The Experts below are selected from a list of 142317 Experts worldwide ranked by ideXlab platform
J Avruch - One of the best experts on this subject based on the ideXlab platform.
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an array of insulin activated proline directed serine threonine Protein Kinases phosphorylate the p70 s6 kinase
Journal of Biological Chemistry, 1992Co-Authors: N K Mukhopadhyay, D J Price, J M Kyriakis, S Pelech, J Sanghera, J AvruchAbstract:Abstract This study characterizes the insulin-activated serine/threonine Protein Kinases in H4 hepatoma cells active on a 37-residue synthetic peptide (called the SKAIPS peptide) corresponding to a putative autoinhibitory domain in the carboxyl-terminal tail of the p70 S6 kinase as well as on recombinant p70 S6 kinase. Three peaks of insulin-stimulated Protein kinase active on both these substrates are identified as two (possibly three) isoforms of the 40-45-kDa erk/microtubule-associated Protein (MAP)-2 kinase family and a 150-kDa form of cdc2. Although distinguishable in their substrate specificity, these Protein Kinases together with the p54 MAP-2 kinase share a major common specificity determinant reflected in the SKAIPS peptide: the requirement for a proline residue immediately carboxyl-terminal to the site of Ser/Thr phosphorylation. In addition, however, at least one peak of insulin-stimulated Protein kinase active on recombinant p70, but not on the SKAIPS peptide, is present although not yet identified. MFP/cdc2 phosphorylates both rat liver p70 S6 kinase and recombinant p70 S6 kinase exclusively at a set of Ser/Thr residues within the putative autoinhibitory (SKAIPS peptide) domain. erk/MAP kinase does not phosphorylate rat liver p70 S6 kinase, but readily phosphorylates recombinant p70 S6 kinase at sites both within and in addition to those encompassed by the SKAIPS peptide sequences. Although the tryptic 32P-peptides bearing the cdc2 and erk/MAP kinase phosphorylation sites co-migrate with a subset of the sites phosphorylated in situ in insulin-stimulated cells, phosphorylation of the p70 S6 kinase by these proline-directed Protein Kinases in vitro does not reproducibly activate p70 S6 kinase activity. Thus, one or more erk/MAP Kinases and cdc2 are likely to participate in the insulin-induced phosphorylation of the p70 S6 kinase. In addition to these Kinases, however, phosphorylation of the p70 S6 kinase by other as yet unidentified Protein Kinases is necessary to recapitulate the multisite phosphorylation required for activation of the p70 S6 kinase.
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Insulin-activated Protein Kinases phosphorylate a pseudosubstrate synthetic peptide inhibitor of the p70 S6 kinase.
The Journal of biological chemistry, 1991Co-Authors: D J Price, N K Mukhopadhyay, J AvruchAbstract:p70 S6 kinase, a major insulin-mitogen-activated ribosomal S6 Protein kinase in mammalian cells, is activated by phosphorylation of multiple Ser/Thr residues on the enzyme polypeptide. A synthetic peptide, corresponding to a 37-residue segment from the carboxyl-terminal tail of the kinase which resembles the sequence phosphorylated in S6, acts as a competitive inhibitor of p70 S6 kinase without itself being phosphorylated by the enzyme. This synthetic peptide is phosphorylated by an array of Protein Kinases which are rapidly activated by insulin. Thus, these sequences of p70 S6 kinase constitute a potential autoinhibitory pseudosubstrate site, whose phosphorylation is catalyzed by candidate upstream-activating Protein Kinases.
John D Scott - One of the best experts on this subject based on the ideXlab platform.
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cyclic nucleotide dependent Protein Kinases
Pharmacology & Therapeutics, 1991Co-Authors: John D ScottAbstract:The actions of several hormones and neurotransmitters evoke signal transduction pathways which rapidly elevate the cytosolic concentrations of the intracellular messengers, cAMP and cGMP. The cyclic-nucleotide dependent Protein Kinases, cAMP-dependent Protein kinase (PKA) and cGMP-dependent Protein kinase (PKG), are the major intracellular receptors of cAMP and cGMP. These enzymes become active upon binding respective cyclic nucleotides and modulate a diverse array of biochemical events through the phosphorylation of specific substrate Proteins. The focus of this review is to describe the progress made in understanding the structure and function of both PKA and PKG.
Tina Romeis - One of the best experts on this subject based on the ideXlab platform.
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calcium dependent Protein Kinases hubs in plant stress signaling and development
Plant Physiology, 2013Co-Authors: Philipp Schulz, Marco Herde, Tina RomeisAbstract:Calcium ions (Ca2+) have long been recognized as a major, conserved second messenger in eukaryotic signal transduction. In plants, the multigene family of calcium-dependent Protein Kinases (CDPKs) encodes structurally conserved, unimolecular calcium sensor/Protein kinase effector Proteins. CDPKs are
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Protein Kinases in the plant defence response
Current Opinion in Plant Biology, 2001Co-Authors: Tina RomeisAbstract:Protein Kinases play a central role in signalling during pathogen recognition and the subsequent activation of plant defence mechanisms. Members of different kinase subfamilies, such as calcium-dependent Protein Kinases and MAP Kinases, are involved. Nevertheless, often, only a single component of a signalling cascade in an experimental plant system has been characterised. The future challenge is to understand how these Kinases work, which cellular responses they mediate, and how they fit into the bigger picture of defence signalling. This challenge has become increasingly feasible with the recent introduction of new techniques: these techniques include reverse genetics, which will allow the allocation of biological function to kinase isoforms, (phospho) proteomics combined with mass spectrometry, and transient expression of Kinases in a (constitutively) active form, mimicking the induction of defence responses in a biological system.
N K Mukhopadhyay - One of the best experts on this subject based on the ideXlab platform.
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an array of insulin activated proline directed serine threonine Protein Kinases phosphorylate the p70 s6 kinase
Journal of Biological Chemistry, 1992Co-Authors: N K Mukhopadhyay, D J Price, J M Kyriakis, S Pelech, J Sanghera, J AvruchAbstract:Abstract This study characterizes the insulin-activated serine/threonine Protein Kinases in H4 hepatoma cells active on a 37-residue synthetic peptide (called the SKAIPS peptide) corresponding to a putative autoinhibitory domain in the carboxyl-terminal tail of the p70 S6 kinase as well as on recombinant p70 S6 kinase. Three peaks of insulin-stimulated Protein kinase active on both these substrates are identified as two (possibly three) isoforms of the 40-45-kDa erk/microtubule-associated Protein (MAP)-2 kinase family and a 150-kDa form of cdc2. Although distinguishable in their substrate specificity, these Protein Kinases together with the p54 MAP-2 kinase share a major common specificity determinant reflected in the SKAIPS peptide: the requirement for a proline residue immediately carboxyl-terminal to the site of Ser/Thr phosphorylation. In addition, however, at least one peak of insulin-stimulated Protein kinase active on recombinant p70, but not on the SKAIPS peptide, is present although not yet identified. MFP/cdc2 phosphorylates both rat liver p70 S6 kinase and recombinant p70 S6 kinase exclusively at a set of Ser/Thr residues within the putative autoinhibitory (SKAIPS peptide) domain. erk/MAP kinase does not phosphorylate rat liver p70 S6 kinase, but readily phosphorylates recombinant p70 S6 kinase at sites both within and in addition to those encompassed by the SKAIPS peptide sequences. Although the tryptic 32P-peptides bearing the cdc2 and erk/MAP kinase phosphorylation sites co-migrate with a subset of the sites phosphorylated in situ in insulin-stimulated cells, phosphorylation of the p70 S6 kinase by these proline-directed Protein Kinases in vitro does not reproducibly activate p70 S6 kinase activity. Thus, one or more erk/MAP Kinases and cdc2 are likely to participate in the insulin-induced phosphorylation of the p70 S6 kinase. In addition to these Kinases, however, phosphorylation of the p70 S6 kinase by other as yet unidentified Protein Kinases is necessary to recapitulate the multisite phosphorylation required for activation of the p70 S6 kinase.
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Insulin-activated Protein Kinases phosphorylate a pseudosubstrate synthetic peptide inhibitor of the p70 S6 kinase.
The Journal of biological chemistry, 1991Co-Authors: D J Price, N K Mukhopadhyay, J AvruchAbstract:p70 S6 kinase, a major insulin-mitogen-activated ribosomal S6 Protein kinase in mammalian cells, is activated by phosphorylation of multiple Ser/Thr residues on the enzyme polypeptide. A synthetic peptide, corresponding to a 37-residue segment from the carboxyl-terminal tail of the kinase which resembles the sequence phosphorylated in S6, acts as a competitive inhibitor of p70 S6 kinase without itself being phosphorylated by the enzyme. This synthetic peptide is phosphorylated by an array of Protein Kinases which are rapidly activated by insulin. Thus, these sequences of p70 S6 kinase constitute a potential autoinhibitory pseudosubstrate site, whose phosphorylation is catalyzed by candidate upstream-activating Protein Kinases.
D J Price - One of the best experts on this subject based on the ideXlab platform.
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an array of insulin activated proline directed serine threonine Protein Kinases phosphorylate the p70 s6 kinase
Journal of Biological Chemistry, 1992Co-Authors: N K Mukhopadhyay, D J Price, J M Kyriakis, S Pelech, J Sanghera, J AvruchAbstract:Abstract This study characterizes the insulin-activated serine/threonine Protein Kinases in H4 hepatoma cells active on a 37-residue synthetic peptide (called the SKAIPS peptide) corresponding to a putative autoinhibitory domain in the carboxyl-terminal tail of the p70 S6 kinase as well as on recombinant p70 S6 kinase. Three peaks of insulin-stimulated Protein kinase active on both these substrates are identified as two (possibly three) isoforms of the 40-45-kDa erk/microtubule-associated Protein (MAP)-2 kinase family and a 150-kDa form of cdc2. Although distinguishable in their substrate specificity, these Protein Kinases together with the p54 MAP-2 kinase share a major common specificity determinant reflected in the SKAIPS peptide: the requirement for a proline residue immediately carboxyl-terminal to the site of Ser/Thr phosphorylation. In addition, however, at least one peak of insulin-stimulated Protein kinase active on recombinant p70, but not on the SKAIPS peptide, is present although not yet identified. MFP/cdc2 phosphorylates both rat liver p70 S6 kinase and recombinant p70 S6 kinase exclusively at a set of Ser/Thr residues within the putative autoinhibitory (SKAIPS peptide) domain. erk/MAP kinase does not phosphorylate rat liver p70 S6 kinase, but readily phosphorylates recombinant p70 S6 kinase at sites both within and in addition to those encompassed by the SKAIPS peptide sequences. Although the tryptic 32P-peptides bearing the cdc2 and erk/MAP kinase phosphorylation sites co-migrate with a subset of the sites phosphorylated in situ in insulin-stimulated cells, phosphorylation of the p70 S6 kinase by these proline-directed Protein Kinases in vitro does not reproducibly activate p70 S6 kinase activity. Thus, one or more erk/MAP Kinases and cdc2 are likely to participate in the insulin-induced phosphorylation of the p70 S6 kinase. In addition to these Kinases, however, phosphorylation of the p70 S6 kinase by other as yet unidentified Protein Kinases is necessary to recapitulate the multisite phosphorylation required for activation of the p70 S6 kinase.
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Insulin-activated Protein Kinases phosphorylate a pseudosubstrate synthetic peptide inhibitor of the p70 S6 kinase.
The Journal of biological chemistry, 1991Co-Authors: D J Price, N K Mukhopadhyay, J AvruchAbstract:p70 S6 kinase, a major insulin-mitogen-activated ribosomal S6 Protein kinase in mammalian cells, is activated by phosphorylation of multiple Ser/Thr residues on the enzyme polypeptide. A synthetic peptide, corresponding to a 37-residue segment from the carboxyl-terminal tail of the kinase which resembles the sequence phosphorylated in S6, acts as a competitive inhibitor of p70 S6 kinase without itself being phosphorylated by the enzyme. This synthetic peptide is phosphorylated by an array of Protein Kinases which are rapidly activated by insulin. Thus, these sequences of p70 S6 kinase constitute a potential autoinhibitory pseudosubstrate site, whose phosphorylation is catalyzed by candidate upstream-activating Protein Kinases.
