Journal articles on the topic 'Protein kinase'

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1

Pang, Kam-Lee, Wei-Li Thong, and Siew-Eng How. "Cinnamomum Iners as Mitogen-Activated Protein Kinase Kinase (MKK1) Inhibitor." International Journal of Engineering and Technology 1, no. 4 (2009): 310–13. http://dx.doi.org/10.7763/ijet.2009.v1.61.

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2

Frost, J. A., S. Xu, M. R. Hutchison, S. Marcus, and M. H. Cobb. "Actions of Rho family small G proteins and p21-activated protein kinases on mitogen-activated protein kinase family members." Molecular and Cellular Biology 16, no. 7 (July 1996): 3707–13. http://dx.doi.org/10.1128/mcb.16.7.3707.

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The mitogen-activated protein (MAP) kinases are a family of serine/threonine kinases that are regulated by distinct extracellular stimuli. The currently known members include extracellular signal-regulated protein kinase 1 (ERK1), ERK2, the c-Jun N-terminal kinase/stress-activated protein kinases (JNK/SAPKs), and p38 MAP kinases. We find that overexpression of the Ste20-related enzymes p21-activated kinase 1 (PAK1) and PAK2 in 293 cells is sufficient to activate JNK/SAPK and to a lesser extent p38 MAP kinase but not ERK2. Rat MAP/ERK kinase kinase 1 can stimulate the activity of each of these MAP kinases. Although neither activated Rac nor the PAKs stimulate ERK2 activity, overexpression of either dominant negative Rac2 or the N-terminal regulatory domain of PAK1 inhibits Ras-mediated activation of ERK2, suggesting a permissive role for Rac in the control of the ERK pathway. Furthermore, constitutively active Rac2, Cdc42hs, and RhoA synergize with an activated form of Raf to increase ERK2 activity. These findings reveal a previously unrecognized connection between Rho family small G proteins and the ERK pathway.
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3

Luise, M., C. Presotto, L. Senter, R. Betto, S. Ceoldo, S. Furlan, S. Salvatori, R. A. Sabbadini, and G. Salviati. "Dystrophin is phosphorylated by endogenous protein kinases." Biochemical Journal 293, no. 1 (July 1, 1993): 243–47. http://dx.doi.org/10.1042/bj2930243.

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Dystrophin, the protein coded by the gene missing in Duchenne muscular dystrophy, is assumed to be a component of the membrane cytoskeleton of skeletal muscle. Like other cytoskeletal proteins in different cell types, dystrophin bound to sarcolemma membranes was found to be phosphorylated by endogenous protein kinases. The phosphorylation of dystrophin was activated by cyclic AMP, cyclic GMP, calcium and calmodulin, and was inhibited by cyclic AMP-dependent protein kinase peptide inhibitor, mastoparan and heparin. These results suggest that membrane-bound dystrophin is a substrate of endogenous cyclic AMP- and cyclic GMP-dependent protein kinases, calcium/calmodulin-dependent kinase and casein kinase II. The possibility that dystrophin could be phosphorylated by protein kinase C is suggested by the inhibition of phosphorylation by staurosporin. On the other hand dystrophin seems not to be a substrate for protein tyrosine kinases, as shown by the lack of reaction of phosphorylated dystrophin with a monoclonal antiphosphotyrosine antibody. Sequence analysis indicates that dystrophin contains seven potential phosphorylation sites for cyclic AMP- and cyclic GMP-dependent protein kinases (all localized in the central rod domain of the molecule) as well as several sites for protein kinase C and casein kinase II. Interestingly, potential sites of phosphorylation by protein kinase C and casein kinase II are located in the proximity of the actin-binding site. These results suggest, by analogy with what has been demonstrated in the case of other cytoskeletal proteins, that the phosphorylation of dystrophin by endogenous protein kinases may modulate both self assembly and interaction of dystrophin with other cytoskeletal proteins in vivo.
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4

Hurley, Rebecca L., Kristin A. Anderson, Jeanne M. Franzone, Bruce E. Kemp, Anthony R. Means, and Lee A. Witters. "The Ca2+/Calmodulin-dependent Protein Kinase Kinases Are AMP-activated Protein Kinase Kinases." Journal of Biological Chemistry 280, no. 32 (June 24, 2005): 29060–66. http://dx.doi.org/10.1074/jbc.m503824200.

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5

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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6

Jurcik, Jan, Barbara Sivakova, Ingrid Cipakova, Tomas Selicky, Erika Stupenova, Matus Jurcik, Michaela Osadska, Peter Barath, and Lubos Cipak. "Phosphoproteomics Meets Chemical Genetics: Approaches for Global Mapping and Deciphering the Phosphoproteome." International Journal of Molecular Sciences 21, no. 20 (October 15, 2020): 7637. http://dx.doi.org/10.3390/ijms21207637.

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Protein kinases are important enzymes involved in the regulation of various cellular processes. To function properly, each protein kinase phosphorylates only a limited number of proteins among the thousands present in the cell. This provides a rapid and dynamic regulatory mechanism that controls biological functions of the proteins. Despite the importance of protein kinases, most of their substrates remain unknown. Recently, the advances in the fields of protein engineering, chemical genetics, and mass spectrometry have boosted studies on identification of bona fide substrates of protein kinases. Among the various methods in protein kinase specific substrate identification, genetically engineered protein kinases and quantitative phosphoproteomics have become promising tools. Herein, we review the current advances in the field of chemical genetics in analog-sensitive protein kinase mutants and highlight selected strategies for identifying protein kinase substrates and studying the dynamic nature of protein phosphorylation.
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7

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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8

Yasuda, Jun, Alan J. Whitmarsh, Julie Cavanagh, Manoj Sharma, and Roger J. Davis. "The JIP Group of Mitogen-Activated Protein Kinase Scaffold Proteins." Molecular and Cellular Biology 19, no. 10 (October 1, 1999): 7245–54. http://dx.doi.org/10.1128/mcb.19.10.7245.

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ABSTRACT Activation of the c-Jun NH2-terminal kinase (JNK) group of mitogen-activated protein (MAP) kinases is mediated by a protein kinase cascade. This signaling mechanism may be coordinated by the interaction of components of the protein kinase cascade with scaffold proteins. The JNK-interacting protein (JIP) group of scaffold proteins selectively mediates signaling by the mixed-lineage kinase (MLK)→MAP kinase kinase 7 (MKK7)→JNK pathway. The scaffold proteins JIP1 and JIP2 interact to form oligomeric complexes that accumulate in peripheral cytoplasmic projections extended at the cell surface. The JIP proteins function by aggregating components of a MAP kinase module (including MLK, MKK7, and JNK) and facilitate signal transmission by the protein kinase cascade.
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9

Parker, P. J., and S. J. Parkinson. "AGC protein kinase phosphorylation and protein kinase C." Biochemical Society Transactions 29, no. 6 (November 1, 2001): 860–63. http://dx.doi.org/10.1042/bst0290860.

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Protein kinase cascades feature in many signal transduction pathways. For those discussed here, a single upstream protein kinase appears to be responsible for the control of multiple downstream targets. So how is specificity introduced into these events? For the downstream kinases (substrates) described here, it would appear that specificity is determined by substrate-directed events that are permissive for phosphorylation. There are also distinctions relating to the turnover of these phosphorylations providing a further element of specificity.
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10

Wille, Christoph, Thomas Seufferlein, and Tim Eiseler. "Protein Kinase D family kinases." BioArchitecture 4, no. 3 (March 12, 2014): 111–15. http://dx.doi.org/10.4161/bioa.29273.

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11

Wang, Pengcheng, Chuan-Chih Hsu, Yanyan Du, Peipei Zhu, Chunzhao Zhao, Xing Fu, Chunguang Zhang, et al. "Mapping proteome-wide targets of protein kinases in plant stress responses." Proceedings of the National Academy of Sciences 117, no. 6 (January 28, 2020): 3270–80. http://dx.doi.org/10.1073/pnas.1919901117.

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Protein kinases are major regulatory components in almost all cellular processes in eukaryotic cells. By adding phosphate groups, protein kinases regulate the activity, localization, protein–protein interactions, and other features of their target proteins. It is known that protein kinases are central components in plant responses to environmental stresses such as drought, high salinity, cold, and pathogen attack. However, only a few targets of these protein kinases have been identified. Moreover, how these protein kinases regulate downstream biological processes and mediate stress responses is still largely unknown. In this study, we introduce a strategy based on isotope-labeled in vitro phosphorylation reactions using in vivo phosphorylated peptides as substrate pools and apply this strategy to identify putative substrates of nine protein kinases that function in plant abiotic and biotic stress responses. As a result, we identified more than 5,000 putative target sites of osmotic stress-activated SnRK2.4 and SnRK2.6, abscisic acid-activated protein kinases SnRK2.6 and casein kinase 1-like 2 (CKL2), elicitor-activated protein kinase CDPK11 and MPK6, cold-activated protein kinase MPK6, H2O2-activated protein kinase OXI1 and MPK6, and salt-induced protein kinase SOS1 and MPK6, as well as the low-potassium-activated protein kinase CIPK23. These results provide comprehensive information on the role of these protein kinases in the control of cellular activities and could be a valuable resource for further studies on the mechanisms underlying plant responses to environmental stresses.
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12

Szyszka, R., A. Boguszewska, N. Grankowski, and J. P. Ballesta. "Differential phosphorylation of ribosomal acidic proteins from yeast cell by two endogenous protein kinases: casein kinase-2 and 60S kinase." Acta Biochimica Polonica 42, no. 3 (September 30, 1995): 357–62. http://dx.doi.org/10.18388/abp.1995_4634.

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The native 80S ribosomes isolated from Saccharomyces cerevisiae (strain W303) cells was phosphorylated by two endogenous protein kinases: multifunctional casein kinase-2 (CK-2) and specific 60S kinase. Three acidic proteins within the 60S ribosomal subunit: YP1 beta, YP1 beta' and YP2 alpha are phosphorylated by both kinases. The other two proteins: YP1 alpha and YP2 beta are predominantly phosphorylated by CK-2 but not by 60S kinase. This was confirmed in the experiment with the recombinant protein, YP2 beta, as a substrate, which is practically not phosphorylated by specific 60S kinase. These results together with the previous data based on the target amino-acid sequences suggest that, in addition to the multifunctional casein kinase-2 and specific 60S kinase, there exist probably other protein kinase(s) which phosphorylate the ribosomal acidic proteins in the cell.
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13

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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14

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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15

Smith, F. Donelson, Bret K. Samelson, and John D. Scott. "Discovery of cellular substrates for protein kinase A using a peptide array screening protocol." Biochemical Journal 438, no. 1 (July 27, 2011): 103–10. http://dx.doi.org/10.1042/bj20110720.

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Post-translational modification of proteins is a universal form of cellular regulation. Phosphorylation on serine, threonine, tyrosine or histidine residues by protein kinases is the most widespread and versatile form of covalent modification. Resultant changes in activity, localization or stability of phosphoproteins drives cellular events. MS and bioinformatic analyses estimate that ~30% of intracellular proteins are phosphorylated at any given time. Multiple approaches have been developed to systematically define targets of protein kinases; however, it is likely that we have yet to catalogue the full complement of the phosphoproteome. The amino acids that surround a phosphoacceptor site are substrate determinants for protein kinases. For example, basophilic enzymes such as PKA (protein kinase A), protein kinase C and calmodulin-dependent kinases recognize basic side chains preceding the target serine or threonine residues. In the present paper we describe a strategy using peptide arrays and motif-specific antibodies to identify and characterize previously unrecognized substrate sequences for protein kinase A. We found that the protein kinases PKD (protein kinase D) and MARK3 [MAP (microtubule-associated protein)-regulating kinase 3] can both be phosphorylated by PKA. Furthermore, we show that the adapter protein RIL [a product of PDLIM4 (PDZ and LIM domain protein 4)] is a PKA substrate that is phosphorylated on Ser119 inside cells and that this mode of regulation may control its ability to affect cell growth.
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16

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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17

Eto, Masumi, Shuichi Katsuki, Yoshinori Tanaka, and Kosuke Takeya. "Kinase activity-tagged western blotting assay." BioTechniques 68, no. 4 (April 2020): 211–13. http://dx.doi.org/10.2144/btn-2019-0136.

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Determining cellular activities of protein kinases is a fundamental step for characterizing pathophysiological cell signaling pathways. Here, we optimized a nonradioactive method that detects protein kinases in tissues or cells after separation by SDS-PAGE and transfer onto polyvinylidene fluoride membranes. The method, kinase activity-tagged western blotting (KAT-WB), consists of five steps: electrophoresis of cell extracts that contain protein kinases, electroblotting proteins onto polyvinylidene fluoride membrane, denaturation–renaturation, phosphorylation, with or without an added substrate protein and immunodetection using anti-phospho-specific antibodies. KAT-WB detected autophosphorylation of one Tyr-kinase and site-specific phosphorylation of added substrate by multiple kinases. KAT-WB assay enables us to interrogate multiple kinase signaling pathways without using radioactive ATP.
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18

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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19

Poon, Alice P. W., Luca Benetti, and Bernard Roizman. "US3 and US3.5 Protein Kinases of Herpes Simplex Virus 1 Differ with Respect to Their Functions in Blocking Apoptosis and in Virion Maturation and Egress." Journal of Virology 80, no. 8 (April 15, 2006): 3752–64. http://dx.doi.org/10.1128/jvi.80.8.3752-3764.2006.

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ABSTRACT Previously, we reported that the US3 protein kinase blocks apoptosis, that it activates protein kinase A (PKA), that activation of PKA blocks apoptosis in cells infected with a US3 deletion mutant, and that an overlapping transcriptional unit encodes a truncated kinase designated US3.5. Here, we report the properties of the kinases based on comparisons of herpes simplex virus and baculoviruses expressing US3 or US3.5 kinase. Specifically, we report the following. (i) Both kinases mediate the phosphorylation of HDAC1, HDAC2, and the PKA regulatory IIα subunit in the absence of other viral proteins. (ii) Both enzymes mediate the phosphorylation of largely identical sets of proteins carrying the phosphorylation consensus site of PKA, but only US3 blocks apoptosis, suggesting that it is US3 and not PKA that is responsible for the phosphorylation of the proteins bearing the shared consensus phosphorylation site and the antiapoptotic activity. (iii) Both kinases cofractionate with mitochondria. Immune depletion of the US3 and US3.5 kinases from the cytoplasm removed the kinases from the supernatant fraction, but not from the mitochondrial fraction, and therefore, if the antiapoptotic activity of the US3 kinase is expressed in mitochondria, the localization signal and the antiapoptotic functions are located on different parts of the protein. (iv) The US3 protein kinase is required for the translocation of virus particles from the nucleus. Although the UL31 protein is phosphorylated in cells infected with the mutant expressing US3.5 kinase, the release of virus particles from nuclei was impeded in some cells, suggesting that the US3 kinase affects the modification of the nuclear membrane more efficiently than the US3.5 kinase.
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20

Lee, K. S., K. Irie, Y. Gotoh, Y. Watanabe, H. Araki, E. Nishida, K. Matsumoto, and D. E. Levin. "A yeast mitogen-activated protein kinase homolog (Mpk1p) mediates signalling by protein kinase C." Molecular and Cellular Biology 13, no. 5 (May 1993): 3067–75. http://dx.doi.org/10.1128/mcb.13.5.3067-3075.1993.

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Mitogen-activated protein (MAP) kinases are activated in response to a variety of stimuli through a protein kinase cascade that results in their phosphorylation on tyrosine and threonine residues. The molecular nature of this cascade is just beginning to emerge. Here we report the isolation of a Saccharomyces cerevisiae gene encoding a functional analog of mammalian MAP kinases, designated MPK1 (for MAP kinase). The MPK1 gene was isolated as a dosage-dependent suppressor of the cell lysis defect associated with deletion of the BCK1 gene. The BCK1 gene is also predicted to encode a protein kinase which has been proposed to function downstream of the protein kinase C isozyme encoded by PKC1. The MPK1 gene possesses a 1.5-kb uninterrupted open reading frame predicted to encode a 53-kDa protein. The predicted Mpk1 protein (Mpk1p) shares 48 to 50% sequence identity with Xenopus MAP kinase and with the yeast mating pheromone response pathway components, Fus3p and Kss1p. Deletion of MPK1 resulted in a temperature-dependent cell lysis defect that was virtually indistinguishable from that resulting from deletion of BCK1, suggesting that the protein kinases encoded by these genes function in a common pathway. Expression of Xenopus MAP kinase suppressed the defect associated with loss of MPK1 but not the mating-related defects associated with loss of FUS3 or KSS1, indicating functional conservation between the former two protein kinases. Mutation of the presumptive phosphorylated tyrosine and threonine residues of Mpk1p individually to phenylalanine and alanine, respectively, severely impaired Mpk1p function. Additional epistasis experiments, and the overall architectural similarity between the PKC1-mediated pathway and the pheromone response pathway, suggest that Pkc1p regulates a protein kinase cascade in which Bck1p activates a pair of protein kinases, designated Mkk1p and Mkk2p (for MAP kinase-kinase), which in turn activate Mpk1p.
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Lee, K. S., K. Irie, Y. Gotoh, Y. Watanabe, H. Araki, E. Nishida, K. Matsumoto, and D. E. Levin. "A yeast mitogen-activated protein kinase homolog (Mpk1p) mediates signalling by protein kinase C." Molecular and Cellular Biology 13, no. 5 (May 1993): 3067–75. http://dx.doi.org/10.1128/mcb.13.5.3067.

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Mitogen-activated protein (MAP) kinases are activated in response to a variety of stimuli through a protein kinase cascade that results in their phosphorylation on tyrosine and threonine residues. The molecular nature of this cascade is just beginning to emerge. Here we report the isolation of a Saccharomyces cerevisiae gene encoding a functional analog of mammalian MAP kinases, designated MPK1 (for MAP kinase). The MPK1 gene was isolated as a dosage-dependent suppressor of the cell lysis defect associated with deletion of the BCK1 gene. The BCK1 gene is also predicted to encode a protein kinase which has been proposed to function downstream of the protein kinase C isozyme encoded by PKC1. The MPK1 gene possesses a 1.5-kb uninterrupted open reading frame predicted to encode a 53-kDa protein. The predicted Mpk1 protein (Mpk1p) shares 48 to 50% sequence identity with Xenopus MAP kinase and with the yeast mating pheromone response pathway components, Fus3p and Kss1p. Deletion of MPK1 resulted in a temperature-dependent cell lysis defect that was virtually indistinguishable from that resulting from deletion of BCK1, suggesting that the protein kinases encoded by these genes function in a common pathway. Expression of Xenopus MAP kinase suppressed the defect associated with loss of MPK1 but not the mating-related defects associated with loss of FUS3 or KSS1, indicating functional conservation between the former two protein kinases. Mutation of the presumptive phosphorylated tyrosine and threonine residues of Mpk1p individually to phenylalanine and alanine, respectively, severely impaired Mpk1p function. Additional epistasis experiments, and the overall architectural similarity between the PKC1-mediated pathway and the pheromone response pathway, suggest that Pkc1p regulates a protein kinase cascade in which Bck1p activates a pair of protein kinases, designated Mkk1p and Mkk2p (for MAP kinase-kinase), which in turn activate Mpk1p.
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22

Ahmed, Jefrin, Judith Mary Lamo, and Baphilinia Jones Mylliemngap. "Comparative Study of Active and Allosteric Interaction in Protein Kinases." Spectrum: Science and Technology 8, no. 1 (December 15, 2021): 23–31. http://dx.doi.org/10.54290/spect/2021.v8.1.0003.

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Protein kinases are key regulators of cell function that constitute one of the largest and most functionally diverse gene families. By adding phosphate groups to substrate proteins, they direct the activity, localization and overall function of many proteins, and serve to orchestrate the activity of almost all cellular processes. The main protein kinases consist of protein kinase A (PKA), protein kinase B (PKB), and protein kinase C (PKC) and are distinguished from each other by the different intracellular second messengers involved in their regulation and by the selective substrates they use. They all have a binding site for Mg2+-ATP (phosphate donor) and for substrate protein as well as various regulatory sites. We formulated to compare the binding capacity of protein kinases at the active site to allosteric sites. By comparing the active site and allosteric site of the protein kinases – A, B and C, using molecular docking it was found that in most of the cases the binding energy is high when an inhibitor binds to an active site as compared to the allosteric site. This comparison gave us an understanding of the interaction and inhibition of compounds to protein kinases in order to inhibit the activity of protein kinase A, B and C. It was concluded that for inhibiting the protein kinase function such as cell division and proliferation, binding of inhibitor to the allosteric site will be more effective.
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23

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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24

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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25

Hedbacker, Kristina, Seung-Pyo Hong, and Marian Carlson. "Pak1 Protein Kinase Regulates Activation and Nuclear Localization of Snf1-Gal83 Protein Kinase." Molecular and Cellular Biology 24, no. 18 (September 15, 2004): 8255–63. http://dx.doi.org/10.1128/mcb.24.18.8255-8263.2004.

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ABSTRACT Three kinases, Pak1, Tos3, and Elm1, activate Snf1 protein kinase in Saccharomyces cerevisiae. This cascade is conserved in mammals, where LKB1 activates AMP-activated protein kinase. We address the specificity of the activating kinases for the three forms of Snf1 protein kinase containing the β-subunit isoforms Gal83, Sip1, and Sip2. Pak1 is the most important kinase for activating Snf1-Gal83 in response to glucose limitation, but Elm1 also has a significant role; moreover, both Pak1 and Elm1 affect Snf1-Sip2. These findings exclude the possibility of a one-to-one correspondence between the activating kinases and the Snf1 complexes. We further identify a second, unexpected role for Pak1 in regulating Snf1-Gal83: the catalytic activity of Pak1 is required for the nuclear enrichment of Snf1-Gal83 in response to carbon stress. The nuclear enrichment of Snf1 fused to green fluorescent protein (GFP) depends on both Gal83 and Pak1 and is abolished by a mutation of the activation loop threonine; in contrast, the nuclear enrichment of Gal83-GFP occurs in a snf1Δ mutant and depends on Pak1 only when Snf1 is present. Snf1-Gal83 is the only form of the kinase that localizes to the nucleus. These findings, that Pak1 both activates Snf1-Gal83 and controls its nuclear localization, implicate Pak1 in regulating nuclear Snf1 protein kinase activity.
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26

Amano, Mutsuki, Tomonari Hamaguchi, Md Hasanuzzaman Shohag, Kei Kozawa, Katsuhiro Kato, Xinjian Zhang, Yoshimitsu Yura, et al. "Kinase-interacting substrate screening is a novel method to identify kinase substrates." Journal of Cell Biology 209, no. 6 (June 22, 2015): 895–912. http://dx.doi.org/10.1083/jcb.201412008.

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Protein kinases play pivotal roles in numerous cellular functions; however, the specific substrates of each protein kinase have not been fully elucidated. We have developed a novel method called kinase-interacting substrate screening (KISS). Using this method, 356 phosphorylation sites of 140 proteins were identified as candidate substrates for Rho-associated kinase (Rho-kinase/ROCK2), including known substrates. The KISS method was also applied to additional kinases, including PKA, MAPK1, CDK5, CaMK1, PAK7, PKN, LYN, and FYN, and a lot of candidate substrates and their phosphorylation sites were determined, most of which have not been reported previously. Among the candidate substrates for Rho-kinase, several functional clusters were identified, including the polarity-associated proteins, such as Scrib. We found that Scrib plays a crucial role in the regulation of subcellular contractility by assembling into a ternary complex with Rho-kinase and Shroom2 in a phosphorylation-dependent manner. We propose that the KISS method is a comprehensive and useful substrate screen for various kinases.
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27

Luttrell, Louis M. "Activation and targeting of mitogen-activated protein kinases by G-protein-coupled receptors." Canadian Journal of Physiology and Pharmacology 80, no. 5 (May 1, 2002): 375–82. http://dx.doi.org/10.1139/y02-045.

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Over the past decade, it has become apparent that many G-protein-coupled receptors (GPCRs) generate signals that control cellular differentiation and growth, including stimulation of Ras family GTPases and activation of mitogen-activated protein (MAP) kinase pathways. The mechanisms that GPCRs use to control the activity of MAP kinases vary between receptor and cell type but fall broadly into one of three categories: signals initiated by classical G protein effectors, e.g., protein kinase (PK)A and PKC, signals initiated by cross-talk between GPCRs and classical receptor tyrosine kinases, e.g., "transactivation" of epidermal growth factor (EGF) receptors, and signals initiated by direct interaction between β-arrestins and components of the MAP kinase cascade, e.g., β-arrestin "scaffolds". While each of these pathways results in increased cellular MAP kinase activity, emerging data suggest that they are not functionally redundant. MAP kinase activation occurring via PKC-dependent pathways and EGF receptor transactivation leads to nuclear translocation of the kinase and stimulates cell proliferation, while MAP kinase activation via β-arrestin scaffolds primarily increases cytosolic kinase activity. By controlling the spatial and temporal distribution of MAP kinase activity within the cell, the consequences of GPCR-stimulated MAP kinase activation may be determined by the mechanism by which they are activated.Key words: G-protein-coupled receptor, receptor tyrosine kinase, β-arrestin, mitogen-activated protein kinase, extracellular signal-regulated kinase.
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28

Póti, Ádám L., Laura Dénes, Kinga Papp, Csaba Bató, Zoltán Bánóczi, Attila Reményi, and Anita Alexa. "Phosphorylation-Assisted Luciferase Complementation Assay Designed to Monitor Kinase Activity and Kinase-Domain-Mediated Protein–Protein Binding." International Journal of Molecular Sciences 24, no. 19 (October 3, 2023): 14854. http://dx.doi.org/10.3390/ijms241914854.

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Protein kinases are key regulators of cell signaling and have been important therapeutic targets for three decades. ATP-competitive drugs directly inhibit the activity of kinases but these enzymes work as part of complex protein networks in which protein–protein interactions (often referred to as kinase docking) may govern a more complex activation pattern. Kinase docking is indispensable for many signaling disease-relevant Ser/Thr kinases and it is mediated by a dedicated surface groove on the kinase domain which is distinct from the substrate-binding pocket. Thus, interfering with kinase docking provides an alternative strategy to control kinases. We describe activity sensors developed for p90 ribosomal S6 kinase (RSK) and mitogen-activated protein kinases (MAPKs: ERK, p38, and JNK) whose substrate phosphorylation is known to depend on kinase-docking-groove-mediated protein–protein binding. The in vitro assays were based on fragment complementation of the NanoBit luciferase, which is facilitated upon substrate motif phosphorylation. The new phosphorylation-assisted luciferase complementation (PhALC) sensors are highly selective and the PhALC assay is a useful tool for the quantitative analysis of kinase activity or kinase docking, and even for high-throughput screening of academic compound collections.
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29

Tovell, Hannah, and Alexandra C. Newton. "Protein kinase C showcases allosteric control: activation of LRRK1." Biochemical Journal 480, no. 3 (February 10, 2023): 219–23. http://dx.doi.org/10.1042/bcj20220507.

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Allosteric regulation of multi-domain protein kinases provides a common mechanism to acutely control kinase activity. Protein kinase C serves as a paradigm for multi-domain proteins whose activity is exquisitely tuned by interdomain conformational changes that keep the enzyme off in the absence of appropriate stimuli, but unleash activity in response to second messenger binding. Allosteric regulation of protein kinase C signaling has been optimized not just for itself: Alessi and colleagues discover that protein kinase C phosphorylates LRRK1, a kinase with even more domains, at sites on its CORB GTPase domain to allosterically activate LRRK1.
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30

Qian, Xun, Jennifer Mitchell, Sung-Jen Wei, Jason Williams, Robert M. Petrovich, and Stephen B. Shears. "The Ins(1,3,4)P3 5/6-kinase/Ins(3,4,5,6)P4 1-kinase is not a protein kinase." Biochemical Journal 389, no. 2 (July 5, 2005): 389–95. http://dx.doi.org/10.1042/bj20050297.

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Among inositol phosphate kinases, Ins(3,4,5,6)P4 1-kinase has been considered to be an outsider with disparate sequence, a proclaimed capacity to also phosphorylate proteins and apparent 1-phosphatase activity. Such multifunctionality, coupled with ignorance of its operational domains, complicates any mechanistic rationale behind literature reports that Ins(3,4,5,6)P4 1-kinase regulates apoptosis, salt and fluid secretion, and transcription. We have expressed poly(His)-tagged human Ins(3,4,5,6)P4 1-kinase in Sf9 insect cells and purified the enzyme using Ni–agarose chromatography. Protein kinase activity was eluted from the Ni–agarose column, but this did not co-elute with the Ins(3,4,5,6)P4 1-kinase, indicating that the protein kinase and inositol kinase activities belong to separate proteins. To pursue this conclusion, we prepared catalytically inactive mutants of the Ins(3,4,5,6)P4 1-kinase by identifying and targeting the ATP-binding site. Our strategy was based on sequence alignments suggesting homology of the Ins(3,4,5,6)P4 1-kinase with ATP-grasp metabolic enzymes. Individual mutation of four candidate MgATP-binding participants, Lys157, Asp281, Asp295 and Asn297, severely compromised Ins(3,4,5,6)P4 1-kinase activity. Yet, these mutations did not affect the protein kinase activity. We conclude that the Ins(3,4,5,6)P4 1-kinase is not a protein kinase, contrary to earlier reports [e.g. Wilson, Sun, Cao and Majerus (2001) J. Biol. Chem. 276, 40998–41004]. Elimination of protein kinase activity from the enzyme's repertoire and recognition of its ATP-grasp homology together indicate that structural, functional and catalytic relationships between Ins(3,4,5,6)P4 1-kinase and other inositol phosphate kinases are closer than previously thought [Gonzalez, Schell, Letcher, Veprintsev, Irvine and Williams (2004) Mol. Cell 15, 689–701].
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31

Kelkar, Nyaya, Shashi Gupta, Martin Dickens, and Roger J. Davis. "Interaction of a Mitogen-Activated Protein Kinase Signaling Module with the Neuronal Protein JIP3." Molecular and Cellular Biology 20, no. 3 (February 1, 2000): 1030–43. http://dx.doi.org/10.1128/mcb.20.3.1030-1043.2000.

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ABSTRACT The c-Jun NH2-terminal kinase (JNK) group of mitogen-activated protein kinases (MAPKs) is activated in response to the treatment of cells with inflammatory cytokines and by exposure to environmental stress. JNK activation is mediated by a protein kinase cascade composed of a MAPK kinase and a MAPK kinase kinase. Here we describe the molecular cloning of a putative molecular scaffold protein, JIP3, that binds the protein kinase components of a JNK signaling module and facilitates JNK activation in cultured cells. JIP3 is expressed in the brain and at lower levels in the heart and other tissues. Immunofluorescence analysis demonstrated that JIP3 was present in the cytoplasm and accumulated in the growth cones of developing neurites. JIP3 is a member of a novel class of putative MAPK scaffold proteins that may regulate signal transduction by the JNK pathway.
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32

Foukas, L. C., and P. R. Shepherd. "Phosphoinositide 3-kinase: the protein kinase that time forgot." Biochemical Society Transactions 32, no. 2 (April 1, 2004): 330–31. http://dx.doi.org/10.1042/bst0320330.

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Class I phosphoinositide 3-kinases were originally characterized as lipid kinases, although more than 10 years ago they were also found to phosphorylate protein serine residues. However, while there is a vast amount of data on the function of this lipid kinase activity, relatively little is known about the function of the protein kinase activity. We discuss the evidence that suggests that the protein kinase activity of phosphoinositide 3-kinases mediates important signalling functions in cells.
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33

Johnson, L. "Protein kinases and their therapeutic exploitation." Biochemical Society Transactions 35, no. 1 (January 22, 2007): 7–11. http://dx.doi.org/10.1042/bst0350007.

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This review focuses on the recognition properties of protein kinases at the molecular level. Phosphorylation of the substrate protein by a protein kinase can result in enzyme activation or inhibition, conformational changes that change recognition properties, or the creation of a surface with distinct binding properties. Protein kinases have become important targets for the development of inhibitors with potential therapeutic application. Various examples are considered in this review, and I discuss our own work on glycogen phosphorylase and phosphorylase kinase, and the structures of proteins involved with the cell cycle, including cyclins and cyclin-dependent kinases.
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34

Díaz-Nido, J., L. Serrano, E. Méndez, and J. Avila. "A casein kinase II-related activity is involved in phosphorylation of microtubule-associated protein MAP-1B during neuroblastoma cell differentiation." Journal of Cell Biology 106, no. 6 (June 1, 1988): 2057–65. http://dx.doi.org/10.1083/jcb.106.6.2057.

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A neuroblastoma protein related to the brain microtubule-associated protein, MAP-1B, as determined by immunoprecipitation and coassembly with brain microtubules, becomes phosphorylated when N2A mouse neuroblastoma cells are induced to generate microtubule-containing neurites. To characterize the protein kinases that may be involved in this in vivo phosphorylation of MAP-1B, we have studied its in vitro phosphorylation. In brain microtubule protein, MAP-1B appears to be phosphorylated in vitro by an endogenous casein kinase II-like activity which also phosphorylates the related protein MAP-1A but scarcely phosphorylates MAP-2. A similar kinase activity has been detected in cell-free extracts of differentiating N2A cells. Using brain MAP preparations devoid of endogenous kinase activities and different purified protein kinases, we have found that MAP-1B is barely phosphorylated by cAMP-dependent protein kinase, Ca/calmodulin-dependent protein kinase, or Ca/phospholipid-dependent protein kinase whereas MAP-1B is one of the preferred substrates, together with MAP-1A, for casein kinase II. Brain MAP-1B phosphorylated in vitro by casein kinase II efficiently coassembles with microtubule proteins in the same way as in vivo phosphorylated MAP-1B from neuroblastoma cells. Furthermore, the phosphopeptide patterns of brain MAP-1B phosphorylated in vitro by either purified casein kinase II or an extract obtained from differentiating neuroblastoma cells are identical to each other and similar to that of in vivo phosphorylated neuroblastoma MAP-1B. Thus, we suggest that the observed phosphorylation of a protein identified as MAP-1B during neurite outgrowth is mainly due to the activation of a casein kinase II-related activity in differentiating neuroblastoma cells. This kinase activity, previously implicated in beta-tubulin phosphorylation (Serrano, L., J. Díaz-Nido, F. Wandosell, and J. Avila, 1987. J. Cell Biol. 105: 1731-1739), may consequently have an important role in posttranslational modifications of microtubule proteins required for neuronal differentiation.
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35

Moens, Ugo, and Sergiy Kostenko. "Structure and function of MK5/PRAK: the loner among the mitogen-activated protein kinase-activated protein kinases." Biological Chemistry 394, no. 9 (September 1, 2013): 1115–32. http://dx.doi.org/10.1515/hsz-2013-0149.

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Abstract Mitogen-activated protein kinase (MAPK) pathways are important signal transduction pathways that control pivotal cellular processes including proliferation, differentiation, survival, apoptosis, gene regulation, and motility. MAPK pathways consist of a relay of consecutive phosphorylation events exerted by MAPK kinase kinases, MAPK kinases, and MAPKs. Conventional MAPKs are characterized by a conserved Thr-X-Tyr motif in the activation loop of the kinase domain, while atypical MAPKs lack this motif and do not seem to be organized into the classical three-tiered kinase cascade. One functional group of conventional and atypical MAPK substrates consists of protein kinases known as MAPK-activated protein kinases. Eleven mammalian MAPK-activated protein kinases have been identified, and they are divided into five subgroups: the ribosomal-S6-kinases RSK1-4, the MAPK-interacting kinases MNK1 and 2, the mitogen- and stress-activated kinases MSK1 and 2, the MAPK-activated protein kinases MK2 and 3, and the MAPK-activated protein kinase MK5 (also referred to as PRAK). MK5/PRAK is the only MAPK-activated protein kinase that is a substrate for both conventional and atypical MAPK, while all other MAPKAPKs are exclusively phosphorylated by conventional MAPKs. This review focuses on the structure, activation, substrates, functions, and possible implications of MK5/PRAK in malignant and nonmalignant diseases.
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36

Kelkar, Nyaya, Claire L. Standen, and Roger J. Davis. "Role of the JIP4 Scaffold Protein in the Regulation of Mitogen-Activated Protein Kinase Signaling Pathways." Molecular and Cellular Biology 25, no. 7 (April 1, 2005): 2733–43. http://dx.doi.org/10.1128/mcb.25.7.2733-2743.2005.

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ABSTRACT The c-Jun NH2-terminal kinase (JNK)-interacting protein (JIP) group of scaffold proteins (JIP1, JIP2, and JIP3) can interact with components of the JNK signaling pathway and potently activate JNK. Here we describe the identification of a fourth member of the JIP family. The primary sequence of JIP4 is most closely related to that of JIP3. Like other members of the JIP family of scaffold proteins, JIP4 binds JNK and also the light chain of the microtubule motor protein kinesin-1. However, the function of JIP4 appears to be markedly different from other JIP proteins. Specifically, JIP4 does not activate JNK signaling. In contrast, JIP4 serves as an activator of the p38 mitogen-activated protein (MAP) kinase pathway by a mechanism that requires the MAP kinase kinases MKK3 and MKK6. The JIP4 scaffold protein therefore appears to be a new component of the p38 MAP kinase signaling pathway.
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37

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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38

Kracht, M., O. Truong, N. F. Totty, M. Shiroo, and J. Saklatvala. "Interleukin 1 alpha activates two forms of p54 alpha mitogen-activated protein kinase in rabbit liver." Journal of Experimental Medicine 180, no. 6 (December 1, 1994): 2017–25. http://dx.doi.org/10.1084/jem.180.6.2017.

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We have identified in rabbits two hepatic forms of T669 peptide kinases that are very strongly activated after systemic injection with the inflammatory cytokine interleukin 1 (IL-1). The T669 peptide contains a major phosphorylation site of the epidermal growth factor receptor, threonine 699 and is a substrate for mitogen-activated protein (MAP) kinases. The kinases were purified to homogeneity and corresponded to 50- and 55-kD proteins on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Amino acid sequencing of 12 tryptic peptides of both kinases identified them as p54 MAP kinase alpha. This kinase belongs to the novel family of stress-activated protein kinases. This is the first evidence of IL-1 activating a specific protein kinase in vivo.
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39

Nguyen, Kim B., Anju Sreelatha, Eric S. Durrant, Javier Lopez-Garrido, Anna Muszewska, Małgorzata Dudkiewicz, Marcin Grynberg, et al. "Phosphorylation of spore coat proteins by a family of atypical protein kinases." Proceedings of the National Academy of Sciences 113, no. 25 (May 16, 2016): E3482—E3491. http://dx.doi.org/10.1073/pnas.1605917113.

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The modification of proteins by phosphorylation occurs in all life forms and is catalyzed by a large superfamily of enzymes known as protein kinases. We recently discovered a family of secretory pathway kinases that phosphorylate extracellular proteins. One member, family with sequence similarity 20C (Fam20C), is the physiological Golgi casein kinase. While examining distantly related protein sequences, we observed low levels of identity between the spore coat protein H (CotH), and the Fam20C-related secretory pathway kinases. CotH is a component of the spore in many bacterial and eukaryotic species, and is required for efficient germination of spores inBacillus subtilis; however, the mechanism by which CotH affects germination is unclear. Here, we show that CotH is a protein kinase. The crystal structure of CotH reveals an atypical protein kinase-like fold with a unique mode of ATP binding. Examination of the genes neighboringcotHinB. subtilisled us to identify two spore coat proteins, CotB and CotG, as CotH substrates. Furthermore, we show that CotH-dependent phosphorylation of CotB and CotG is required for the efficient germination ofB. subtilisspores. Collectively, our results define a family of atypical protein kinases and reveal an unexpected role for protein phosphorylation in spore biology.
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40

TOOMIK, Reet, and Pia EK. "A potent and highly selective peptide substrate for protein kinase C assay." Biochemical Journal 322, no. 2 (March 1, 1997): 455–60. http://dx.doi.org/10.1042/bj3220455.

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Protein kinases exhibit substrate specificities that are often primarily determined by the amino acids around the phosphorylation sites. Peptides corresponding to protein kinase C phosphorylation sites in several different proteins were synthesized on SPOTs membrane which has recently been found to be applicable for studies of protein kinase specificity. After phosphorylation with protein kinase C, we chose the best phosphorylated peptides for the investigation of the importance of amino acids immediately adjacent to the phosphorylation site. The selectivity of the best protein kinase C substrates from this study was analysed with protein kinases A, CK1 and CK2. According to these tests, the most favourable characteristics of SPOTs-membrane-associated peptides were demonstrated by peptide KRAKRKTAKKR. Kinetic analysis of peptide phosphorylation with protein kinase C revealed an apparent Km of 0.49±0.13 μM and Vmax of 10.0±0.5 nmol/min per mg with soluble peptide KRAKRKTAKKR. In addition, we assayed several other soluble peptides commonly used as protein kinase C substrates. Peptide KRAKRKTAKKR showed the lowest Km and the highest Vmax/Km value in comparison with peptides FKKSFKL, pEKRPSQRSKYL and KRAKRKTTKKR. Furthermore, of the peptides tested, KRAKRKTAKKR was the most selective substrate for protein kinase C. The favourable kinetic parameters combined with the selectivity should make the KRAKRKTAKKR peptide useful as a substrate for protein kinase C in the assays of both purified enzyme and in crude cell extracts.
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41

Obsilova, Veronika, and Tomas Obsil. "The 14-3-3 Proteins as Important Allosteric Regulators of Protein Kinases." International Journal of Molecular Sciences 21, no. 22 (November 21, 2020): 8824. http://dx.doi.org/10.3390/ijms21228824.

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Phosphorylation by kinases governs many key cellular and extracellular processes, such as transcription, cell cycle progression, differentiation, secretion and apoptosis. Unsurprisingly, tight and precise kinase regulation is a prerequisite for normal cell functioning, whereas kinase dysregulation often leads to disease. Moreover, the functions of many kinases are regulated through protein–protein interactions, which in turn are mediated by phosphorylated motifs and often involve associations with the scaffolding and chaperon protein 14-3-3. Therefore, the aim of this review article is to provide an overview of the state of the art on 14-3-3-mediated kinase regulation, focusing on the most recent mechanistic insights into these important protein–protein interactions and discussing in detail both their structural aspects and functional consequences.
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42

Wu, J., H. Michel, A. Rossomando, T. Haystead, J. Shabanowitz, D. F. Hunt, and T. W. Sturgill. "Renaturation and partial peptide sequencing of mitogen-activated protein kinase (MAP kinase) activator from rabbit skeletal muscle." Biochemical Journal 285, no. 3 (August 1, 1992): 701–5. http://dx.doi.org/10.1042/bj2850701.

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Mitogen-activated protein kinase (MAP kinase) activator was purified 2000-fold from skeletal muscle, and proteins which co-purified with the activator were analysed after SDS/PAGE by renaturation and partial sequencing. Activity for tyrosine and threonine phosphorylation of MAP kinase was present in two bands of approx. 48 and 46 kDa, which have sequence similarity to small GTP-binding protein p25 GDP dissociation inhibitor and protein kinases (PBS2, SPK1+, STE7, BYR1) respectively.
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43

Torrecilla, Ignacio, Elizabeth J. Spragg, Benoit Poulin, Phillip J. McWilliams, Sharad C. Mistry, Andree Blaukat, and Andrew B. Tobin. "Phosphorylation and regulation of a G protein–coupled receptor by protein kinase CK2." Journal of Cell Biology 177, no. 1 (April 2, 2007): 127–37. http://dx.doi.org/10.1083/jcb.200610018.

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We demonstrate a role for protein kinase casein kinase 2 (CK2) in the phosphorylation and regulation of the M3-muscarinic receptor in transfected cells and cerebellar granule neurons. On agonist occupation, specific subsets of receptor phosphoacceptor sites (which include the SASSDEED motif in the third intracellular loop) are phosphorylated by CK2. Receptor phosphorylation mediated by CK2 specifically regulates receptor coupling to the Jun-kinase pathway. Importantly, other phosphorylation-dependent receptor processes are regulated by kinases distinct from CK2. We conclude that G protein–coupled receptors (GPCRs) can be phosphorylated in an agonist-dependent fashion by protein kinases from a diverse range of kinase families, not just the GPCR kinases, and that receptor phosphorylation by a defined kinase determines a specific signalling outcome. Furthermore, we demonstrate that the M3-muscarinic receptor can be differentially phosphorylated in different cell types, indicating that phosphorylation is a flexible regulatory process where the sites that are phosphorylated, and hence the signalling outcome, are dependent on the cell type in which the receptor is expressed.
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44

Chung, J., R. H. Chen, and J. Blenis. "Coordinate regulation of pp90rsk and a distinct protein-serine/threonine kinase activity that phosphorylates recombinant pp90rsk in vitro." Molecular and Cellular Biology 11, no. 4 (April 1991): 1868–74. http://dx.doi.org/10.1128/mcb.11.4.1868-1874.1991.

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Protein kinase assays that use recombinant pp90rsk as a substrate were developed in an attempt to identify growth-regulated enzymes responsible for the phosphorylation and activation of pp90rsk S6 phosphotransferase activity. With this assay we have ientified a pp60v-src-, growth factor-, phorbol ester-, and vanadate-regulated serine/threonine protein kinase activity that is not related to two other cofactor-independent, growth-regulated protein kinases, pp70-S6 protein kinase and pp90rsk. The pp90rsk-protein kinase activity (referred to as rsk-kinase) is also not related to cofactor-dependent signal transducing protein kinases such as the cyclic AMP-dependent protein kinases, members of the protein kinase C family, or other Ca2(+)-dependent protein kinases. In vitro, partially purified rsk-kinase phosphorylates several of the sites (serine and threonine) that are phosphorylated in growth-stimulated cultured cells. A detailed examination of the mitogen-regulated activation kinetics of rsk-kinase and pp90rsk activities demonstrated that they are coordinately regulated. In addition, protein kinase C is not absolutely required for epidermal and fibroblast growth factor-stimulated activation of rsk-kinase, whereas, like pp90rsk, platelet-derived growth factor- and vanadate-stimulated rsk-kinase activity exhibits a greater dependence on protein kinase C-mediated signal transduction. The characterization and future purification of the rsk-kinase(s) will improve our understanding of the early signaling events regulating cell growth.
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45

Chung, J., R. H. Chen, and J. Blenis. "Coordinate regulation of pp90rsk and a distinct protein-serine/threonine kinase activity that phosphorylates recombinant pp90rsk in vitro." Molecular and Cellular Biology 11, no. 4 (April 1991): 1868–74. http://dx.doi.org/10.1128/mcb.11.4.1868.

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Abstract:
Protein kinase assays that use recombinant pp90rsk as a substrate were developed in an attempt to identify growth-regulated enzymes responsible for the phosphorylation and activation of pp90rsk S6 phosphotransferase activity. With this assay we have ientified a pp60v-src-, growth factor-, phorbol ester-, and vanadate-regulated serine/threonine protein kinase activity that is not related to two other cofactor-independent, growth-regulated protein kinases, pp70-S6 protein kinase and pp90rsk. The pp90rsk-protein kinase activity (referred to as rsk-kinase) is also not related to cofactor-dependent signal transducing protein kinases such as the cyclic AMP-dependent protein kinases, members of the protein kinase C family, or other Ca2(+)-dependent protein kinases. In vitro, partially purified rsk-kinase phosphorylates several of the sites (serine and threonine) that are phosphorylated in growth-stimulated cultured cells. A detailed examination of the mitogen-regulated activation kinetics of rsk-kinase and pp90rsk activities demonstrated that they are coordinately regulated. In addition, protein kinase C is not absolutely required for epidermal and fibroblast growth factor-stimulated activation of rsk-kinase, whereas, like pp90rsk, platelet-derived growth factor- and vanadate-stimulated rsk-kinase activity exhibits a greater dependence on protein kinase C-mediated signal transduction. The characterization and future purification of the rsk-kinase(s) will improve our understanding of the early signaling events regulating cell growth.
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46

Treharne, K. J., L. J. Marshall, and A. Mehta. "A novel chloride-dependent GTP-utilizing protein kinase in plasma membranes from human respiratory epithelium." American Journal of Physiology-Lung Cellular and Molecular Physiology 267, no. 5 (November 1, 1994): L592—L601. http://dx.doi.org/10.1152/ajplung.1994.267.5.l592.

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The protein kinases that stimulate ion flux across airway epithelium are believed to utilize ATP as phosphate donor. Here we show that a chloride-sensitive protein kinase (in an apically enriched plasma membrane fraction from human nasal respiratory epithelium) uses guanosine 5'-triphosphate in preference to ATP as phosphate donor and is not inhibited by the protein kinase inhibitors staurosporine, 1-(5-isoquinolinylsulfonyl)-2-methylpiperazine, and N-(2-guanodinoethyl)-5-isoquinoline sulfonamide. This kinase phosphorylates a 37-kDa membrane protein (p37), which exhibits a 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid (DIDS)-sensitive phosphorylation peak at 40 mM Cl- (DIDS inhibition constant = 8 microM). p37 is additionally phosphorylated by an N-(2-guanodinoethyl)-5-isoquinoline sulfonamide-inhibitable protein kinase that uses ATP and shows a similar chloride sensitivity. The profile of membrane phosphoproteins generated by both kinases is also dependent on the source of Pi, the species of anion, and the concentration of anion. We propose a molecular mechanism for the transduction of Cl- concentration into a guanosine 5'-triphosphate-selective protein kinase signal and show that anion substitution alters the intensity of phosphorylation of membrane proteins in the absence of exogenously added protein kinases.
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47

VerPlank, Jordan J. S., and Alfred L. Goldberg. "Regulating protein breakdown through proteasome phosphorylation." Biochemical Journal 474, no. 19 (September 25, 2017): 3355–71. http://dx.doi.org/10.1042/bcj20160809.

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The ubiquitin proteasome system degrades the great majority of proteins in mammalian cells. Countless studies have described how ubiquitination promotes the selective degradation of different cell proteins. However, there is a small but growing literature that protein half-lives can also be regulated by post-translational modifications of the 26S proteasome. The present study reviews the ability of several kinases to alter proteasome function through subunit phosphorylation. For example, PKA (protein kinase A) and DYRK2 (dual-specificity tyrosine-regulated kinase 2) stimulate the proteasome's ability to degrade ubiquitinated proteins, peptides, and adenosine triphosphate, while one kinase, ASK1 (apoptosis signal-regulating kinase 1), inhibits proteasome function during apoptosis. Proteasome phosphorylation is likely to be important in regulating protein degradation because it occurs downstream from many hormones and neurotransmitters, in conditions that raise cyclic adenosine monophosphate or cyclic guanosine monophosphate levels, after calcium influx following synaptic depolarization, and during phases of the cell cycle. Beyond its physiological importance, pharmacological manipulation of proteasome phosphorylation has the potential to combat various diseases. Inhibitors of phosphodiesterases by activating PKA or PKG (protein kinase G) can stimulate proteasomal degradation of misfolded proteins that cause neurodegenerative or myocardial diseases and even reduce the associated pathology in mouse models. These observations are promising since in many proteotoxic diseases, aggregation-prone proteins impair proteasome function, and disrupt protein homeostasis. Conversely, preventing subunit phosphorylation by DYRK2 slows cell cycle progression and tumor growth. However, further research is essential to determine how phosphorylation of different subunits by these (or other) kinases alters the properties of this complex molecular machine and thus influence protein degradation rates.
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48

Bharucha, Nikë, Jun Ma, Craig J. Dobry, Sarah K. Lawson, Zhifen Yang, and Anuj Kumar. "Analysis of the Yeast Kinome Reveals a Network of Regulated Protein Localization during Filamentous Growth." Molecular Biology of the Cell 19, no. 7 (July 2008): 2708–17. http://dx.doi.org/10.1091/mbc.e07-11-1199.

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The subcellular distribution of kinases and other signaling proteins is regulated in response to cellular cues; however, the extent of this regulation has not been investigated for any gene set in any organism. Here, we present a systematic analysis of protein kinases in the budding yeast, screening for differential localization during filamentous growth. Filamentous growth is an important stress response involving mitogen-activated protein kinase and cAMP-dependent protein kinase signaling modules, wherein yeast cells form interconnected and elongated chains. Because standard strains of yeast are nonfilamentous, we constructed a unique set of 125 kinase-yellow fluorescent protein chimeras in the filamentous Σ1278b strain for this study. In total, we identified six cytoplasmic kinases (Bcy1p, Fus3p, Ksp1p, Kss1p, Sks1p, and Tpk2p) that localize predominantly to the nucleus during filamentous growth. These kinases form part of an interdependent, localization-based regulatory network: deletion of each individual kinase, or loss of kinase activity, disrupts the nuclear translocation of at least two other kinases. In particular, this study highlights a previously unknown function for the kinase Ksp1p, indicating the essentiality of its nuclear translocation during yeast filamentous growth. Thus, the localization of Ksp1p and the other kinases identified here is tightly controlled during filamentous growth, representing an overlooked regulatory component of this stress response.
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49

Mitra, Sutapa, Debjani Nath, and Gopal C. Majumder. "Purification and characterization of a protein kinase from goat sperm plasma membrane." Biochemistry and Cell Biology 72, no. 5-6 (May 1, 1994): 218–26. http://dx.doi.org/10.1139/o94-031.

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A protein kinase that causes phosphorylation of serine and threonine residues of casein has been partially purified from goat cauda-epididymal sperm plasma membrane and characterized. The kinase, solubilized from the membrane with 1.0% Triton X-100, was purified to 480-fold by using DEAE-cellulose and casein-Sepharose affinity chromatographic techniques. The kinase is a strongly basic protein with pI of 9.5. The enzyme has a molecular mass of 310 kilodaltons as estimated by Sephacryl S-300 gel exclusion. The kinase showed affinity for protein substrates in the order membrane proteins > casein > phosvitin > histone > protamine. The apparent Km values of the kinase for casein and membrane proteins were 1 and 0.15 mg/mL, respectively. The synthetic peptides Kemptide and poly(Glu80Tyr20) did not serve as substrates of the enzyme. ATP, rather than GTP or PP, is the donor of phosphate for the phosphorylation reaction. Cyclic AMP and GMP, NaCl (0.25 M), KCl (0.25 M), Ca2+, calmodulin, phosphatidylserine, and muscle protein kinase inhibitor had no appreciable effect on the kinase activity. Heparin (0.5 μg/mL) showed high affinity for inhibiting only 40% of the kinase activity, whereas polyamines at a relatively high concentration (5 mM) inhibited 40–50% of the enzymic activity. The kinase appears to be distinct from other protein kinases including casein kinases. The activity of the kinase derived from the purified sperm plasma membrane was markedly (~ 90%) lost when the intact spermatozoa were pretreated with diazonium salt of sulfanilic acid, a membrane nonpenetrating surface probe. The data are consistent with the view that the isolated enzyme is an ecto-protein kinase whose catalytic site is oriented primarily to the surface of viable sperm cell to cause phosphorylation of the endogenous outer cell-surface phosphoproteins.Key words: spermatozoa, plasma membrane, protein kinase, phosphoproteins, ectoenzyme.
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50

Wang, Qin, Michael Yerukhimovich, William A. Gaarde, Ian J. Popoff, and Claire M. Doerschuk. "MKK3 and -6-dependent activation of p38α MAP kinase is required for cytoskeletal changes in pulmonary microvascular endothelial cells induced by ICAM-1 ligation." American Journal of Physiology-Lung Cellular and Molecular Physiology 288, no. 2 (February 2005): L359—L369. http://dx.doi.org/10.1152/ajplung.00292.2004.

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Previous studies demonstrated that neutrophil adherence induces ICAM-1-dependent cytoskeletal changes in TNF-α-treated pulmonary microvascular endothelial cells that are prevented by a pharmacological inhibitor of p38 MAP kinase. This study determined whether neutrophil adherence induces activation of p38 MAP kinase in endothelial cells, the subcellular localization of phosphorylated p38, which MAP kinase kinases lead to p38 activation, which p38 isoform is activated, and what the downstream targets may be. Confocal microscopy showed that neutrophil adhesion for 2 or 6 min induced an increase in phosphorylated p38 in endothelial cells that was punctate and concentrated in the central region of the endothelial cells. Studies using small interfering RNA (siRNA) to inhibit the protein expression of MAP kinase kinase 3 and 6, either singly or in combination, showed that both MAP kinase kinases were required for p38 phosphorylation. Studies using an antisense oligonucleotide to p38α demonstrated that inhibition of the protein expression of p38α 1) inhibited activation of p38 MAP kinase without affecting the protein expression of p38β; 2) prevented phosphorylation of heat shock protein 27, an actin binding protein that may induce actin polymerization upon phosphorylation; 3) attenuated cytoskeletal changes; and 4) attenuated neutrophil migration to the EC borders. Thus MAP kinase kinase3- and 6-dependent activation of the α-isoform of p38 MAP kinase is required for the cytoskeletal changes induced by neutrophil adherence and influences subsequent neutrophil migration toward endothelial cell junctions.
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