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

Leydig-cell suspensions, prepared from rat testes, were incubated with different amounts of Ca2+ with and without added luteinizing hormone. The basal testosterone production in the absence of luteinizing hormone was unaffected by the Ca2+ concentration in the incubation medium. The luteinizing hormone-stimulated testosterone production, however, was progressively decreased in the absence of Ca2+ to one-third of that with 2.50 mM-Ca2+. This decrease in luteinizing hormone-stimulated testosterone production was independent of the different concentrations of luteinizing hormone (0-10mug/ml) used and could be restored by the addition of Ca2+ to the incubation medium. The restoration of the stimulation was achieved within 30 min after the addition of Ca2+ to the medium. Activation of cyclic AMP-dependent protein kinase by luteinizing hormone was not decreased by omission of Ca2+ from the incubation medium, suggesting that Ca2+ may be involved in steroidogenesis at a stage beyond the luteinizing hormone receptor-adenylate cyclase-protein kinase system.
Biochem J 1976 Dec 15
PMID:The effect of calcium ions on testosterone production in Leydig cells from rat testis. 101 34

Both cytosol and mitochondria of rat liver display protein kinase activity, cyclic AMP-independent, which is resolved by Sepharose 6B filtration and P-cellulose chromatography into multiple forms phosphorylating, besides endogenous mitochondrial membrane-bound proteins, also exogenous phosphoproteins such as casein and phosvitin. However, the forms by far predominant in the cytosol phosphorylate both phosphorylserine and phosphorylthreonine residues of casein, while most of the activity associated to mitochondrial structures is due to the forms phosphorylating only phosphorylserine residues.
Biochim Biophys Acta 1976 Dec 21
PMID:Comparative study of mitochondrial and cytosol protein kinase activities. 103 67

The heme-regulated translational inhibitor (HRI) has been purified 4800-fold. On electrophoresis in sodium dodecyl sulfate/polyacrylamide gel, the purified HRI showed one major polypeptide band. The purified HRI inhibits protein synthesis in lysates containing optimal levels of hemin with inhibition kinetics which parallel those observed in heme-deficiency. Data are presented which are consistent with an enzymatic function of HRI in the inhibition of protein synthesis. The HRI is an adenosine 3':5'-cyclic monophosphate independent protein kinase which phosphorylates the small subunit (38,000) but not the large subunits (52,000 and 50,000) of the initiation factor which forms a ternary complex with Met-tRNAf and GTP. This evidence supports the hypothesis that inhibition of protein synthesis by HRI involves the phosphorylation of the initiation factor. These findings are discussed in relation to various models for the regulation of protein kinase activity by heme. (see article).
Proc Natl Acad Sci U S A 1976 Dec
PMID:Regulation of protein synthesis in rabbit reticulocyte lysates: purification and initial characterization of the cyclic 3':5'-AMP independent protein kinase of the heme-regulated translational inhibitor. 106 87

The regulatory effect of thyroid hormone on cardiac protein kinase activity and ATP hydrolysis was studied in developing rats. Experimental hypothyroidism induced by a single intraperitoneal injection of 200 muCi of 131I led to a significant impairment of body and heart growth and elevated the activity of membrane-bound protein kinase (measured in the absence of cyclic AMP). However, a slight (11%) but statistically non-significant decrease was observed in soluble protein kinase activity in hearts of hypothyroid rats. Furthermore, thyroid deficiency produced in neonatal life significantly decreased (34%) the rate of cardiac ATP hydrolysis. Treatment of thyroidectomized animals with L-triiodothyronine initiated early in life produced a time-dependent increase in heart weight as well as the activity of soluble protein kinase and the rate of ATP hydrolysis in cardiac tissue. Maximal rise in these parameters was observed in hypothyroid rats receiving L-triiodothyronine treatment for 24 days beginning from 7 days after radioiodine injection. These animals also showed a marked cardiac hypertrophy. In contrast, replacement therapy with L-triiodothyronine produced a decrease in the activity of the membrane-bound protein kinase, which seemed to be inversely proportional to the duration of L-triiodothyronine treatment. Our data provide evidence suggesting that thyroid hormone plays an important role in controlling ATP turnover in hearts of developing rats.
Res Commun Chem Pathol Pharmacol 1975 Dec
PMID:Effect of radio-thyroidectomy and thyroid hormone replacement therapy on cardiac protein kinase activity and ATP hydrolysis. 121 63

We have examined the effects of protein kinase-C (PKC) activation on expression of the six known insulin-like growth factor-binding proteins (IGFBPs) by human endometrial carcinoma cells. Each of six known IGFBPs was expressed in one or more of the three cell lines examined. The addition of 10(-7) M 4 beta-phorbol 12-myristate 13-acetate (PMA) to HEC-50 and HEC-1B cells resulted in changes in cell morphology, growth inhibition, activation of PKC, and an increase in expression of IGFBP-1. PMA had no effect on these parameters in the Ishikawa cell line, which did not express IGFBP-1. In HEC-50 cells, the effect of PMA was blocked by the concomitant addition of the PKC inhibitor staurosporin and the simultaneous addition of cycloheximide. PMA also resulted in an increase in IGFBP-3 in HEC-50 cells and an increase in IGFBP-6 expression in HEC-1B cells. In contrast, IGFBP-3 expression was down-regulated by PMA in HEC-1B and Ishikawa cells. The abundance of IGFBP-2 and IGFBP-5 mRNAs was also reduced in HEC-1B and Ishikawa cells, respectively. IGFBP-4 was expressed only in HEC-50 cells and was not affected by PMA treatment. These data establish a role for the PKC pathway in regulation of expression of IGFBP-1, -2, -3, and -5 in endometrial adenocarcinoma cells and illustrate the complexity of cell type-specific expression of the IGFBPs.
Endocrinology 1992 Dec
PMID:Phorbol esters differentially regulate the expression of insulin-like growth factor-binding proteins in endometrial carcinoma cells. 128 Feb 5

In order to directly evaluate the role of the cAMP-dependent protein kinase (PKA) catalytic (C) subunit in T-cell receptor- (TCR) triggered cytotoxic T-lymphocytes (CTL) effector functions, cells were studied after pretreatment with antisense oligomers complementary to mRNA for the C alpha or C beta subunits. C alpha subunit is shown to be predominantly expressed in CTL. In some experiments the pretreatment of the CTL with the C alpha antisense, but not with the control or C beta antisense oligomers, resulted in the inhibition of cAMP-independent PKA activity without significantly affecting the level of total cAMP-inducible PKA activity. In parallel assays, CTL which were pretreated with the C alpha antisense oligomer had enhanced antigen-bearing target cell-triggered-, anti-TCR monoclonal antibody-triggered-, and phorbol 12-myristate 13-acetate/A23187-triggered exocytosis of granules, as well as enhanced antigen-specific cytotoxicity. In contrast, the TCR-triggered gamma-interferon mRNA expression and gamma-interferon secretion were inhibited in C alpha antisense-pretreated CTL. These results suggest that the C alpha subunit of PKA may have a dual role in regulation of T-lymphocytes effector functions: (i) it may down-regulate TCR-triggered protein-synthesis independent responses such as cytotoxicity and exocytosis, thereby counteracting TCR-triggered activation even in the absence of the second messenger, cAMP, and (ii) the C alpha subunit activity is likely to be required for the nuclear and/or cytoplasmic events in CTL's activation involved in lymphokine synthesis and secretion.
J Biol Chem 1992 Dec 15
PMID:The dual role of the cAMP-dependent protein kinase C alpha subunit in T-cell receptor-triggered T-lymphocytes effector functions. 128 Nov 54

The effect of a cAMP-dependent secretogogue (VIP) on the phosphorylation of an endogenous, membrane-bound protein (pp170) was assessed in an intact cell preparation from the avian salt gland. The addition of VIP, in the presence of 100 microM isobutylmethylxanthine, resulted in a concentration-dependent increase in phosphorylation of pp170. This effect was rapid and transient with a 3-5-fold increase in phosphorylation occurring 1 min after the addition of VIP. Under similar incubation conditions, VIP stimulated a 4.6-fold increase in cAMP accumulation that paralleled phosphorylation. Exposure of cells to either forskolin or 8-Br-cAMP resulted in a 5-8-fold increase in the phosphorylation of pp170. The effect of forskolin was dose dependent with an EC50 similar to that for stimulation of secretion (35 nM). These results implicate an involvement for a cAMP-dependent protein kinase in the phosphorylation of pp170. The identity of pp170 was assessed utilizing a monoclonal antibody (Q3) directed against pp170. Q3 recognized a single 170-kDa band on Western blots of salt gland membrane protein. Immunoprecipitation of pp170 from salt gland cells resulted in the selective extraction of a single protein whose phosphorylation state was increased approximately 5-fold in response to carbachol or VIP. The identity of pp170 was established using two criteria. First, Q3 recognized affinity-purified Na:K:Cl cotransporter preparations from shark rectal gland membranes. Second, pp170 was selectively immunoprecipitated by monoclonal antibodies (J3, J4, and J7) that recognize different epitopes of the shark transport protein. These results suggest that pp170 is homologous to the shark rectal gland Na-K-Cl cotransporter, and thus the proteins may be functionally similar.
J Biol Chem 1992 Dec 15
PMID:The Na-K-Cl cotransporter of avian salt gland. Phosphorylation in response to cAMP-dependent and calcium-dependent secretogogues. 128 Nov 59

We have used the polymerase chain reaction (PCR) technique to clone kinase-related sequences from avian blastula, neural crest and neural tube mRNA. Twenty-three distinct protein kinase (PK) sequences were amplified, of which eight are identical to previously described PK genes. The cloned molecules fall into three classes: growth factor receptor tyrosine kinases (RTKs), cytosolic tyrosine kinases and serine/threonine kinases. Among the cloned RTKs were the insulin-like growth factor type I receptor, platelet-derived growth factor receptor alpha, the CEK1 fibroblast growth factor (FGF) receptor as well as the avian homolog of a recently cloned PCR fragment related to the eph/elk/eck family, tyro-5. Furthermore, we cloned a novel FGF receptor-like molecule as well as two novel putative RTKs related to the vascular endothelial growth factor (VEGF) receptor. The pattern of expression of the PCR clones was examined by Northern blot analysis of adult tissues: each molecule recognized one or more transcripts of various sizes, suggesting that PK genes may play regulatory roles both in early development and in adult regulation of tissue function. Together with recent studies, this survey confirms the hypothesis that PKs may play important roles in early vertebrate development.
Oncogene 1992 Dec
PMID:Molecular cloning of a family of protein kinase genes expressed in the avian embryo. 128 6

Mitogen-activated protein (MAP) kinase kinases, intermediates in a growth factor-stimulated protein kinase cascade, are dual specificity protein kinases that specifically phosphorylate and activate MAP kinases in response to extracellular signals. Here, we report the cloning of two forms of cDNA that encode this protein from human T-cells. MKK1a encodes a protein with predicted molecular size of 43,439 Da. Overexpression of this clone in COS cells led to elevated levels of protein and phorbol ester-stimulated MAP kinase kinase activity, confirming that MKK1a encodes the predicted protein. MKK1b, which appears to be an alternatively spliced form of the MKK1a gene, encodes a protein with predicted molecular size of 40,745 Da. Northern analysis revealed that the MKK1 cDNA hybridizes with a single 2.6-kilobase mRNA species in all human tissues examined. Sequence comparison shows homology to a group of yeast kinases that participate in signal transduction and to subdomain XI of other dual specificity kinase.
J Biol Chem 1992 Dec 25
PMID:Human T-cell mitogen-activated protein kinase kinases are related to yeast signal transduction kinases. 128 67

Incubation of Swiss 3T3 or L929 cells with tumor necrosis factor (TNF) leads to the rapid stimulation of several cytosolic Ser/Thr kinases active toward myelin basic protein, the S6 peptide (RRLSSLR), the G peptide (SPQPSRRGSESSEE), and Kemptide (LRRASLG). This confirms the hypothesis that kinases other than protein kinases A and C may be involved in the TNF signal transduction. Chromatography on Mono Q resolved multiple kinase peaks with each substrate tested and moreover revealed a TNF-mediated casein kinase-2 activation in both cell lines, measurable with the specific RRREEESEEE peptide or with the G peptide. The TNF-stimulated myelin basic protein kinases-1 and -2 were identified as extracellular signal-regulated kinases-2 and -1, respectively, based on their elution pattern on Mono Q chromatography, their inactivation by protein phosphatase action, their reaction with phosphothreonine and phosphotyrosine antibodies, and by their migration on sodium dodecyl sulfate-polyacrylamide gel electrophoresis as 42- and 44-kDa proteins recognized by anti-extracellular signal-regulated kinase antibodies.
J Biol Chem 1992 Dec 25
PMID:Tumor necrosis factor stimulates multiple serine/threonine protein kinases in Swiss 3T3 and L929 cells. Implication of casein kinase-2 and extracellular signal-regulated kinases in the tumor necrosis factor signal transduction pathway. 128 78


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