Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.3.16 (calcineurin)
 17,112 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The heterogeneity of phosphoprotein phosphohydrolase--Fpf in cellular free spleen extracts of pigs may be determined by sodium fluoride inhibition. NaF concentration of 5 X 10(-3) mol/l divides Fpf into 3 groups and shows a wide inhibition range from 15 to 85% of the initial activity of the enzyme. Naf concentration of 5 X 10(-4)mol/l stops Fpf activity in the range from 10 to 65% and divides it into two groups. To classify the studied material into Fpf phenotypes, fluoride quotient index--WIF has been proposed which expresses the relationship between the percentage of the inhibition caused by NaF at a concentration 5 X 10(-3) mol/l and that of the inhibition caused by NaF at a concentration of 5 X 10(-4) mol/l in the reaction mixture and in the measurement conditions described in the methods. Five groups with the following numerical values of WIF have been distinguished: 1.15 less than or equal to WIF less than 1.40-44%--group I; 1.50 less than or equal to WIF less than 1.80-20%--group II; 1.90 less than or equal to WIF less than 2.10-16%--group III; 2.20 less than or equal to WIF less than 2.50-16%--group IV; and WIF = 3-4%--group V.
Pol Arch Weter 1986
PMID:[Demonstration and classification of heterogeneity of phosphoprotein phosphohydrolase in swine spleen extracts based on sodium fluoride inhibition]. 303 62

Phosphoprotein phosphatase was isolated from yeast postribosomal supernatant and partly characterized. The enzyme preferentially dephosphorylated phospho-casein and acidic ribosomal proteins L44 and L45, the eukaryotic analogues of bacterial proteins L7 and L12. The evidence suggests that this enzyme is not a catalytic subunit of the multifunctional phosphoprotein phosphatase present in most eukaryotic organisms.
Acta Biochim Pol 1983
PMID:Phosphoprotein phosphatase from yeast and its ribosomal substrate. 630 65

B-50/GAP-43 is a growth-associated phosphoprotein enriched in growth cones and in the presynaptic terminal. The expression of the protein is restricted to the nervous system and is highest in the first week after birth. In adult brain, B-50 is enriched in areas with high plasticity. The regulation of expression of the B-50 gene occurs both at the transcriptional and post-transcriptional level by unknown mechanisms. The gene contains 2 regions displaying promoter activity, the most 3' of which (P2) is the active on in vivo. Expression of B-50 in non-neuronal cells results in filopodial extensions whereas antibodies or antisense oligo's to B-50 prevent neurite outgrowth. The protein is important for neuronal pathfinding. Several post-translational modifications have been described, ADP-ribosylation and palmitoylation in the membrane binding domain, phosphorylation by PKC, casein kinase II and phosphorylase kinase, and dephosphorylation by several phosphatases, among which is calcineurin. Interactions of B-50 have been described with calmodulin, PIP kinase, F-actin, and phospholipids. Recent studies indicate that the phosphorylation state and amount of calmodulin bound to B-50 regulate the rate of transmitter release. Induction of long-term potentiation by high frequency stimulation of hippocampal slices results in an increased state of B-50 phosphorylation. This will increase the amount of free calmodulin in the presynaptic terminal and increase the amount of transmitter released. Although B-50 is involved in seemingly unrelated forms of neuronal plasticity, neurite outgrowth and transmitter release, our unifying hypothesis is that the protein plays an (unknown) essential, modulatory role in membrane expansion.
Acta Biochim Pol 1996
PMID:Presynaptic phosphoprotein B-50/GAP-43 in neuronal and synaptic plasticity. 886 78

Alterations in gene expression may represent an underlying cause of undesired side-effects mediated by the immunosuppressant cyclosporin A (CsA). We employed the method of differential display PCR to identify new genes whose expression is modulated by CsA. Human peripheral blood mononuclear cells (PBMCs), or subpopulations thereof, were simultaneously stimulated with the phorbol ester 4beta-phorbol 12-myristate 13-acetate (PMA) and the calcium ionophore ionomycin, in the presence or absence of therapeutic concentrations of CsA. We identify the gene encoding the DNA repair enzyme DNA polymerase beta (Pol beta) as a novel CsA-sensitive transcription unit. Our data show that transcription of pol beta mRNA is induced by Ca2+ and that CsA significantly inhibits PMA/ionomycin- and ionomycin-mediated upregulation of both pol beta mRNA and Pol beta protein. The CsA-mediated inhibition of pol beta upregulation is maintained for at least 21 h after gene activation and is exerted via the phosphatase calcineurin. FK506, another immunosuppressant that targets calcineurin, also inhibits pol beta upregulation, while rapamycin competes with FK506 action. This work identifies Ca2+ as an inducer of pol beta gene activity in primary blood cells. The demonstrated CsA sensitivity of this process suggests a novel molecular mechanism that may contribute to the increased tumor incidence in patients receiving CsA treatment.
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PMID:Cyclosporin A inhibits Ca2+-mediated upregulation of the DNA repair enzyme DNA polymerase beta in human peripheral blood mononuclear cells. 1049 Nov 44

The presence of protein kinase activity and its phosphorylated products has been demonstrated on the outer surface of the plasma membrane of endothelial cells. Extracellular phosphorylation was detected by incubation of primary endothelial cells (HUVEC's) and endothelial cell line EA.hy 926 with [gamma-32P]ATP. The reaction products were subjected to SDS/PAGE, autoradiography and scanning densitometry. Under the experimental conditions, five proteins with apparent molecular masses of 19, 23, 55, 88, and 110 kDa were prominently phosphorylated in both types of cells. Phosphorylation of the 19 kDa protein was the most rapid reaching maximum after 60 s and then the protein became dephosphorylated. Ecto-protein kinases responsible for the surface labeling of membrane proteins were characterized by using (a) protein kinase C inhibitors: K-252b, chelerythrine chloride, and [Ala113] myelin basic protein (104-118), (b) protein kinase A inhibitor Kemptide 8334, and (c) casein kinase II inhibitor 5,6-dichloro-1-beta-D-ribofuranosyl benzimidazole (DRB). Stimulation of endothelial cells with tumor necrosis factor alpha (TNF alpha) and interferon gamma (IFN gamma) is associated with 20-80% reduction of extracellular phosphorylation of all membrane proteins. IFN gamma bound to membrane receptors becomes rapidly phosphorylated. Only in the case of IFN gamma it was associated with the appearance of a strongly phosphorylated band of 17 kDa corresponding to IFN gamma itself. Phosphorylation of this 17 kDa exogenous substrate was prevented by an ecto-kinase inhibitor K-252b. The existence of ecto-phosphoprotein phosphatase activity in endothelial cells was evidenced by testing the effect of microcystin LR--a membrane impermeable reagent that inhibits both PP-1 and PP-2a phosphoprotein phosphatases. The extent of phosphorylation of 19 kDa and 110 kDa phosphoproteins significantly increased in the presence of microcystin. Our results suggest the presence of at least two ecto-kinase activities on endothelial cells that may play a significant role(s) in the regulation of cytokines function.
Acta Biochim Pol 1999
PMID:Interferon gamma bound to endothelial cells is phosphorylated by ecto-protein kinases. 1069 77

The complete genome sequence of the hyperthermophilic archaeon Pyrococcus abyssi revealed the presence of a family B DNA polymerase (Pol I) and a family D DNA polymerase (Pol II). To extend our knowledge about euryarchaeal DNA polymerases, we cloned the genes encoding these two enzymes and expressed them in Escherichia coli. The DNA polymerases (Pol I and Pol II) were purified to homogeneity and characterized. Pol I had a molecular mass of approximately 90 kDa, as estimated by SDS/PAGE. The optimum pH and Mg(2+) concentration of Pol I were 8.5-9.0 and 3 mm, respectively. Pol II is composed of two subunits that are encoded by two genes arranged in tandem on the P. abyssi genome. We cloned these genes and purified the Pol II DNA polymerase from an E. coli strain coexpressing the cloned genes. The optimum pH and Mg(2+) concentration of Pol II were 6.5 and 15-20 mm, respectively. Both P. abyssi Pol I and Pol II have associated 3'-->5' exonuclease activity although the exonuclease motifs usually found in DNA polymerases are absent in the archaeal family D DNA polymerase sequences. Sequence analysis has revealed that the small subunit of family D DNA polymerase and the Mre11 nucleases belong to the calcineurin-like phosphoesterase superfamily and that residues involved in catalysis and metal coordination in the Mre11 nuclease three-dimensional structure are strictly conserved in both families. One hypothesis is that the phosphoesterase domain of the small subunit is responsible for the 3'-->5' exonuclease activity of family D DNA polymerase. These results increase our understanding of euryarchaeal DNA polymerases and are of importance to push forward the complete understanding of the DNA replication in P. abyssi.
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PMID:Characterization of two DNA polymerases from the hyperthermophilic euryarchaeon Pyrococcus abyssi. 1172 85

Protein phosphatase 2A (PP2A) comprises a diverse family of phosphoserine- and phosphothreonine-specific phosphatases present in all eukaryotic cells. All forms of PP2A contain a catalytic subunit (PP2Ac) which forms a stable complex with the structural subunit PR65/A. The heterodimer PP2Ac-PR65/A associates with regulatory proteins, termed variable subunits, in order to form trimeric holoenzymes attributed with distinct substrate specificity and targeted to different subcellular compartments. PP2Ac activity can be modulated by reversible phosphorylation on Tyr307 and methylation on C-terminal Leu309. Studies on PP2A have shown that this enzyme may be implicated in the regulation of metabolism, transcription, RNA splicing, translation, differentiation, cell cycle, oncogenic transformation and signal transduction.
Acta Biochim Pol 2001
PMID:Protein phosphatase 2A: variety of forms and diversity of functions. 1199 3

Lanthanides, also called rare-earth elements, are an interesting group of 15 chemically active, mainly trivalent, f-electronic, silvery-white metals. In fact, lanthanides are not as rare as the name implies, except for promethium, a radioactive artificial element not found in nature. The mean concentrations of lanthanides in the earth's crust are comparable to those of life-important elements like iodine, cobalt and selenium. Many lanthanide compounds show particular magnetic, catalytic and optic properties, and that is why their technical applications are so extensive. Numerous industrial sources enable lanthanides to penetrate into the human body and therefore detailed toxicological studies of these metals are necessary. In the liver, gadolinium selectively inhibits secretion by Kupffer cells and it decreases cytochrome P450 activity in hepatocytes, thereby protecting liver cells against toxic products of xenobiotic biotransformation. Praseodymium ion (Pr3+) produces the same protective effect in liver tissue cultures. Cytophysiological effects of lanthanides appear to result from the similarity of their cationic radii to the size of Ca2+ ions. Trivalent lanthanide ions, especially La3+ and Gd3+, block different calcium channels in human and animal cells. Lanthanides can affect numerous enzymes: Dy3+ and La3+ block Ca2+-ATPase and Mg2+-ATPase, while Eu3+ and Tb3+ inhibit calcineurin. In neurons, lanthanide ions regulate the transport and release of synaptic transmitters and block some membrane receptors, e.g. GABA and glutamate receptors. It is likely that lanthanides significantly and uniquely affect biochemical pathways, thus altering physiological processes in the tissues of humans and animals.
Acta Biochim Pol 2000
PMID:Toxicological and cytophysiological aspects of lanthanides action. 1199

Diabetes mellitus (DM) is the most common metabolic disease, an independent risk factor of coronary disease, and shortens lifetime in all populations of patients, including kidney transplant recipients. Patients after kidney transplantation are exceptionally predisposed to develop or to exacerbate the preexisting DM. Age, DM in family, CMV infections, genetic factor (HLA A26 and B27), immunosuppressive treatment with steroids or calcineurin inhibitors belong to the major risk factors of diabetes. We analyzed 1300 renal transplant recipients in our center. Out of them 153 suffered from DM. DM de novo revealed 80 pts. Mean age in type I pts was 44.88 years and in type II pts was 57.27 years. De novo diabetics were 56.41 years old in average. CMV infection, potentially pathogenic in development of DM de novo, coexisted in 7.5% of these cases as frequently as in whole TPN population. Most frequently detected HLA antigens were: A2, B8 and DR5. Use of cyclosporine and tacrolimus promoted incidence of DM. We conclude, that low percentage of de novo DM in patients after renal transplantation may result from flexibility in administration of immunosuppressive regimens. Cyclosporine and tacrolimus treatment was switched to sirolimus or mycophenolate mofetil when the glucose intolerance was detected to prevent development of DM.
Pol Merkur Lekarski 2002 Nov
PMID:[Treatment of diabetes mellitus in patients after renal transplantation]. 1262 76

Prevalence of arterial hypertension suddenly rose in patients after renal transplantation since cyclosporine A was introduced. Arterial hypertension is now diagnosed in 67-90% of patients after renal transplantation. It has not only negative effect on cardiovascular system but also shortens survival of renal graft. Ambulatory blood pressure monitoring (ABPM) enables evaluation of diumal profile of BP and efficacy of treatment. This diagnostic tool is very useful in the management of these patients. Nocturnal hypertension was 2.5 times more frequent than daytime elevation of BP in the group of 58 consecutive renal transplant patients treated with calcineurin inhibitors who were assessed by ABPM at our department. Lack of nocturnal dip of BP was observed in most of the patients. Conversion from calcineurin inhibitors (cyclosporine A, tacrolimus) to sirolimus or mycophenolate mofetil may improve BP profile in this group of patients.
Pol Merkur Lekarski 2002 Nov
PMID:[Effect of immunosuppressive treatment on diurnal profile of blood pressure]. 1262 80


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