Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.7.11.12 (PKG)
 2,515 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Two isozymes of cGMP-dependent protein kinase (cGMP kinase) have been identified. Polyclonal antibodies were developed which recognize both isozymes or specifically the I alpha and I beta isoform. The specificity of these antibodies was verified by using the recombinant or purified I alpha and I beta isozymes. The antibodies cross-reacted with the purified isozymes of cGMP kinase from bovine tracheal smooth muscle. The tissue concentration of cGMP kinase was determined by ELISA. High concentrations (greater than 10 pmol/g wet tissue) were present in bovine lung, rumen, trachea, aorta, uterus and stomach. The tissue distribution of the isozymes I alpha and I beta was investigated by immunoblots using crude extracts of the different tissues. The I beta-specific antibody yielded strong signals with extracts of trachea, aorta, stomach and uterus, whereas heart, cerebellum and lung apparently contain mainly the I alpha isozyme.
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PMID:Detection of cGMP dependent protein kinase isozymes by specific antibodies. 132 10

In this study we report the isolation and characterization of three overlapping cDNA clones for the type I beta isozyme of cGMP-dependent protein kinase (cGK) from human placenta libraries. The composite sequence was 3740 nucleotides long and contained 58 nucleotides from the 5'-noncoding region, an open reading frame of 2061 bases including the stop codon, and a 3'-noncoding region of 1621 nucleotides. The predicted full-length human type I beta cGK protein contained 686 amino acids including the initiator methionine, and had an estimated molecular mass of 77,803 Da. On comparison to the published amino acid sequence of bovine lung I alpha, human placenta I beta cGK differed by only two amino acids in the carboxyl-terminal region (amino acids 105-686). In contrast, the amino-terminal region of the two proteins was markedly different (only 36% similarity), and human I beta cGK was 16 amino acids longer. In a specific region in the amino-terminus (amino acids 63-75), 12 out of 13 amino acids of the human I beta cGK were identical to the partial amino acid sequence recently published for a new I beta isoform of cGK from bovine aorta. Northern blot analysis demonstrated a human I beta cGK mRNA, 7 kb in size, in human uterus and weakly in placenta. An mRNA of 7 kb was also observed in rat cerebellum, cerebrum, lung, kidney, and adrenal, whereas an mRNA doublet of 7.5 and 6.5 kb were observed in rat heart. Comparison of Northern and Western blot analyses demonstrated that the mRNA and protein for cerebellar cGK increased during the development of rats from 5 to 30 days old, whereas the 6.5 kb mRNA in rat heart declined.
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PMID:Molecular cloning and predicted full-length amino acid sequence of the type I beta isozyme of cGMP-dependent protein kinase from human placenta. Tissue distribution and developmental changes in rat. 279 81

Cyclic guanosine 3',5' monophosphate (cGMP), cGMP-dependent protein kinase, calmodulin and cyclic adenosine 3',5' monophosphate (cAMP) were localized in the uterus of the immature rat by an indirect immunofluorescence technique. cGMP, cGMP-dependent protein kinase and calmodulin were detected predominantly along epithelial and myometrial plasma membranes and in the adjacent cytoplasm. In contrast, cAMP immunoreactive material was found principally in the cytoplasm of connective tissue. After administration of 17 beta-estradiol, similar time-dependent changes were observed in the localization of cGMP, cGMP-dependent protein kinase and calmodulin in all uterine cell types. For the three compounds, nucleolar-like distribution of the immunofluorescence appeared approximately 12 h after treatment. A more dispersed, reticular distribution of the nuclear fluorescent staining was observed 20-24 h after hormonal treatment. Estrogen did not affect the localization of cAMP. The simultaneous mobilization of cGMP, cGMP-dependent protein kinase and calmodulin towards the same nuclear loci suggests concerted roles for these three molecules in nuclear metabolic processes during the development of the uterotrophic action of estrogens.
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PMID:Immunofluorescent localization of cGMP, cGMP-dependent protein kinase, calmodulin and cAMP in the rat uterus. Effects of estrogen treatment. 631 98

Ultraviolet irradiation of human platelet cytosol in the presence of 32P-labelled cyclic GMP (cGMP) can specifically label 110, 80, 55, 49 and 38 kDa proteins; the 110 kDa species is the subunit of cGMP-inhibited phosphodiesterase (PDE III) and the 80 kDa species that of cGMP-dependent protein kinase (Tang et al., 1993, Biochem. J. 294, 329). We have now shown that although photolabelling of platelet PDE III was inhibited by unlabelled cGMP, 8-bromo-cGMP and cyclic AMP (cAMP), it was not affected by phosphorothioate analogues of these cyclic nucleotides. Specific concentration-dependent inhibitions of the photolabelling of PDE III were observed with the following PDE inhibitors: trequinsin (IC50 = 13 +/- 2 nM), lixazinone (IC50 = 22 +/- 4 nM), milrinone (IC50 = 56 +/- 12 nM), cilostamide (IC50 = 70 +/- 9 nM), siguazodan (IC50 = 117 +/- 29 nM) and 3-isobutyl 1-methylxanthine (IBMX) (IC50 = 3950 +/- 22 nM). Thus, measurements of the inhibitory effects of compounds on the photolabelling of platelet PDE III provide a simple quantitative means of investigating their actions at a molecular level that avoids the need to purify the enzyme. Photolabelling of rat platelet lysate or rat heart homogenate by [32P]cGMP showed that the 110 kDa PDE III present in human material was replaced by a 115 kDa protein, labelling of which was also blocked by PDE III inhibitors. Heart and other rat tissues contained much less of this putative 115 kDa PDE III than rat platelets. In contrast, the 80 kDa protein was labelled much less in platelets than in many other rat tissue homogenates (e.g., heart, aorta, uterus and lung). Thus, comparison of the relative amounts of specific photolabelled proteins in different cells may provide an indication of different patterns of cyclic nucleotide action. We compared the abilities of phosphodiesterase inhibitors to block the photolabelling of PDE III in human platelet cytosol and to increase the iloprost-stimulated accumulation of cAMP in intact platelets. Whereas trequinsin (EC50 = 19 +/- 3 nM), lixazinone (EC50 = 122 +/- 8 nM), milrinone (EC50 = 5320 +/- 970 nM) and siguazodan (EC50 = 18880 +/- 3110 nM) all increased platelet cAMP to the same maximum extent, cilostamide and IBMX increased cAMP further, indicating that they inhibited a PDE isozyme in addition to PDE III.
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PMID:Photoaffinity labelling of cyclic GMP-inhibited phosphodiesterase (PDE III) in human and rat platelets and rat tissues: effects of phosphodiesterase inhibitors. 792 8

The Na+/H+ exchangers belong to a family of transport proteins involved in intracellular pH regulation and vectorial sodium transport across various epithelial tissues. We have cloned a unique isoform (NHE-2) by screening a rat intestinal cDNA library utilizing a human NHE-1 fragment. In this report we describe molecular cloning of the human Na+/H+ exchanger (NHE-2, HGMW-approved symbol SLC9A2). The cDNA encodes a protein of 698 amino acid residues. Human NHE-2 is widely distributed in tissues of the gastrointestinal tract, kidney, heart, testes, uterus, and adrenal glands. Hydropathy plot indicates that the translated protein is predicted to have 10 transmembrane domains with three potential N-glycosylation sites and four potential cAMP- and cGMP-dependent protein kinase phosphorylation sites. This cDNA maps the location of the gene encoding NHE-2 to human chromosome 2q11.2.
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PMID:Molecular cloning, sequencing, chromosomal localization, and tissue distribution of the human Na+/H+ exchanger (SLC9A2). 859 99

The type I cGMP-dependent protein kinase (cGK) is one of the major pathways for the cGMP cascade and has been demonstrated to inhibit platelet aggregation, relax smooth muscle cells, and control cardiocyte contractility. There are two subtypes of the type I cGK, cGKIalpha and cGKIbeta. The former is more sensitive to cGMP than the latter. In humans, cGKIbeta cDNA was isolated, but the full structure and tissue-specific gene expression of cGKIalpha have not been determined. The significance of cGK in human cardiovascular diseases has not been investigated at the molecular level. In the present study, we isolated the full-length human CGKIalpha cDNA (-36 to +2177; the translation start site: +1) enclosing the 671-amino acid protein. Nucleotides +267 to +2177 of the isolated cDNA were identical to the corresponding nucleotides of human cGKIbeta cDNA. Southern blot analysis suggested that human cGKIalpha and cGKIbeta are generated by alternative splicing of a single gene assigned to chromosome 10. By Northern blot analysis, we detected abundant human cGKIalpha mRNA (7.0 kb) in the aorta, heart, kidneys, and adrenals. In contrast, human cGKIbeta mRNA (7.0 kb) was detected abundantly only in the uterus. In cultured vascular smooth muscle cells, the type I cGK mRNA concentration was reduced to 10% of the basal level by 4 x 10(-10) mol/L platelet-derived growth factor. Angiotensin II (10(-8) mol/L), transforming growth factor-beta (4 x 10(-11) mol/L), and tumor necrosis factor-alpha (6 x 10(-6) mol/L) also exhibited an inhibitory effect on type I cGK gene expression. These findings suggest a pathophysiological implication of the type I cGK in cardiovascular diseases, including hypertension and atherosclerosis.
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PMID:cDNA cloning and gene expression of human type Ialpha cGMP-dependent protein kinase. 861 2

1. There is conflicting evidence in the literature concerning the role of cyclic GMP in the regulation of myometrial contractility and the importance of hormonal status on the uterine response to cyclic GMP-elevating agents. The objective of the present study was to investigate further the importance of cyclic GMP in the control of uterine contractility, by monitoring the effects of cyclic GMP-elevating agents on spontaneous contractions and cyclic GMP levels in myometrial strips from pregnant rats and from ovariectomized rats under the influence of oestrogen and/or progesterone. 2. Sodium nitroprusside (SNP) 5 mM, atrial natriuretic peptide (ANP) 100 nM, L-arginine 1 mM and 8-bromo-cyclic GMP 100 mM had no relaxant effect on the spontaneous contractions of myometria from pregnant rats or from ovariectomized rats under the influence of oestrogen or progesterone. 3. Tissue levels of cyclic GMP were significantly elevated by SNP in all treatment groups, including pregnant animals. For example, in ovariectomized, progesterone-treated rats, SNP raised cyclic GMP levels approximately 8 fold from a basal level of 2.9 +/- 0.4 pmol mg(-1) protein to 24.8 +/- 4.0 pmol mg(-1) protein. ANP increased cyclic GMP levels approximately 2 fold in all treatment groups, except in the pregnant animals. L-Arginine elevated cyclic GMP significantly only in ovariectomized, vehicle-treated myometria. 4. The activity of cyclic GMP-dependent protein kinase (PKG) was significantly increased (3 fold) in myometria exposed to SNP (5 mM). Thus, the inability of SNP to relax uterine preparations was not due to a failure of SNP-elevated cyclic GMP to activate PKG. 5. The more potent NO donor, S-nitroso-N-acetylpenicillamine (SNAP), at a concentration of 100 microM was able to inhibit spontaneous contractions significantly in myometrial preparations from both non-ovariectomized and ovariectomized rats treated with oestrogen or progesterone. 6. Tissue levels of cyclic GMP were markedly increased by SNAP at concentrations of 10, 30 and 100 microM. At 100 microM, cyclic GMP levels increased from 1.9 +/- 0.2 pmol mg(-1) protein to 74.0 +/- 18.0 pmol mg(-1) protein. However, complete or partial blockade of SNAP-induced increases in cyclic GMP levels by the soluble guanylyl cyclase inhibitor, ODQ (25 microM), had no effect on the relaxant response to SNAP. Thus, the relaxant effect of SNAP in this tissue appears to be mediated via a mechanism independent of cyclic GMP. 7. Taken as a whole, the results of the present study indicate that cyclic GMP does not play an important role in the control of contractility in the rat uterus.
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PMID:Evidence that spontaneous contractile activity in the rat myometrium is not inhibited by NO-mediated increases in tissue levels of cyclic GMP. 953 26

Excessive or premature contractions of uterine smooth muscle may contribute to preterm labor. Contractile stimuli induce myosin and actin filament interactions through calcium-dependent myosin phosphorylation. The mechanisms that maintain myometrial quiescence until term are not well established, but may include control of calcium levels by nitric oxide and cGMP signaling and thin filament (caldesmon and calponin) regulation. Previously, we reported that myometrial tissues from pregnant rats are not responsive to cGMP due to decreases in cGMP-dependent protein kinase. Considering the well documented differences in the endocrinology of parturition among species, this study was conducted to test the hypothesis that the levels and subcellular distribution of caldesmon, calponin, and cGMP-dependent protein kinase are regulated with the hormonal milieu of human pregnancy. Whereas cGMP-dependent protein kinase was significantly reduced in the human uterus during pregnancy, caldesmon expression was significantly increased, and both caldesmon and calponin were redistributed to a readily extractable subcellular pool. These data suggest that cGMP-dependent protein kinase does not mediate gestational quiescence. Redistribution of thin filament-associated proteins, however, may alter uterine smooth muscle tone or the cytoskeletal framework of myocytes to maintain gestation despite the substantial distention that accompanies all intrauterine pregnancies.
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PMID:Reorganization of myofilament proteins and decreased cGMP-dependent protein kinase in the human uterus during pregnancy. 1150 42