Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.4.1 (phosphodiesterase)
 18,767 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The literature on tumor distinctive markers in ovarian cancer has been reviewed. Various immunological and biochemical approaches have been attempted for the diagnosis and management of patients with ovarian cancer. The complex spectrum of antigens that can be detected in human ovarian cancer consists of several tumor-associated antigens, fetal or carcinoembryonic antigens, carcinoplacental markers, and normal tissue antigens. We have described and partially characterized two ovarian tumor-associated antigens designated as OCAA and OCAA-1, which seem to have potential for the immunodiagnosis of ovarian cancer. Several other investigators have carried out similar studies, but in general their serological characterization of these antigens has been limited. The well-defined embryonic proteins that have been examined in the ovarian cancer include carcinoembryonic antigen (CEA), alpha-fetoprotein (alpha-fp), beta-oncofetal antigen (BOFA), Regan and Nagao isoenzymes and human chorionic gonadotropin (HCG). The presence of pregnancy-zone protein (PZP) has also been reported in ovarian cancer. In addition, several normal tissue components include fibrin-fibrinogen degradation products (FDP), alpha 1-globulin, and urokinase have been found associated with ovarian cancer. Both humoral antibodies and cell-mediated immune responses against tumor-associated antigens can be measured in ovarian cancer patients. In addition, serum factors, which block cellular immune reactions, have been identified. However, progress in this area has been hampered by the complexity of the antigens associated with ovarian tumors and the lack of standardized, well-characterized sources of antigens or target cells. Enzymes, especially those involved in glycoprotein biosynthesis, (eg, glycoprotein:glycosyltransferases and glycosidase) have been explored as possible early biochemical indicators of ovarian neoplasia. A serum specific deficiency of alpha-L-fucosidase has been found in patients with ovarian cancers. Of all the glycoprotein:glycosyltransferases studied, galactosyltransferase has been found to be the best enzyme marker for ovarian adenocarcinoma. The determination of serum levels of this enzyme reflected the clinical status of the patient with respect of tumor progression as well as tumor burden. Recently, assay of a phosphodiesterase, which specifically hydrolyzes cytidine 5'-monophospho-N-acetylneuraminic acid, has been found promising in the detection and management of patients with ovarian cancer.
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PMID:Tumor markers for ovarian cancer. 9 53

The levels of GPC phosphocholine phosphodiesterase, pNP phosphocholine phosphodiesterase, CNPase, and UDP galactose: ceramide galactosyltransferase activities were estimated with pure cultures of oligodendrocytes and astrocytes; mixed primary glial cells cultures; C-6 cells; and CNS tissue of the dysmyelinating md rat, the jimpy mouse, and the quaking mouse. The highest activity of GPC and pNP phosphocholine phosphodiesterases as with CNPase and C gal T was found in the pure cultured oligodendrocytes. C-6 cells had very low or undetectable activities for these two phosphodiesterases but possessed very high CNPase activity. The activity of GPC phosphocholine phosphodiesterase was significantly decreased in the CNS tissue of the md rat and the jimpy and the quaking mouse. Similar reductions were observed for the pNP phosphocholine phosphodiesterase, CNPase, and C gal T activities. The selective cellular enrichment in oligodendrocytes of the GPC phosphocholine phosphodiesterase activity and decreases of its activity in three dysmyelinating mutants in the same ratio as for CNPase and C gal T suggest that GPC phosphocholine phosphodiesterase is a myelin marker enzyme and it may reflect the quantity of myelin and oligodendrocyte present.
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PMID:Glycerophosphorylcholine phosphocholine phosphodiesterase activity in cultured oligodendrocytes, astrocytes, and central nervous tissue of dysmyelinating rodent mutants. 131 6

A new Ca2+/calmodulin-dependent serine kinase was isolated from rat parotid gland acinar cells following chronic treatment with the beta-agonist isoproterenol. A single-step purification was performed on a calmodulin-agarose affinity column, following solubilization with Triton X-100. Among various substrates tested, bovine galactosyltransferase was the preferred substrate of the kinase, followed by glycogen synthetase greater than histone greater than phosphodiesterase greater than phenylalanine hydroxylase greater than phosphorylase b greater than bovine serum albumin. In comparison, a spleen preparation of Ca2+/calmodulin-dependent kinase did not show galactosyltransferase to be the preferred substrate. Thus, the enzyme would appear to be similar to the human galactosyltransferase-associated kinase. The kinase activity was saturable with 100 microM Ca2+ and 2 microM calmodulin. The molecular mass determined by nondenaturing and sodium dodecyl sulfate polyacrylamide gel electrophoreses was 75 kDa with a pI of 4.3. The Vmax was 3500 mumol/(min.mg protein) with a Km of 1.6 microM for the transferase substrate. Leukotriene C and prostaglandin E2 were found to be specific noncompetitive inhibitors of the rat galactosyltransferase-associated kinase.
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PMID:Isolation and characterization of a new Ca2+/calmodulin-dependent protein kinase from isoproterenol-stimulated proliferating rat parotid acinar cells. 138 38

Previous studies from this laboratory and others have identified several enzymes on the surface of mammalian spermatozoa. Some of these enzymes, namely a galactosyltransferase and a novel alpha-D-mannosidase, are believed to play a ligand-like role in recognizing and binding to the complementary moiety(ies) present on zona pellucida glycoconjugates. However, little or no information is available about the occurrence of these enzymes in human spermatozoa. In the present report, we show that a very small amount of the total galactosyltransferase activity present in human semen is associated with spermatozoa. Moreover, our failure to find a significant amount of the enzyme on sperm plasma membranes suggests that the enzyme is not associated with the sperm surface. Therefore, it is unlikely that galactosyltransferase in humans has the same ligand-like role in zona binding that is demonstrated in mouse sperm. In contrast, nearly 5% of alpha-D-mannosidase activity was repeatedly found in the salt-washed plasma membrane fraction. The recovery and enrichment of the alpha-D-mannosidase was nearly one-half that observed for adenylate cyclase and nearly one-third that for phosphodiesterase I, the two sperm plasma membrane marker enzymes. The differential enrichment and recovery of the sperm surface alpha-D-mannosidase is consistant with our previous studies in rat spermatozoa, and suggests that alpha-D-mannosidase may be localized on morphologically distinct region(s) of the sperm plasma membranes. The properties of human sperm surface alpha-D-mannosidase are quite similar to those reported by us for rat sperm plasma membrane mannosidase, but quite different from human sperm acid alpha-D-mannosidase. In addition, whereas anti-rat epididymal alpha-D-mannosidase antibody (IgG-fraction) cross-reacted with the human sperm acid alpha-D-mannosidase, no cross-reactivity was observed with the sperm surface mannosidase. A small amount of fucosyltransferase (less than 1% of the enzyme originally present on spermatozoa) was found in the salt-washed plasma membrane, but the enrichment of the enzyme was only one-tenth of that observed for adenylate cyclase. The potential ligand-like role of human sperm surface alpha-D-mannosidase and other sperm surface enzymes during fertilization is discussed.
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PMID:Human sperm plasma membranes possess alpha-D-mannosidase activity but no galactosyltransferase activity. 211 23

Chronic administration of the beta-adrenergic receptor agonist isoproterenol (5 mg/200 g animal for 10 days) resulted in rat parotid and submandibular gland hypertrophy, and it induced synthesis of a series of proline-rich proteins (PRPs) and glycoproteins. Treated parotid glands additionally exhibit an increase in activity for the Golgi membrane enzyme UDP-galactose; N-acetylglucosamine 4 beta-galactosyltransferase. A series of beta-receptor agonists and phosphodiesterase inhibitors were examined for their abilities to influence salivary gland protein biosynthesis in a fashion similar to that observed with chronic isoproterenol treatment. beta 1/beta 2-Adrenergic-receptor agonists exhibited the greatest effects on parotid gland hypertrophy and PRP biosynthesis. These beta-agonists were also able to increase 4 beta-galactosyltransferase activity, but they did not promote the synthesis of a 220,000 dalton glycoprotein. Terbutaline (beta 2-receptor agonist) induced parotid gland hypertrophy but was only able to induce protein biosynthesis at higher drug concentrations. Finally, methoxyphenamine was unable to produce the observed changes in protein synthesis even at increased drug dosages. The phosphodiesterase inhibitors (theophylline and caffeine) were able to induce de novo PRP biosynthesis at drug doses of 20 mg/200 g animal. However, while causing mild gland hypertrophy, there was no observable change in 4 beta-galactosyltransferase activity with either phosphodiesterase inhibitor. This same regimen of beta-receptor agonists was unable to induce submandibular gland hypertrophy, PRP or glycoprotein biosynthesis in the same animals. This was also true for the two phosphodiesterase inhibitors. Co-injection of a beta 1 antagonist along with isoproterenol blocked the above protein changes in both the submandibular and parotid glands, suggesting that the stimulation of protein synthesis takes place by beta 1-type receptors on the gland cell surfaces.
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PMID:Analysis of protein synthesis in rat salivary glands after chronic treatment with beta-receptor agonists and phosphodiesterase inhibitors. 286 70

Three populations of pure coated vesicles from adrenocortical cells, differing in their density, i.e., 1.125-1.155, 1.155-1.175, and 1.175-1.210 g/cm3, are obtained after separation on two successive sucrose-2H2O gradients. They are involved in LDL internalization and in the receptor cycle as confirmed by the presence, in each population, of the LDL receptor. Electron micrographs confirm the existence of three homogeneous populations exhibiting the typical polygonal structure of the clathrin coat. They differ in their size distribution (small, congruent to 70-nm diameter; medium, congruent to 90-nm diameter; large, congruent to 110-nm diameter) and in the organization of clathrin and of the coat proteins as evidenced on electrophoreses carried out under nondenaturing and denaturing conditions. Activity measurements of marker enzymes, phosphodiesterase and galactosyltransferase, suggest that medium coated vesicles might originate from plasma membranes and small ones from the Golgi complex. Large coated vesicles exhibit phosphokinase enzyme and substrate polypeptides different from those of the two other populations, tubulins being the preferred kinase substrates for the small and medium coated vesicles. These kinases are autophosphorylating enzymes and are revealed, by nondenaturing electrophoreses, as different high molecular mass complexes in the three populations. Clathrin and coat proteins are not part of these complexes.
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PMID:Biochemical and functional characterization of three types of coated vesicles in bovine adrenocortical cells: implication in the intracellular traffic. 290 76

Purified secondary cultures of mouse Schwann cells (less than 5% fibroblast contamination) have been obtained by taking advantage of the differential adhesion of Schwann cells and fibroblasts during trypsinization. The growth properties of the purified subcultures changed with time in culture. Cells passaged after 5 days in vitro (DIV) divided rapidly (doubling time 22 h), whereas cells that had been in vitro for longer periods progressively decreased their growth rate, becoming quiescent after 20 or more days. Schwann cells lacked the Thy 1.2 surface antigen, but were positively stained with antigalactocerebroside antibodies after prefixation. Biochemical analyses showed Schwann cells to be enriched in the activities of enzymes characteristic of the myelin-forming cells: 2'3'-cyclic nucleotide 3'-phosphodiesterase (CNP), cerebroside sulfotransferase (CST) and UDP-galactose: ceramide galactosyltransferase (CGalT).
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PMID:Growth properties and biochemical characterization of mouse Schwann cells cultured in vitro. 631 7

Lymph node cell homogenates were fractionated by differential or isopycnic centrifugation and the fractions analyzed for biochemical markers with particular focus on plasma membrane constituents. Markers for the nucleus (DNA), mitochondria (cytochrome oxidase), and lysosomes (acid hydrolases) showed the expected distributions which were different from those of membrane-bound enzymes. 5'-Nucleotidase, alkaline phosphodiesterase, gamma-glutamyltranspeptidase, and cholesterol were membrane-bound and distributed identically after isopycnic centrifugation with peaks at 1.15. The distributions of the enzymes were all shifted to higher densities by digitonin treatment, confirming their association with plasma membrane-derived elements. The distribution of galactosyltransferase (ovalbumin acceptor), largely overlapped those of plasma membrane markers but it was only slightly shifted by digitonin, suggesting its localization in Golgi apparatus. The distribution of mannosyltransferase (dolichyl phosphate acceptor) also overlapped those of plasma membrane and Golgi markers but it was centered at higher density (1.18) and was unaffected by digitonin. It is a useful marker for endoplasmic reticulum. 50% of the activity was in low speed "nuclear" sediments where it was associated with the nuclear membrane. A number of other putative and previously used markers for the endoplasmic reticulum of lymphocytes were shown not to be localized in these membranes. In particular, NADH-cytochrome c reductase was only partly associated with the endoplasmic reticulum (56%) and the remainder of the activity was in mitochondria (44%). The results show the heterogeneity in equilibrium density of plasma membrane vesicles and the considerable overlap of their distribution with those of other cellular membranes; they should provide a basis for the more rational design of preparative procedures for the lymphocyte plasma membrane.
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PMID:Characterization of rat lymphocyte cell membranes by analytical isopycnic centrifugation. 660 29

A method for the subcellular fractionation of rat liver using whole homogenates of rat liver and analytical sucrose density gradient centrifugation is presented. The distributions in the sucrose gradients of marker enzymes for all organelles have been determined for control homogenates and for homogenates prepared in the presence of selective membrane perturbants. This technique is not subject to potential loss of information inherent in the use of postnuclear supernatants as starting material for fractionation experiments. Particular attention has been paid to the distributions of putative plasma membrane marker enzymes, up to 50% of which may be found in the nuclear pellet. Gamma-Glutamyltransferase has been found to be entirely plasma membrane in location but has a different distribution pattern when compared with other plasma membrane markers. Particulate alkaline phosphatase and alkaline phosphodiesterase are shown to have bimodal distribution, one peak of which is coincident with 5'-nucleotidase. The other peak is coincident with that of the golgi marker, galactosyltransferase, but the membrane structure containing these activities shows characteristics of plasma membrane rather than golgi apparatus.
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PMID:Analytical subcellular fractionation of rat liver with special reference to the localisation of putative plasma membrane marker enzymes. 737 35

WI-38 fibroblasts cultivated in vitro were homogenized and their subcellular organelles analysed by the techniques of differential centrifugation and isopycnic equilibration in density gradient. In these experiments, the assayed enzymes were known to be specifically associated with subcellular components in other cells types. In most cases, their behaviour and properties corresponded with observations made in earlier studies and we could consider them as being representative of the specific subcellular organelles. Some significant differences were observed between young and old fibroblasts. The specific activity of alkaline phosphodiesterase was lower in the old cells whereas for the other enzymes it was identical or higher, especially for the 5'-nucleotidase; also the particulate fractions obtained by differential centrifugation contained more material. After equilibration in density gradient, the average density of the 5'-nucleotidase, alkaline phosphodiesterase and N-acetyl-beta-D-glucosaminidase was less in the old than in the young cells, whereas that of the galactosyltransferase of Golgi apparatus was greater. For mitochondria, endoplasmic reticulum and peroxisomes, the differences observed were small.
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PMID:Subcellular fractionation of WI-38 fibroblasts. Comparison between young and old cells. 738 46


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