Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:2.7.11.1 (protein kinase)
 81,284 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Tumor necrosis factor (TNF) has been shown to bind two distinct receptors, designated p60 and p80, with high affinity, resulting, within minutes, in phosphorylation of several proteins. The receptors themselves do not exhibit protein kinase activity nor have any associated proteins been identified. We employed the glutathione-S-transferase (GST) fusion protein system consisting of the cytoplasmic domain of p60 (GST-p60CD delta 1) as a probe to help us identify receptor-associated proteins from human histiocytic lymphoma U-937 cells. We found that a protein of approximately 52 kDa (pp52) bound to GST-p60CD delta 1 from [35S]methionine- and 32P-labeled cells. The associated protein was phosphorylated on serine and threonine residues. Furthermore, we identified serine/threonine kinase activity associated with p60CD delta 1 that required either Mn2+ or Mg2+ for optimal activity. The preferred substrates for this kinase, in addition to p60CD delta 1, included casein and histone H1, but not histone H2B, myelin basic protein, enolase, or the cytoplasmic domain of p80. As was the case in U-937 cells, p60CD delta 1-associated kinase activity was also identified in human breast adenocarcinoma MCF-7 cells and human foreskin fibroblasts. TNF stimulation of MCF-7 and foreskin fibroblasts for 5-15 min induced approximately 50 and 240% increases in phosphorylation of p60CD delta 1, respectively. Thus, our results provide the first evidence for protein kinase activity that is specifically associated with the cytoplasmic domain of the p60 form of the TNF receptor and causes its phosphorylation. This p60 TNF receptor-associated protein and the associated kinase described here are referred to as p60-TRAP and p60-TRAK, respectively.
 ...
PMID:Identification of a protein kinase associated with the cytoplasmic domain of the p60 tumor necrosis factor receptor. 805 Nov 24

The major tyrosine protein kinase, HPK40, isolated from HL-60, the preparation of which is described elsewhere (Ernould, A.P., Ferry, G., Barret, J.M., Genton, A. and Boutin, J.A., Eur. J. Biochem., 214, 503-514), was investigated as to its specificity on a number of peptides and proteins. It was found that HPK40 can phosphorylate histones (except histone H4), casein, acid-treated enolase, actin and tubulin but not calmodulin. Phosphorylation specificity of HPK40 was investigated using over a hundred peptidic structures. HPK40 is not related to the 'src' family and does not phosphorylate efficiently either the tetrapeptide NEYT derived from the pp60src autophosphorylation domain or the corresponding peptide RRsrc, RRLIED-NEYTARG. VALYDYESR from the SH3 domain of pp60c-src is recognized as a substrate with a high phosphorylation level. DEDYIQD, derived from the phosvitin/casein kinase II, was also highly phosphorylated. In order to determine the minimal recognition sequence of HPK40, the phosphorylation of about 60 dito tetrapeptides was investigated. Some of the tetrapeptides, such as *EEYE and NEYE, were well phosphorylated. Even some tripeptides, such as EYE, DYM, TYS and KYE, were recognized by HPK40, while none of the tested dipeptides was recognized as substrate. Sequences of peptides from DRVYHPF (angiotensin), LEEEEEAYGWMDF (minigastrin) and QEEYSAM (from H-ras1) were examined as substrates. The presence of one or several acidic residues on the N alpha-side of tyrosine residue was identified as the only apparently favorable determinant.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Substrate phosphorylation capacities of the major tyrosine protein kinase from the human promyelocytic cell line, HL-60. 807 Sep 74

The environmental signals which regulate the development of central noradrenergic neurons are largely unknown. The aim of the present study was to search for factors affecting the development of these cells. Dissociated cultures of embryonic dorsal brainstem tissue, containing the nucleus locus coeruleus (LC), were established; norepinephrine (NE) and GABA uptake were assessed, and noradrenergic versus total neurons were identified and counted following immunocytochemical staining with tyrosine hydroxylase (TH) and neuron specific enolase (NSE) antibodies, respectively. Application of dibutyryl cAMP (dbcAMP), other cAMP analogs, or forskolin, to LC cultures resulted in a significant increase in NE uptake which was associated with up to a 4-fold increase in the number of TH immunoreactive cells (TH+). dbcAMP treatment caused an increase in the number of TH+ cells in LC cultures by enhancing their survival and/or by upregulating their phenotypic differentiation. A possible effect of dbcAMP on cell proliferation and transformation of non-noradrenergic cells to noradrenergic TH+ cells were examined and suggested not to underlie this effect of cAMP. Glial cells may mediate the effect of cAMP on noradrenergic neurons. Calcium was not involved in the trophic activity of dbcAMP, which was probably mediated by protein phosphorylation via cAMP dependent protein kinase. Insulin (25 micrograms/ml) was found to increase the number of TH+ cells by 73%. The beta-adrenergic agonist isoproterenol also increased the number of TH+ cells by 53%. We propose a neurotrophic role for NE during development of central noradrenergic neurons.
 ...
PMID:Neurotrophic effects of cAMP generating systems on central noradrenergic neurons. 810 14

The addition of IL-6 to the IL-6-dependent B9-55 hybridoma cells starved for IL-6 for 16 h induced an increased phosphorylation of a 25-kda protein (p25). Phosphorylation of p25 was IL-6 dependent and maximal at 5 min after IL-6 stimulation. Phosphorylation of p25 was inhibited by N-(6-aminohexyl)-5-chloro-1-naphthalene sulfonamide (W-7), an inhibitor of calmodulin-dependent protein kinase, but not by tyrphostin nor ionomycin. When enolase was used as an exogenous substrate, similar results were obtained. Furthermore, calmodulin stimulated p25 phosphorylation in vitro. IL-6-starved B9 hybridoma cells synthesized DNA at 9 to 12 h after addition of IL-6. Preincubation of cells with W-7 before IL-6 stimulation blocked DNA synthesis. Similar effects were observed when cells were preincubated with tyrphostin or ionomycin but to a lesser extent. The concentrations of W-7 required for blocking p25 phosphorylation and DNA synthesis correlated relatively well. These results suggest that an IL-6-inducible calmodulin-dependent protein kinase is involved in IL-6 signal transduction, including p25 phosphorylation and B9 hybridoma proliferation.
 ...
PMID:IL-6-induced calmodulin-dependent protein phosphorylation in B9 hybridoma cells. 812 Mar 67

We have isolated two yeast genes, KIN1 and KIN2, by their homology to the protein kinase family of viral oncogenes. Previous studies have identified the yeast KIN1 gene product (pp145KIN1) as a 145 kilodalton (kDa) phosphoprotein with serine/threonine-specific protein kinase activity. To identify and biochemically characterize the KIN2 gene product, antibodies were raised against a bacterial beta-galactosidase/KIN2 fusion polypeptide. In vivo, the KIN2 gene product is a 145 kDa phosphoprotein, pp145KIN2. In immune complexes, pp145KIN2 demonstrates serine/threonine protein kinase activity, transferring phosphate from [gamma-32P]ATP to either itself or the exogenously added substrates alpha-casein, acid-denatured enolase, or phosvitin. In vitro, kinase activity is dependent on either Mn2+ or Mg2+ ions. Both enzymes, pp145KIN1 and pp145KIN2, prefer ATP over GTP as their phosphoryl donor. Since a new class of yeast protein kinases has been identified which are serine/tyrosine-specific, we analysed a wide range of substrates to see if any could be phosphorylated by pp145KIN1 or pp145KIN2 on tyrosine residues. Both enzymes phosphorylate alpha-casein, acid-denatured enolase, and phosvitin on serine and threonine residues. Neither enzyme could phosphorylate tyrosine residues even though good substrates for tyrosine-specific kinases such as enolase, angiotensin II, and the synthetic polymer GLU80TYR20 were used. The biochemical analysis of KIN2 kinase activity shows remarkable similarity to that of its most closely related yeast kinase, KIN1. It remains to be seen if these two yeast protein kinases share any functional relationships or substrates in vivo.
 ...
PMID:Characterization of the KIN2 gene product in Saccharomyces cerevisiae and comparison between the kinase activities of p145KIN1 and p145KIN2. 820 45

We report the cloning of the full-length cDNA of a new murine protein kinase, mPKL12. The sequence reveals a 305-amino-acid protein that contains the characteristic subdomains of the kinase superfamily and particular homology indicating a ser/thr specificity. We have also identified its human homologue gene (94% identical) and the putative homologue proteins from Saccharomyces cerevisiae and Arabidoposis thaliana. These four sequences appear to form a new subfamily of protein kinases, close in size to the theoretical minimal catalytic domain, therefore suggesting that they could be the catalytic unit of a more complex holoenzyme. Using Escherichia coli-purified protein, we have demonstrated that the mPKL12 enzyme possesses an intrinsic kinase activity, capable of phosphorylating enolase and also of promoting autophosphorylation, with a ser/thr specificity. Tissue expression analysis of mPKL12 showed that it is ubiquitously expressed, although at very low levels. RT-PCR analysis of several cell lines also supports this view, therefore suggesting that PKL12 may play a role in a very general cellular function, probably related with the secretory pathway.
 ...
PMID:Cloning, expression analysis, and functional characterization of PKL12, a member of a new subfamily of ser/thr kinases. 971 5

We have developed a general strategy for designing efficient protein substrates of protein kinases by attaching a phosphorylatable peptide sequence to the C-terminus of His6-tagged green fluorescent protein (GFP). We found that several C-terminal attachment sites in GFP allow for correct presentation of the phosphorylatable tail to a variety of protein kinases. Using this strategy, we have constructed highly efficient GFP-based substrates for Src, c-Abl, protein kinase A, and protein kinase C betaII protein kinases. The engineered GFP substrate for Src (GFP235IYGEFG) is 300 times more efficient than the protein most commonly used as a Src substrate-rabbit muscle enolase.
 ...
PMID:Highly efficient green fluorescent protein-based kinase substrates. 988 72

The protein encoded by the U69 open reading frame (ORF) of human herpesvirus 6 (HHV-6) has been predicted to be a protein kinase. To investigate its functional properties, we have expressed the U69 ORFs from both HHV-6 variants, A and B, by using recombinant baculoviruses (BV6AU69 and BV6BU69). Nickel agarose and antibody affinity chromatography was used to purify the proteins to homogeneity and when incubated with [gamma-32P]ATP, both U69 proteins became phosphorylated on predominantly serine residues. These data strongly suggest that U69 is a protein kinase which autophosphorylates. The phosphorylation reaction was optimal at physiological pH and low NaCl concentrations. It required the presence of Mg2+ or Mn2+, and Mg2+ was able to support phosphorylation over a wider range of concentrations than Mn2+. Both ATP and GTP could donate phosphate in the protein kinase assay and the former was more efficient. U69 was capable of phosphorylating histone and casein (serine/threonine kinase substrates) but not enolase (a tyrosine kinase substrate). For the autophosphorylation reaction, the Michaelis constants for ATP of baculovirus-expressed HHV-6A and HHV-6B U69 were calculated to be 44 and 11 microM, respectively. U69 is a homologue of the UL97 gene encoded by human cytomegalovirus which has been shown to phosphorylate the antiviral drug ganciclovir (GCV). We analyzed whether the U69 ORF alone was capable of conferring GCV sensitivity on baculoviruses BV6AU69 and BV6BU69. In plaque reduction experiments, these baculoviruses displayed a GCV-sensitive phenotype compared to a control baculovirus (BVLacZ). The 50% inhibitory concentrations (IC50) of BV6AU69 and BV6BU69 were calculated to be 0.35 and 0.26 mM, respectively, whereas the control baculovirus had an IC50 of >1.4 mM. This shows that the U69 gene product is the only one required to confer GCV sensitivity on baculovirus.
 ...
PMID:The U69 gene of human herpesvirus 6 encodes a protein kinase which can confer ganciclovir sensitivity to baculoviruses. 1007 82

Directional tag PCR subtractive hybridization was applied to construct a cDNA library generated from three different human osteosarcoma (OS) target cell lines (OHS, SaOS-2 and KPDXM) from which normal osteoblast (NO) sequences were subtracted. After two consecutive subtractive steps more than 98% of the common mRNAs species were depleted, leading to effective enrichment of the remaining target sequences. After differential screening of 960 clones, 81 candidates were further studied by Northern blot analysis and 73 represented separate mRNA species. Fifty-three of these showed enriched mRNA levels, of which 36 represented known and 17 not previously published cDNAs or EST sequences. The mRNAs showed a 1.4- to 504-fold enrichment compared to the mRNA levels in NO cells. The known mRNAs are: Ribosomal protein S11, KSP-37, Tethering factor SEC34, FXYD6, Alpha enolase, G-s-alpha, GPR85, DAF, RPL35A, GIF, TAPA-1, ANAPC11, DCI, hsp27, MRPS7 homolog, eIF p110 subunit, DPH2L, HMG-14, FB1 protein, chondroitin-6-sulphonase, calgizzarin, RNA polymerase II subunit, RPL13A, DHS, gp96, HHP2, acidic ribosomal phosphoprotein P2, ANT-2, ARF1, AFG3L2, SKD3, phosphoglucoisomerase, GST pi, CKI gamma 2, DNA polymerase delta small subunit and TRAP delta. Sections of human osteosarcoma biopsies and a xenograft were studied by in situ analysis. Seven cDNAs highly expressed in Northern blot analysis were tested. Their in situ expression differed between the xenograft and human sections as did that of collagen I. In the xenograft made from one of the target cell lines (OHS), a fair to strong representation of 3 cloned mRNAs was observed while collagen I mRNA was not detectable. We conclude that the molecular heterogeneity of these tumors is considerable. These results ought to have implications for future work to describe phenotypic subtypes with the aim of improving the diagnosis of human osteosarcomas.
 ...
PMID:Molecular heterogeneity in human osteosarcoma demonstrated by enriched mRNAs isolated by directional tag PCR subtraction cloning. 1289 94

The authors have engineered plasmid constructs for developmental and constitutive expression of yeast-enhanced green fluorescent protein (yEGFP3) in Candida albicans. The promoter for the hyphae-specific gene Hyphal Wall Protein 1 (HWP1) conferred developmental expression of yEGFP3 in germ tubes and hyphae but not in yeasts or pseudohyphae when targeted to the ENO1 (enolase) locus in single copy. The pHWP1GFP3 construct allows for the easy visualization of HWP1 promoter activity in individual cells expressing true hyphae without having to prepare RNA for analysis. Constitutive expression of yEGFP was seen in all cell morphologies when the HWP1 promoter was replaced with the ENO1 promoter region. The use of the plasmids for expression of genes other than yEGFP3 was examined by substituting the putative C. albicans BCY1 (SRA1) gene, a component of the cAMP signalling pathway involved in yeast to hyphae transitions, for yEGFP3. Strains overexpressing BCY1 from the ENO1 promoter were inhibited in germ tube formation and filamentation in both liquid and solid media, a phenotype consistent with keeping protein kinase A in its inactive form by association with Bcy1p. The plasmids are suitable for studies of germ tube induction or assessing germ tube formation by measuring yEGFP3 expression, for inducible expression of genes concomitant with germ tube formation by the HWP1 promoter, for constitutive expression of genes by the ENO1 promoter, and for expressing yEGFP3 using a promoter of choice.
 ...
PMID:Integrative, multifunctional plasmids for hypha-specific or constitutive expression of green fluorescent protein in Candida albicans. 1452 29


<< Previous 1 2 3 4 5 6 Next >>