cells showed that Hhp1-containing precipitates were associated with a protein-tyrosine kinase activity, and the Hhp1 present in these immunoprecipitates was phosphorylated on tyrosine residues. Although dephosphorylation of Hhp1 and Hhp2 by Ser/Thr phosphatase had little effect on the specific activity, tyrosine dephosphorylation of Hhp1 and Hhp2 caused a 1.8-to 3.1-fold increase in the Km for poly-E4Y1 and casein. These data demonstrate that four different CKI isoforms from two different yeasts are capable of protein-tyrosine kinase activity and encode dual-specificity protein kinases.

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10

Shi, Lei, Ahasanul Kobir, Carsten Jers, and Ivan Mijakovic. "Bacterial Protein-Tyrosine Kinases." Current Proteomics 7, no. 3 (October 1, 2010): 188–94. http://dx.doi.org/10.2174/157016410792928198.

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11

Wang, Jean Y. J. "Nuclear protein tyrosine kinases." Trends in Biochemical Sciences 19, no. 9 (September 1994): 373–76. http://dx.doi.org/10.1016/0968-0004(94)90114-7.

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12

Chao, Joseph D., Dennis Wong, and Yossef Av-Gay. "Microbial Protein-tyrosine Kinases." Journal of Biological Chemistry 289, no. 14 (February 19, 2014): 9463–72. http://dx.doi.org/10.1074/jbc.r113.520015.

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13

Gambacorti-Passerini, C. "Oncogenic protein tyrosine kinases." Cellular and Molecular Life Sciences 61, no. 23 (December 2004): 2895–96. http://dx.doi.org/10.1007/s00018-004-4270-1.

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14

Saglio, G., and D. Cilloni. "Oncogenic protein tyrosine kinases." Cellular and Molecular Life Sciences 61, no. 23 (December 2004): 2897–911. http://dx.doi.org/10.1007/s00018-004-4271-0.

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15

Jones, A. V., and N. C. P. Cross. "Oncogenic protein tyrosine kinases." Cellular and Molecular Life Sciences 61, no. 23 (December 2004): 2912–23. http://dx.doi.org/10.1007/s00018-004-4272-z.

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16

Kitamura, Y., and S. Hirotab. "Oncogenic protein tyrosine kinases." Cellular and Molecular Life Sciences 61, no. 23 (December 2004): 2924–31. http://dx.doi.org/10.1007/s00018-004-4273-y.

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17

Naoe, T., and H. Kiyoi. "Oncogenic protein tyrosine kinases." Cellular and Molecular Life Sciences 61, no. 23 (December 2004): 2932–38. http://dx.doi.org/10.1007/s00018-004-4274-x.

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18

Pulford, K., L. Lamant, E. Espinos, Q. Jiang, L. Xue, F. Turturro, G. Delsol, and S. W. Morris. "Oncogenic protein tyrosine kinases." Cellular and Molecular Life Sciences 61, no. 23 (December 2004): 2939–53. http://dx.doi.org/10.1007/s00018-004-4275-9.

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19

Santoro, M., F. Carlomagno, R. M. Melillo, and A. Fusco. "Oncogenic protein tyrosine kinases." Cellular and Molecular Life Sciences 61, no. 23 (December 2004): 2954–64. http://dx.doi.org/10.1007/s00018-004-4276-8.

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20

M�nard, S., P. Casalini, M. Campiglio, S. M. Pupa, and E. Tagliabue. "Oncogenic protein tyrosine kinases." Cellular and Molecular Life Sciences 61, no. 23 (December 2004): 2965–78. http://dx.doi.org/10.1007/s00018-004-4277-7.

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21

Amatya, Neha, David Yin-wei Lin, and Amy H. Andreotti. "Dynamic regulatory features of the protein tyrosine kinases." Biochemical Society Transactions 47, no. 4 (August 8, 2019): 1101–16. http://dx.doi.org/10.1042/bst20180590.

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Abstract The SRC, Abelson murine leukemia viral oncogene homolog 1, TEC and C-terminal SRC Kinase families of non-receptor tyrosine kinases (collectively the Src module kinases) mediate an array of cellular signaling processes and are therapeutic targets in many disease states. Crystal structures of Src modules kinases provide valuable insights into the regulatory mechanisms that control activation and generate a framework from which drug discovery can advance. The conformational ensembles visited by these multidomain kinases in solution are also key features of the regulatory machinery controlling catalytic activity. Measurement of dynamic motions within kinases substantially augments information derived from crystal structures. In this review, we focus on a body of work that has transformed our understanding of non-receptor tyrosine kinase regulation from a static view to one that incorporates how fluctuations in conformational ensembles and dynamic motions influence activation status. Regulatory dynamic networks are often shared across and between kinase families while specific dynamic behavior distinguishes unique regulatory mechanisms for select kinases. Moreover, intrinsically dynamic regions of kinases likely play important regulatory roles that have only been partially explored. Since there is clear precedence that kinase inhibitors can exploit specific dynamic features, continued efforts to define conformational ensembles and dynamic allostery will be key to combating drug resistance and devising alternate treatments for kinase-associated diseases.

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22

Tan, J. L., and J. A. Spudich. "Developmentally regulated protein-tyrosine kinase genes in Dictyostelium discoideum." Molecular and Cellular Biology 10, no. 7 (July 1990): 3578–83. http://dx.doi.org/10.1128/mcb.10.7.3578-3583.1990.

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Dictyostelium discoideum, an organism that undergoes development and that is amenable to biochemical and molecular genetic approaches, is an attractive model organism with which to study the role of tyrosine phosphorylation in cell-cell communication. We report the presence of protein-tyrosine kinase genes in D. discoideum. Screening of a Dictyostelium cDNA expression library with an anti-phosphotyrosine antibody identifies fusion proteins that exhibit protein-tyrosine kinase activity. Two distinct cDNAs were identified and isolated. Though highly homologous to protein kinases in general, these kinases do not exhibit many of the hallmarks of protein-tyrosine kinases of higher eucaryotes. In addition, these genes are developmentally regulated, which suggests a role for tyrosine phosphorylation in controlling Dictyostelium development.

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23

Tan, J. L., and J. A. Spudich. "Developmentally regulated protein-tyrosine kinase genes in Dictyostelium discoideum." Molecular and Cellular Biology 10, no. 7 (July 1990): 3578–83. http://dx.doi.org/10.1128/mcb.10.7.3578.

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Dictyostelium discoideum, an organism that undergoes development and that is amenable to biochemical and molecular genetic approaches, is an attractive model organism with which to study the role of tyrosine phosphorylation in cell-cell communication. We report the presence of protein-tyrosine kinase genes in D. discoideum. Screening of a Dictyostelium cDNA expression library with an anti-phosphotyrosine antibody identifies fusion proteins that exhibit protein-tyrosine kinase activity. Two distinct cDNAs were identified and isolated. Though highly homologous to protein kinases in general, these kinases do not exhibit many of the hallmarks of protein-tyrosine kinases of higher eucaryotes. In addition, these genes are developmentally regulated, which suggests a role for tyrosine phosphorylation in controlling Dictyostelium development.

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24

Wen, X., H. H. Lin, and D. K. Ann. "Salivary Cellular Signaling and Gene Regulation." Advances in Dental Research 14, no. 1 (December 2000): 76–80. http://dx.doi.org/10.1177/08959374000140011201.

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Protein tyrosine kinase and protein serine kinase activation has been implicated in the regulation of salivary cell proliferation and differentiation. Aberrant expression and alterations of certain tyrosine or serine kinases, such as Raf or erbB2, are known to trigger salivary tumor development (Li et al., 1997; Cho et al., 1999). It has been estimated that there are about 1000 to 2000 protein kinases in the mammalian genome, with 100 to 200 of them ( i.e., 10%) being tyrosine kinase (Hanks and Hunter, 1995). At present, there are approximately 85 different tyrosine kinases identified in the GenBank database. Based on the relatively slow rate of discovery in the past few years, 100 is a better approximation of the total number of tyrosine kinases encoded by each mammalian genome. It is reasonable to assume that there are about 30 to 50 tyrosine kinases expressed in a given cell at a given differentiation/proliferation stage. This number is large enough to provide a characteristic tissue-specific tyrosine kinase expression profile, but small enough to be identified in a simple screening. The hope for tyrosine kinases as differentiation or proliferation markers rests with the possibility for the identification and characterization of a differentiation/proliferation stage-specific expression pattern in salivary cells. Several ligands that transmit signal through receptor tyrosine kinases and/or Ras/Raf/ERK kinases have been extensively studied in salivary cells. This review focuses mainly on the signaling pathways activated bv Raf and Etk.

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25

LANG, Mark L., Yih-Wen CHEN, Li SHEN, Hong GAO, Gillian A. LANG, Terri K. WADE, and William F. WADE. "IgA Fc receptor (FcαR) cross-linking recruits tyrosine kinases, phosphoinositide kinases and serine/threonine kinases to glycolipid rafts." Biochemical Journal 364, no. 2 (June 1, 2002): 517–25. http://dx.doi.org/10.1042/bj20011696.

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The human IgA Fc receptor (FcαR, CD89) triggers several important physiological functions, including phagocytosis, NADPH oxidase activation and antigen presentation. Efforts are underway to delineate FcαR signal-transduction pathways that control these functions. In a previous study, we demonstrated that cross-linking of FcαR increased its partitioning into membrane glycolipid rafts and was accompanied by γ-chain-dependent recruitment and phosphorylation of the tyrosine kinases Lck/Yes-related novel protein tyrosine kinase (Lyn) and Bruton's tyrosine kinase (Btk). Here we have performed a more extensive characterization of signalling effectors recruited to rafts on FcαR cross-linking. We demonstrate that in addition to tyrosine kinases Lyn and Btk, FcαR cross-linking also recruits B-lymphocyte kinase (Blk) and spleen tyrosine kinase (Syk) to rafts. We show recruitment of phosphoinositide kinases, including 3-phosphoinositide 3-kinase and phospholipase Cγ2, and serine/threonine kinases such as protein kinase C (PKC) α, PKC∊, and protein kinase B (PKB) α. This suggests that lipid rafts serve as sites for FcαR-triggered recruitment of multiple classes of signalling effectors. We further demonstrate that tyrosine kinases and PKCα have a sustained association with rafts, whereas phosphoinositide 3-kinase and its downstream effectors have a transient association with rafts. This is consistent with temporally regulated divergence of FcαR signalling pathways in rafts. Furthermore, we suggest the spatial separation of signalling effectors by transport of phosphoinositide 3-kinase, phosphoinositide-dependent kinase 1, PKBα and PKC∊ to endocytic compartments containing internalized FcαR.

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26

Dustin, Christopher M., David E. Heppner, Miao-Chong J. Lin, and Albert van der Vliet. "Redox regulation of tyrosine kinase signalling: more than meets the eye." Journal of Biochemistry 167, no. 2 (October 10, 2019): 151–63. http://dx.doi.org/10.1093/jb/mvz085.

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Abstract Protein kinases are essential mediators of cellular signal transduction and are often dysregulated in disease. Among these, protein tyrosine kinases (PTKs) have received specific interest due to their common roles in various diseases including cancer, and emerging observations indicating that PTK signalling pathways are susceptible to regulation by reactive oxygen species (ROS), which are also frequently implicated in disease pathology. While it is well recognized that ROS can impact on tyrosine kinase signalling by inhibiting tyrosine phosphatases, more recent studies highlight additional modes of redox-based regulation of tyrosine kinase signalling by direct redox modification of non-catalytic cysteines within tyrosine kinases or other protein components of this signalling pathway. In this review, we will present recent advancements with respect to redox-based mechanisms in regulating PTK signalling, with a specific focus on recent studies demonstrating direct redox regulation of Src-family kinases and epidermal growth factor receptor kinases. Importantly, redox-based modulation of tyrosine kinases may be relevant for many other kinases and has implications for current approaches to develop pharmacological inhibitors for these proteins.

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27

Kobayashi, Tomoko, Shun-Ichi Nakamura, and Hirohei Yamamura. "Cytosolic Protein-Tyrosine Kinase Activities in Various Rat Tissues." Annals of Clinical Biochemistry: International Journal of Laboratory Medicine 26, no. 2 (March 1989): 164–68. http://dx.doi.org/10.1177/000456328902600213.

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Suitable assay conditions for the detection of cytosolic protein-tyrosine kinase activities in crude extracts of various rat tissues have been determined. Cytosolic protein-tyrosine kinases showed common characteristics including substrate specificity and divalent cation requirement. Using (Val5) angiotensin II and Mn2+ rather than a src-related synthetic peptide, E11G1, and Mg2+, we obtained higher activities of cytosolic protein-tyrosine kinases. Among various rat tissues tested, spleen, bone marrow, thymus, small intestine, appendix and lung, in decreasing order of total activity, contained high activities of cytosolic protein-tyrosine kinases. These results suggest that the enzyme activities in lymphatic organs and in organs closely related to cell proliferation are high. The assay system described allows the precise measurement of cytosolic protein-tyrosine kinase activity in various rat tissues, both normal and malignant.

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BISOTTO, Sandra, and Elizabeth D. FIXMAN. "Src-family tyrosine kinases, phosphoinositide 3-kinase and Gab1 regulate extracellular signal-regulated kinase 1 activation induced by the type A endothelin-1 G-protein-coupled receptor." Biochemical Journal 360, no. 1 (November 8, 2001): 77–85. http://dx.doi.org/10.1042/bj3600077.

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The multisubstrate docking protein, growth-factor-receptor-bound protein 2-associated binder 1 (Gab1), which is phosphorylated on tyrosine residues following activation of receptor tyrosine kinases and cytokine receptors, regulates cell proliferation, survival and epithelial morphogenesis. Gab1 is also tyrosine phosphorylated following activation of G-protein-coupled receptors (GPCRs) where its function is poorly understood. To elucidate the role of Gab1 in GPCR signalling, we investigated the mechanism by which the type A endothelin-1 (ET-1) GPCR induced tyrosine phosphorylation of Gab1. Tyrosine phosphorylation of Gab1 induced by endothelin-1 was inhibited by PP1, a pharmacological inhibitor of Src-family tyrosine kinases. ET-1-induced Gab1 tyrosine phosphorylation was also inhibited by LY294002, which inhibits phosphoinositide 3-kinase (PI 3-kinase) enzymes. Inhibition of Src-family tyrosine kinases or PI 3-kinase also inhibited ET-1-induced activation of the mitogen activated protein kinase family member, extracellular signal-regulated kinase (ERK) 1. Thus we determined whether Gab1 regulated ET-1-induced ERK1 activation. Overexpression of wild-type Gab1 potentiated ET-1-induced activation of ERK1. Structure–function analyses of Gab1 indicated that mutant forms of Gab1 that do not bind the Src homology (SH) 2 domains of the p85 adapter subunit of PI 3-kinase or the SH2-domain-containing protein tyrosine phosphatase 2 (SHP-2) were impaired in their ability to potentiate ET-1-induced ERK1 activation. Taken together, our data indicate that PI 3-kinase and Src-family tyrosine kinases regulate ET-1-induced Gab1 tyrosine phosphorylation, which, in turn, induces ERK1 activation via PI 3-kinase- and SHP-2-dependent pathways.

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29

Bach, Horacio, Dennis Wong, and Yossef Av-Gay. "Mycobacterium tuberculosis PtkA is a novel protein tyrosine kinase whose substrate is PtpA." Biochemical Journal 420, no. 2 (May 13, 2009): 155–62. http://dx.doi.org/10.1042/bj20090478.

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In Mycobacterium tuberculosis, signal transduction is mediated by 11 serine/threonine kinases, but no tyrosine kinases have been identified thus far. The protein encoded by the ORF (open reading frame) Rv2232 has been annotated as a member of the HAD (haloacid dehydrogenase-like hydrolase) superfamily, which includes phosphatases, phosphomanno- and phosphogluco-mutases, and haloacid dehydrogenases. In the present paper, we report, on the basis of biochemical and mutational analyses, that the Rv2232-encoded protein, named protein tyrosine kinase A (PtkA) is a bona fide protein tyrosine kinase. The cognate substrate of PtkA is the secreted protein tyrosine phosphatase A (PtpA).

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30

Fabian, J. R., I. O. Daar, and D. K. Morrison. "Critical tyrosine residues regulate the enzymatic and biological activity of Raf-1 kinase." Molecular and Cellular Biology 13, no. 11 (November 1993): 7170–79. http://dx.doi.org/10.1128/mcb.13.11.7170-7179.1993.

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The serine/threonine kinase activity of the Raf-1 proto-oncogene product is stimulated by the activation of many tyrosine kinases, including growth factor receptors and pp60v-src. Recent studies of growth factor signal transduction pathways demonstrate that Raf-1 functions downstream of activated tyrosine kinases and p21ras and upstream of mitogen-activated protein kinase. However, coexpression of both activated tyrosine kinases and p21ras is required for maximal activation of Raf-1 in the baculovirus-Sf9 expression system. In this study, we investigated the role of tyrosine kinases and tyrosine phosphorylation in the regulation of Raf-1 activity. Using the baculovirus-Sf9 expression system, we identified Tyr-340 and Tyr-341 as the major tyrosine phosphorylation sites of Raf-1 when coexpressed with activated tyrosine kinases. Introduction of a negatively charged residue that may mimic the effect of phosphorylation at these sites activated the catalytic activity of Raf-1 and generated proteins that could transform BALB/3T3 cells and induce the meiotic maturation of Xenopus oocytes. In contrast, substitution of noncharged residues that were unable to be phosphorylated produced a protein that could not be enzymatically activated by tyrosine kinases and that could block the meiotic maturation of oocytes induced by components of the receptor tyrosine kinase pathway. These findings demonstrate that maturation of the tyrosine phosphorylation sites can dramatically alter the function of Raf-1. In addition, this is the first report that a transforming Raf-1 protein can be generated by a single amino acid substitution.

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Fabian, J. R., I. O. Daar, and D. K. Morrison. "Critical tyrosine residues regulate the enzymatic and biological activity of Raf-1 kinase." Molecular and Cellular Biology 13, no. 11 (November 1993): 7170–79. http://dx.doi.org/10.1128/mcb.13.11.7170.

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The serine/threonine kinase activity of the Raf-1 proto-oncogene product is stimulated by the activation of many tyrosine kinases, including growth factor receptors and pp60v-src. Recent studies of growth factor signal transduction pathways demonstrate that Raf-1 functions downstream of activated tyrosine kinases and p21ras and upstream of mitogen-activated protein kinase. However, coexpression of both activated tyrosine kinases and p21ras is required for maximal activation of Raf-1 in the baculovirus-Sf9 expression system. In this study, we investigated the role of tyrosine kinases and tyrosine phosphorylation in the regulation of Raf-1 activity. Using the baculovirus-Sf9 expression system, we identified Tyr-340 and Tyr-341 as the major tyrosine phosphorylation sites of Raf-1 when coexpressed with activated tyrosine kinases. Introduction of a negatively charged residue that may mimic the effect of phosphorylation at these sites activated the catalytic activity of Raf-1 and generated proteins that could transform BALB/3T3 cells and induce the meiotic maturation of Xenopus oocytes. In contrast, substitution of noncharged residues that were unable to be phosphorylated produced a protein that could not be enzymatically activated by tyrosine kinases and that could block the meiotic maturation of oocytes induced by components of the receptor tyrosine kinase pathway. These findings demonstrate that maturation of the tyrosine phosphorylation sites can dramatically alter the function of Raf-1. In addition, this is the first report that a transforming Raf-1 protein can be generated by a single amino acid substitution.

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K. Bhanumathy, Kalpana, Amrutha Balagopal, Frederick S. Vizeacoumar, Franco J. Vizeacoumar, Andrew Freywald, and Vincenzo Giambra. "Protein Tyrosine Kinases: Their Roles and Their Targeting in Leukemia." Cancers 13, no. 2 (January 7, 2021): 184. http://dx.doi.org/10.3390/cancers13020184.

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Protein kinases constitute a large group of enzymes catalysing protein phosphorylation and controlling multiple signalling events. The human protein kinase superfamily consists of 518 members and represents a complicated system with intricate internal and external interactions. Protein kinases are classified into two main families based on the ability to phosphorylate either tyrosine or serine and threonine residues. Among the 90 tyrosine kinase genes, 58 are receptor types classified into 20 groups and 32 are of the nonreceptor types distributed into 10 groups. Tyrosine kinases execute their biological functions by controlling a variety of cellular responses, such as cell division, metabolism, migration, cell–cell and cell matrix adhesion, cell survival and apoptosis. Over the last 30 years, a major focus of research has been directed towards cancer-associated tyrosine kinases owing to their critical contributions to the development and aggressiveness of human malignancies through the pathological effects on cell behaviour. Leukaemia represents a heterogeneous group of haematological malignancies, characterised by an uncontrolled proliferation of undifferentiated hematopoietic cells or leukaemia blasts, mostly derived from bone marrow. They are usually classified as chronic or acute, depending on the rates of their progression, as well as myeloid or lymphoblastic, according to the type of blood cells involved. Overall, these malignancies are relatively common amongst both children and adults. In malignant haematopoiesis, multiple tyrosine kinases of both receptor and nonreceptor types, including AXL receptor tyrosine kinase (AXL), Discoidin domain receptor 1 (DDR1), Vascular endothelial growth factor receptor (VEGFR), Fibroblast growth factor receptor (FGFR), Mesenchymal–epithelial transition factor (MET), proto-oncogene c-Src (SRC), Spleen tyrosine kinase (SYK) and pro-oncogenic Abelson tyrosine-protein kinase 1 (ABL1) mutants, are implicated in the pathogenesis and drug resistance of practically all types of leukaemia. The role of ABL1 kinase mutants and their therapeutic inhibitors have been extensively analysed in scientific literature, and therefore, in this review, we provide insights into the impact and mechanism of action of other tyrosine kinases involved in the development and progression of human leukaemia and discuss the currently available and emerging treatment options based on targeting these molecules.

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K. Bhanumathy, Kalpana, Amrutha Balagopal, Frederick S. Vizeacoumar, Franco J. Vizeacoumar, Andrew Freywald, and Vincenzo Giambra. "Protein Tyrosine Kinases: Their Roles and Their Targeting in Leukemia." Cancers 13, no. 2 (January 7, 2021): 184. http://dx.doi.org/10.3390/cancers13020184.

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Protein kinases constitute a large group of enzymes catalysing protein phosphorylation and controlling multiple signalling events. The human protein kinase superfamily consists of 518 members and represents a complicated system with intricate internal and external interactions. Protein kinases are classified into two main families based on the ability to phosphorylate either tyrosine or serine and threonine residues. Among the 90 tyrosine kinase genes, 58 are receptor types classified into 20 groups and 32 are of the nonreceptor types distributed into 10 groups. Tyrosine kinases execute their biological functions by controlling a variety of cellular responses, such as cell division, metabolism, migration, cell–cell and cell matrix adhesion, cell survival and apoptosis. Over the last 30 years, a major focus of research has been directed towards cancer-associated tyrosine kinases owing to their critical contributions to the development and aggressiveness of human malignancies through the pathological effects on cell behaviour. Leukaemia represents a heterogeneous group of haematological malignancies, characterised by an uncontrolled proliferation of undifferentiated hematopoietic cells or leukaemia blasts, mostly derived from bone marrow. They are usually classified as chronic or acute, depending on the rates of their progression, as well as myeloid or lymphoblastic, according to the type of blood cells involved. Overall, these malignancies are relatively common amongst both children and adults. In malignant haematopoiesis, multiple tyrosine kinases of both receptor and nonreceptor types, including AXL receptor tyrosine kinase (AXL), Discoidin domain receptor 1 (DDR1), Vascular endothelial growth factor receptor (VEGFR), Fibroblast growth factor receptor (FGFR), Mesenchymal–epithelial transition factor (MET), proto-oncogene c-Src (SRC), Spleen tyrosine kinase (SYK) and pro-oncogenic Abelson tyrosine-protein kinase 1 (ABL1) mutants, are implicated in the pathogenesis and drug resistance of practically all types of leukaemia. The role of ABL1 kinase mutants and their therapeutic inhibitors have been extensively analysed in scientific literature, and therefore, in this review, we provide insights into the impact and mechanism of action of other tyrosine kinases involved in the development and progression of human leukaemia and discuss the currently available and emerging treatment options based on targeting these molecules.

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Gold, M. R., J. S. Sanghera, J. Stewart, and S. L. Pelech. "Selective activation of p42 mitogen-activated protein (MAP) kinase in murine B lymphoma cell lines by membrane immunoglobulin cross-linking. Evidence for protein kinase C-independent and -dependent mechanisms of activation." Biochemical Journal 287, no. 1 (October 1, 1992): 269–76. http://dx.doi.org/10.1042/bj2870269.

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Cross-linking of membrane immunoglobulin (mIg), the B lymphocyte antigen receptor, with anti-receptor antibodies stimulates tyrosine phosphorylation of a number of proteins, including one of 42 kDa. Proteins with a similar molecular mass are tyrosine-phosphorylated in response to receptor stimulation in other cell types and have been identified as serine/threonine kinases, termed mitogen-activated protein (MAP) kinases or extracellular signal-regulated kinases (ERKs). The MAP kinases constitute a family of related kinases, at least three of which have molecular masses of 40-45 kDa. In this paper we show that mIg cross-linking stimulated the myelin basic protein phosphotransferase activity characteristic of MAP kinase in both mature and immature murine B cell lines. This enzyme activity co-purified on three different columns with a 42 kDa protein that was tyrosine-phosphorylated (pp42) in response to mIg cross-linking and which reacted with a panel of anti-(MAP kinase) antibodies. Although immunoblotting with the anti-(MAP kinase) antibodies showed that these B cell lines expressed both 42 kDa and 44 kDa forms of MAP kinase, only the 42 kDa form was activated and tyrosine-phosphorylated to a significant extent. Activation of protein kinase C (PKC) with phorbol esters also resulted in selective tyrosine phosphorylation and activation of the 42 kDa MAP kinase. This suggested that mIg-induced MAP kinase activation could be due to stimulation of PKC by mIg. However, mIg-stimulated MAP kinase activation and pp42 tyrosine phosphorylation was only partially blocked by a PKC inhibitor, the staurosporine analogue Compound 3. In contrast, Compound 3 completely blocked the ability of phorbol esters to stimulate MAP kinase activity and induce tyrosine phosphorylation of pp42. Thus mIg may activate MAP kinase by both PKC-dependent and -independent mechanisms.

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Lin, J., and L. B. Justement. "The MB-1/B29 heterodimer couples the B cell antigen receptor to multiple src family protein tyrosine kinases." Journal of Immunology 149, no. 5 (September 1, 1992): 1548–55. http://dx.doi.org/10.4049/jimmunol.149.5.1548.

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Abstract The B cell Ag receptor complex is comprised of membrane (m)IgM or mIgD noncovalently associated with one or more heterodimers, each containing one subunit of MB-1 (IgM alpha or IgD alpha) and one of B29 (Ig beta or Ig gamma). It is known that cross-linking of the B cell Ag receptor results in protein tyrosine kinase activation. Recent reports from other laboratories have demonstrated that mIg coprecipitates with multiple src family protein tyrosine kinases, including blk, lyn, and fyn. However, the mechanism by which these kinases are physically coupled to the Ag receptor has not been confirmed. It has been hypothesized that the mIg-associated proteins MB-1 and B29 provide a physical link between the Ag receptor (mIg) and one or more protein tyrosine kinases. In this study, we confirm previous findings demonstrating that the B cell Ag receptor coprecipitates with the MB-1/B29 heterodimer as well as the protein tyrosine kinases blk, lyn, and fyn under mild detergent conditions (1% digitonin). Additionally, we demonstrate that in detergent conditions (1% Nonidet P-40 (NP-40)) which disrupt the association between mIg and the MB-1/B29 heterodimer, no protein tyrosine kinase activity can be detected in association with mIg. These findings indicated that NP-40 effectively dissociates the B cell Ag receptor from ancillary signal transducing proteins. MB-1 and B29 were however, found to coprecipitate with blk, lyn, and fyn isolated from B cell lysates containing 1% NP-40. No significant difference was observed in the stoichiometry of association between the kinases and the MB-1/B29 heterodimer in the presence of 1% NP-40 when compared to 1% digitonin. It was further determined that in resting B cells, only a small fraction (approximately 1-3%) of the MB-1/B29 heterodimers appear to be complexed with protein tyrosine kinases. Finally, based on preclearing experiments, it appears that individual heterodimers may associate with a single species of protein tyrosine kinase. These data support the hypothesis that the MB-1/B29 heterodimer couples the antigen receptor to protein tyrosine kinases, thereby providing a physical link that facilitates Ag receptor-mediated regulation of kinase activity.

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MULLAPUDI, Srinivas R. S., Francis ALI-OSMAN, Jiang SHOU, and Kalkunte S. SRIVENUGOPAL. "DNA repair protein O6-alkylguanine-DNA alkyltransferase is phosphorylated by two distinct and novel protein kinases in human brain tumour cells." Biochemical Journal 351, no. 2 (October 10, 2000): 393–402. http://dx.doi.org/10.1042/bj3510393.

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We showed recently that human O6-alkylguanine-DNA alkyltransferase (AGT), an important target for improving cancer chemotherapy, is a phosphoprotein and that phosphorylation inhibits its activity [Srivenugopal, Mullapudi, Shou, Hazra and Ali-Osman (2000) Cancer Res. 60, 282–287]. In the present study we characterized the cellular kinases that phosphorylate AGT in the human medulloblastoma cell line HBT228. Crude cell extracts used Mg2+ more efficiently than Mn2+ for phosphorylating human recombinant AGT (rAGT) protein. Both [γ-32P]ATP and [γ-32P]GTP served as phosphate donors, with the former being twice as efficient. Specific components known to activate protein kinase A, protein kinase C and calmodulin-dependent kinases did not stimulate the phosphorylation of rAGT. Phosphoaminoacid analysis after reaction in vitro with ATP or GTP showed that AGT was modified at the same amino acids (serine, threonine and tyrosine) as in intact HBT228 cells. Although some of these properties pointed to casein kinase II as a candidate enzyme, known inhibitors and activators of casein kinase II did not affect rAGT phosphorylation. Fractionation of the cell extracts on poly(Glu/Tyr)-Sepharose resulted in the adsorption of an AGT kinase that modified the tyrosine residues and the exclusion of a fraction that phosphorylated AGT on serine and threonine residues. In-gel kinase assays after SDS/PAGE and non-denaturing PAGE revealed the presence of two AGT kinases of 75 and 130kDa in HBT228 cells. The partly purified tyrosine kinase, identified as the 130kDa enzyme by the same assays, was strongly inhibited by tyrphostin 25 but not by genestein. The tyrosine kinase used ATP or GTP to phosphorylate the AGT protein; this reaction inhibited the DNA repair activity of AGT. Evidence that the kinases might physically associate with AGT in cells was also provided. These results demonstrate that two novel cellular protein kinases, a tyrosine kinase and a serine/threonine kinase, both capable of using GTP as a donor, phosphorylate the AGT protein and affect its function. The new kinases might serve as potential targets for strengthening the biochemical modulation of AGT in human tumours.

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Sun, Yongjun, You Chen, Liying Zhan, Linan Zhang, Jie Hu, and Zibin Gao. "The role of non-receptor protein tyrosine kinases in the excitotoxicity induced by the overactivation of NMDA receptors." Reviews in the Neurosciences 27, no. 3 (April 1, 2016): 283–89. http://dx.doi.org/10.1515/revneuro-2015-0037.

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AbstractProtein tyrosine phosphorylation is one of the primary modes of regulation of N-methyl-d-aspartate (NMDA) receptors. The non-receptor tyrosine kinases are one of the two types of protein tyrosine kinases that are involved in this process. The overactivation of NMDA receptors is a primary reason for neuron death following cerebral ischemia. Many studies have illustrated the important role of non-receptor tyrosine kinases in ischemia insults. This review introduces the roles of Src, Fyn, focal adhesion kinase, and proline-rich tyrosine kinase 2 in the excitotoxicity induced by the overactivation of NMDA receptors following cerebral ischemia.

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Tsygankov, Alexander Y. "Non-receptor protein tyrosine kinases." Frontiers in Bioscience 8, no. 6 (2003): s595–635. http://dx.doi.org/10.2741/1106.

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Kolibaba, Kathryn S., and Brian J. Druker. "Protein tyrosine kinases and cancer." Biochimica et Biophysica Acta (BBA) - Reviews on Cancer 1333, no. 3 (December 1997): F217—F248. http://dx.doi.org/10.1016/s0304-419x(97)00022-x.

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Fry, David W., and Alexander J. Bridges. "Inhibitors of protein tyrosine kinases." Current Opinion in Biotechnology 6, no. 6 (January 1995): 662–67. http://dx.doi.org/10.1016/0958-1669(95)80109-x.

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Trojanek, Joanna B., Maria M. Klimecka, Anna Fraser, Grazyna Dobrowolska, and Grazyna Muszyńska. "Characterization of dual specificity protein kinase from maize seedlings." Acta Biochimica Polonica 51, no. 3 (September 30, 2004): 635–47. http://dx.doi.org/10.18388/abp.2004_3549.

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A protein kinase of 57 kDa, able to phosphorylate tyrosine in synthetic substrates pol(Glu4,Tyr1) and a fragment of Src tyrosine kinase, was isolated and partly purified from maize seedlings (Zea mays). The protein kinase was able to phosphorylate exogenous proteins: enolase, caseins, histones and myelin basic protein. Amino acid analysis of phosphorylated casein and enolase, as well as of phosphorylated endogenous proteins, showed that both Tyr and Ser residues were phosphorylated. Phosphotyrosine was also immunodetected in the 57 kDa protein fraction. In the protein fraction there are present 57 kDa protein kinase and enolase. This co-purification suggests that enolase can be an endogenous substrate of the kinase. The two proteins could be resolved by two-dimensional electrophoresis. Specific inhibitors of typical protein-tyrosine kinases had essentially no effect on the activity of the maize enzyme. Staurosporine, a nonspecific inhibitor of protein kinases, effectively inhibited the 57 kDa protein kinase. Also, poly L-lysine and heparin inhibited tyrosine phosphorylation by 57 kDa maize protein kinase. The substrate and inhibitor specificities of the 57 kDa maize protein kinase phosphorylating tyrosine indicate that it is a novel plant dual-specificity protein kinase.

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Rane, M. J., S. L. Carrithers, J. M. Arthur, J. B. Klein, and K. R. McLeish. "Formyl peptide receptors are coupled to multiple mitogen-activated protein kinase cascades by distinct signal transduction pathways: role in activation of reduced nicotinamide adenine dinucleotide oxidase." Journal of Immunology 159, no. 10 (November 15, 1997): 5070–78. http://dx.doi.org/10.4049/jimmunol.159.10.5070.

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Abstract Formyl peptide receptor activation of three mitogen-activated protein kinase (MAPK) cascades, extracellular signal-regulated kinases (ERKs), N-terminal kinases (JNKs), and p38 MAPK was examined in differentiated HL-60 granulocytes. FMLP stimulated a concentration- and time-dependent increase in ERK, JNK, and p38 MAPK activities, all of which were dependent on a pertussis toxin-sensitive G protein. Pharmacologic inhibitors were used to examine the roles of tyrosine kinases, phosphatidylinositol 3-kinase, protein kinase C, and phospholipase C. FMLP-stimulated ERK activity was dependent on tyrosine kinases, phosphatidylinositol 3-kinase, protein kinase C, and phospholipase C; p38 MAPK activation was dependent on phosphatidylinositol 3-kinase and phospholipase C; while JNK activation was independent of all of these signaling components. The mitogen-activated protein kinase/ERK kinase inhibitor PD098059 reduced ERK activation by 90%, while an inhibitor of p38 MAPK, SB203580, inhibited p38 MAPK activation by 80%. Both PD098059 and SB203580 inhibited FMLP-stimulated superoxide release, as did inhibitors directed against protein kinase C, tyrosine kinases, and phosphatidylinositol 3-kinase. We conclude that formyl peptide receptors are coupled to three MAPK cascades by Gi proteins. ERKs, p38 MAPK, and JNKs are each activated by distinct proximal signal transduction pathways. Activation of p38 MAPK is necessary for FMLP stimulation of respiratory burst activity; however, a second signal that may involve ERK is also required for this activity.

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Bauer, Markus, Petra Maschberger, Lynn Quek, Stephen Briddon, Debabrata Dash, Michael Weiss, Steve Watson, and Wolfgang Siess. "Genetic and Pharmacological Analyses of Involvement of Src-family, Syk and Btk Tyrosine Kinases in Platelet Shape Change." Thrombosis and Haemostasis 85, no. 02 (2001): 331–40. http://dx.doi.org/10.1055/s-0037-1615689.

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SummaryPlatelet shape change was found to be associated with an increase in protein tyrosine phosphorylation upon stimulation of thrombin-, ADPand thromboxane A2-G-protein coupled receptors in human platelets and thromboxane A2 receptors in mouse platelets. By using PP1 and PD173956, two structurally unrelated specific inhibitors of Src-family tyrosine kinases, and mouse platelets deficient in the Src-kinase Fyn or Lyn, we show that Src-family kinases cause the increase in protein tyrosine phosphorylation. We further detected that the non-Src tyrosine kinase Syk was activated during shape change in a manner dependent on Src-family kinaseactivation. The pharmacological experiments and the studies on Fyn-, Lyn- and Syk-deficient mouse platelets showed that neither Src-family kinases nor Syk are functionally involved in shape change. Also human platelets deficient of the tyrosine kinase Btk showed a normal shape change. Binding of PAC-1 that recognizes activated integrin αIIb β3 complexes on the platelet surface was enhanced during shape change and blocked by inhibition of Src-kinases. We conclude that the activation of Src-kinases and the subsequent Syk stimulation upon activation of G-protein coupled receptors are not involved in the cytoskeletal changes underlying shape change of human and mouse platelets, but that the stimulation of this evolutionary conserved pathway leads to integrin αIIb β3 exposure during shape change.

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Purcell, Angela L., and Thomas J. Carew. "Modulation of Excitability in Aplysia Tail Sensory Neurons by Tyrosine Kinases." Journal of Neurophysiology 85, no. 6 (June 1, 2001): 2398–411. http://dx.doi.org/10.1152/jn.2001.85.6.2398.

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Tyrosine kinases have recently been shown to modulate synaptic plasticity and ion channel function. We show here that tyrosine kinases can also modulate both the baseline excitability state of Aplysia tail sensory neurons (SNs) as well as the excitability induced by the neuromodulator serotonin (5HT). First, we examined the effects of increasing and decreasing tyrosine kinase activity in the SNs. We found that tyrosine kinase inhibitors decrease baseline SN excitability in addition to attenuating the increase in excitability induced by 5HT. Conversely, functionally increasing cellular tyrosine kinase activity in the SNs by either inhibiting opposing tyrosine phosphatase activity or by direct injection of an active tyrosine kinase (Src) induces increases in SN excitability in the absence of 5HT. Second, we examined the interaction between protein kinase A (PKA), which is known to mediate 5HT-induced excitability changes in the SNs, and tyrosine kinases, in the enhancement of SN excitability. We found that the tyrosine kinases function downstream of PKA activation since tyrosine kinase inhibitors reduce excitability induced by activators of PKA. Finally, we examined the role of tyrosine kinases in other forms of 5HT-induced plasticity in the SNs. We found that while tyrosine kinase inhibitors attenuate excitability produced by 5HT, they have no effect on short-term facilitation (STF) of the SN-motor neuron (MN) synapse induced by 5HT. Thus tyrosine kinases modulate different forms of SN plasticity independently. Such differential modulation would have important consequences for activity-dependent plasticity in a variety of neural circuits.

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Pawson, T., K. Letwin, T. Lee, Q. L. Hao, N. Heisterkamp, and J. Groffen. "The FER gene is evolutionarily conserved and encodes a widely expressed member of the FPS/FES protein-tyrosine kinase family." Molecular and Cellular Biology 9, no. 12 (December 1989): 5722–25. http://dx.doi.org/10.1128/mcb.9.12.5722-5725.1989.

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We have recently isolated human and rat cDNAs (designated FER and flk, respectively) which encode nonreceptor protein-tyrosine kinases which are very similar to one another and related in sequence and domain structure to the c-fps/fes gene product. We show that FER and flk are human and rat counterparts of an evolutionarily conserved gene, hereafter termed FER regardless of species. The human and rat FER genes encode a widely expressed 94-kilodalton protein-tyrosine kinase which is antigenically related to the fps/fes protein-tyrosine kinase. The structural and antigenic similarities between the FER and fps/fes proteins suggest that they are members of a new family of nonreceptor protein-tyrosine kinases.

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46

Pawson, T., K. Letwin, T. Lee, Q. L. Hao, N. Heisterkamp, and J. Groffen. "The FER gene is evolutionarily conserved and encodes a widely expressed member of the FPS/FES protein-tyrosine kinase family." Molecular and Cellular Biology 9, no. 12 (December 1989): 5722–25. http://dx.doi.org/10.1128/mcb.9.12.5722.

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We have recently isolated human and rat cDNAs (designated FER and flk, respectively) which encode nonreceptor protein-tyrosine kinases which are very similar to one another and related in sequence and domain structure to the c-fps/fes gene product. We show that FER and flk are human and rat counterparts of an evolutionarily conserved gene, hereafter termed FER regardless of species. The human and rat FER genes encode a widely expressed 94-kilodalton protein-tyrosine kinase which is antigenically related to the fps/fes protein-tyrosine kinase. The structural and antigenic similarities between the FER and fps/fes proteins suggest that they are members of a new family of nonreceptor protein-tyrosine kinases.

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Gutkind, J. S., P. M. Lacal, and K. C. Robbins. "Thrombin-dependent association of phosphatidylinositol-3 kinase with p60c-src and p59fyn in human platelets." Molecular and Cellular Biology 10, no. 7 (July 1990): 3806–9. http://dx.doi.org/10.1128/mcb.10.7.3806-3809.1990.

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Recent studies have shown that ligand-activated growth factor receptors as well as transforming versions of nonreceptor protein-tyrosine kinases physically associate with phosphatidylinositol-3 kinase (PI-3 kinase). Reasoning that PI-3 kinase might also play a role in the normal functions of nonreceptor kinases, we sought to determine whether association with PI-3 kinase might serve as a measure of nonreceptor protein-tyrosine kinase activation under physiological conditions. We found that p60c-src as well as p59fyn, the product of another member of the src family of proto-oncogenes, physically associated with a PI kinase activity within 5 s after exposure to thrombin. Furthermore, PI kinase reaction products generated in p60v-src, p60c-src or p59fyn containing immunoprecipitates were indistinguishable, demonstrating the identity of the associated enzyme as PI-3 kinase. These findings demonstrate a thrombin-dependent interaction between p60c-src or p59fyn and PI-3 kinase and suggest a role for nonreceptor protein-tyrosine kinases in human platelet signal transduction.

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48

Gutkind, J. S., P. M. Lacal, and K. C. Robbins. "Thrombin-dependent association of phosphatidylinositol-3 kinase with p60c-src and p59fyn in human platelets." Molecular and Cellular Biology 10, no. 7 (July 1990): 3806–9. http://dx.doi.org/10.1128/mcb.10.7.3806.

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Recent studies have shown that ligand-activated growth factor receptors as well as transforming versions of nonreceptor protein-tyrosine kinases physically associate with phosphatidylinositol-3 kinase (PI-3 kinase). Reasoning that PI-3 kinase might also play a role in the normal functions of nonreceptor kinases, we sought to determine whether association with PI-3 kinase might serve as a measure of nonreceptor protein-tyrosine kinase activation under physiological conditions. We found that p60c-src as well as p59fyn, the product of another member of the src family of proto-oncogenes, physically associated with a PI kinase activity within 5 s after exposure to thrombin. Furthermore, PI kinase reaction products generated in p60v-src, p60c-src or p59fyn containing immunoprecipitates were indistinguishable, demonstrating the identity of the associated enzyme as PI-3 kinase. These findings demonstrate a thrombin-dependent interaction between p60c-src or p59fyn and PI-3 kinase and suggest a role for nonreceptor protein-tyrosine kinases in human platelet signal transduction.

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Childs, Timothy J., and Alan S. Mak. "MAP kinases from bovine brain: purification and characterization." Biochemistry and Cell Biology 71, no. 11-12 (December 1, 1993): 544–55. http://dx.doi.org/10.1139/o93-078.

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We have purified 42- and 44-kilodalton (kDa) isoforms of the mitogen-activated protein (MAP) kinase family from bovine brain. The kinases were assayed with myelin basic protein as the substrate and detected by anti-sea star p44mpk antibody. Purification was achieved using phenyl-Sepharose, polylysine–agarose, hydroxylapatite, and Mono-Q column chromatography. Both myelin basic protein and smooth muscle caldesmon, but not histone H1, served as good substrates. Based on chromatographic behaviors and specific activities toward myelin basic protein, it is likely that the 42-kDa brain isoform is similar to that of brain tau kinase. The 44-kDa enzyme, however, is a novel brain MAP kinase isoform not reported previously. Although it has been demonstrated that p44mpk can be activated in vitro through phosphorylation by the tyrosine kinase p56lck, neither of the brain kinases were significantly stimulated by the tyrosine kinases p56lck, p56lyn, or p59fyn. However, based on antibody cross-reactivity, a MAP kinase kinase is present in the crude brain extract. Both brain MAP kinases were capable of autophosphorylation which occurred, at least in part, on tyrosine residues. However, only the 44-kDa isoform showed a significant degree of coincident activation.Key words: brain, MAP kinase, purification.

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Pleiman, C. M., M. R. Clark, L. K. Gauen, S. Winitz, K. M. Coggeshall, G. L. Johnson, A. S. Shaw, and J. C. Cambier. "Mapping of sites on the Src family protein tyrosine kinases p55blk, p59fyn, and p56lyn which interact with the effector molecules phospholipase C-gamma 2, microtubule-associated protein kinase, GTPase-activating protein, and phosphatidylinositol 3-kinase." Molecular and Cellular Biology 13, no. 9 (September 1993): 5877–87. http://dx.doi.org/10.1128/mcb.13.9.5877-5887.1993.

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Engagement of the B-cell antigen receptor complex induces immediate activation of receptor-associated Src family tyrosine kinases including p55blk, p59fyn, p53/56lyn, and perhaps p56lck, and this response is accompanied by tyrosine phosphorylation of distinct cellular substrates. These kinases act directly or indirectly to phosphorylate and/or activate effector proteins including p42 (microtubule-associated protein kinase) (MAPK), phospholipases C-gamma 1 (PLC gamma 1) and C-gamma 2 (PLC gamma 2), phosphatidylinositol 3-kinase (PI 3-K), and p21ras-GTPase-activating protein (GAP). Although coimmunoprecipitation results indicate that the Src family protein tyrosine kinases interact physically with some of these effector molecules, the molecular basis of this interaction has not been established. Here, we show that three distinct sites mediate the interaction of these kinases with effectors. The amino-terminal 27 residues of the unique domain of p56lyn mediate association with PLC gamma 2, MAPK, and GAP. Binding to PI 3-K is mediated through the Src homology 3 (SH3) domains of the Src family kinases. Relatively small proportions of cellular PI 3-K, PLC gamma 2, MAPK, and GAP, presumably those which are tyrosine phosphorylated, bind to the SH2 domains of these kinases. Comparative analysis of binding activities of Blk, Lyn, and Fyn shows that these kinases differ in their abilities to associate with MAPK and PI 3-K, suggesting that they may preferentially bind and subsequently phosphorylate distinct sets of downstream effector molecules in vivo. Fast protein liquid chromatography Mono Q column-fractionated MAPK maintains the ability to bind bacterially expressed Lyn, suggesting that the two kinases may interact directly.

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Journal articles on the topic 'Protein-tyrosine kinases'

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