Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P06889 (Mol)
 630,302 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A number of drugs which are known to affect lysosomes and their enzyme activities were used in an attempt to inhibit or delay the onset of denervation changes in rat muscles. The following parameters were used: the occurrence of fibrillations in electromyographs; diameters of muscle fibers; acid phosphatase activity; acetylcholinesterase activity and distribution in end plates. Differences between denervated and non-denervated limbs were evaluated and compared in the different treatment groups. The various parameters were differently affected by the different drugs. Chloroquin, thiouracil and streptomycin appeared to be more effective than other treatments in the inhibition of denervation changes.
Cell Mol Biol 1989
PMID:An attempt to prevent or delay denervation changes in rat muscles. 273 Nov 90

To evaluate the possible role of intracellular phosphatases in the local regulation of prostatic functions, the effect of sodium orthovanadate (VO4), an inhibitor of phosphotyrosyl protein phosphatases, was studied on both protein phosphorylation and acid phosphatase activity. Secretory and non-secretory epithelial cells were isolated from normal and metaplastic prostates and incubated with [32P]phosphate in the presence and in the absence of VO4; the phosphoproteins were separated by electrophoresis and the gels were either directly submitted to autoradiography or after an alkali treatment to reveal those proteins enriched in phosphotyrosine. Prior to alkali treatment, several phosphoproteins were evidenced and in less than half of the cell preparations a slight increase in labeling intensity under vanadate (less than 75%) was observed in two phosphoproteins, p57 and p44. After alkali treatment: (1) the effect of VO4 on p57 remained in the order of 44-45% and it was restricted to less than half of non-secretory cell preparations; (2) its effect on p44 was intensified (134-207%) and observed in all cell types and in more than 80% of all preparations; and (3) in half of non-secretory cell preparations from metaplastic glands, an effect of VO4 on p35 (127%) became evident. In all instances, with normal and/or metaplastic prostates, protein phosphorylation activity, either total or alkali-resistant and in the presence or in the absence of VO4, was always higher in non-secretory epithelial cells as compared to secretory cells.(ABSTRACT TRUNCATED AT 250 WORDS)
Mol Cell Endocrinol 1989 Jun
PMID:Effect of vanadate on protein phosphorylation and on acid phosphatase activity in the canine prostate. 275 42

Lysosomes are defined traditionally with the marker enzyme acid phosphatase. We showed recently that lysosomes from human fibroblasts can be separated into a light and dense fraction as well as prelysosomal population. We now provide evidence that although acid phosphatase is enriched in all three fractions, the marker enzyme in the prelysosomal compartment is qualitatively distinct from that of the lysosomes. Ultrastructural analysis showed that the acid phosphatase in the prelysosomal vesicles deposited an extremely electron-dense reaction product, entirely obliterating the lumen of the vesicle, in contrast to that of the light and dense lysosomes which deposited a fine and diffuse product scattered throughout the luminal space. Biochemical analysis showed that only 51% of the acid phosphatase in the prelysosomes was inhibited by tartrate, while 80% of that in the lysosomes was tartrate-inhibitable. Immunoprecipitation with antibodies specific for various isozymes of acid phosphatase showed that 39% of the acid phosphatase in the prelysosomes was of the 'lysosomal' type whereas over 50% of the acid phosphatase in the lysosomes was of this type. These results showed that acid phosphatase in the prelysosomes of human cultured fibroblasts can be distinguished from that of the lysosomes cytochemically, biochemically, and immunologically and that lysosomes, as marked by acid phosphatase, are a heterogeneous organelle.
Mol Cell Biochem 1989 Jun 01
PMID:Heterogeneity of lysosomes in human fibroblasts. 277 Jul 20

The level of resistance to infection in inbred mice with the murine malaria species Plasmodium chabaudi AS is genetically determined. Resistant C57BL/6, which are able to eliminate the parasite by 4 weeks, develop marked splenomegaly and survive the infection. Susceptible A/J mice, which succumb to infection (mean survival time = 10 days), develop only minimal splenomegaly. In order to determine if gross differences in the organization, number, and type of spleen cells are related to the outcome of infection with P. chabaudi AS, the development of splenomegaly was examined by enzyme and immunohistochemical methods during the first week after infection. Cryostat sections of spleens removed from normal animals of both strains and at 4 and 7 days after intraperitoneal infection with 10(6) parasitized erythrocytes were stained for enzyme (acid phosphatase and nonspecific esterase) and immunohistochemistry with conventional monoclonal antibodies against T cells, B cells, and macrophages as well as with novel rat anti-mouse monoclonal antibodies which define discrete subpopulations of macrophages in the mouse spleen. The livers of normal and infected animals of each strain were also examined. The results of this study demonstrate (1) differences between normal, uninfected B6 and A/J mice in the organization and number of one subpopulation of macrophages in the spleen, the marginal metallophilic macrophages, and (2) marked histological changes in the spleen and liver during the course of infection in both resistant C57BL/6 and susceptible A/J mice. These changes include depletion of cells from the marginal zone of the spleen which, in the case of the marginal metallophilic macrophages, appears to be more severe in susceptible A/J mice.
Exp Mol Pathol 1989 Aug
PMID:Histological changes in the spleen and liver of C57BL/6 and A/J mice during Plasmodium chabaudi AS infection. 278 81

The hepatic transport mechanism for the fluorescent bivalent hydrophilic organic cation lucigenin (LU) was characterized employing kinetic and morphological methods. The extraction of LU by the perfused rat liver was 50% and uptake was saturable. LU did not inhibit the carrier-mediated hepatic uptake of the model organic cationic compounds tributylmethyl ammonium (type 1) and vecuronium (type 2) in isolated hepatocytes, whereas the uptake of LU in the perfused liver was not affected by either type of cation or by the cardiac glycoside cymarin, a potent type 2 inhibitor. The cytoskeleton-disrupting agents cytochalasin B and nocodazole, however, significantly lowered hepatic uptake of LU. In the intact liver, LU did not stimulate fluid phase endocytosis, as indicated by a lack of effect on the internalization of horseradish peroxidase. These kinetic data point to adsorptive endocytosis as the most probable uptake mechanism. This was confirmed by the inhibitory effect of neomycin and the polycation poly(L-lysine) on LU uptake. Fluorescence microscopy revealed that LU accumulated in the hepatocytes in discrete vesicular structures. Partial co-localization of rhodamine-dextran and acid phosphatase with LU indicated that part of the LU fluorescence was present in lysosomes, although not all lysosomes contained LU. Taken together, we conclude that we identified a novel vesicular pathway for uptake of organic cations by hepatocytes.
Mol Pharmacol 1989 Oct
PMID:Vesicular uptake system for the cation lucigenin in the rat hepatocyte. 281 56

The structural gene for an acid phosphatase coded for by the gene appA of Escherichia coli K12 was cloned from a cosmid library into pBR322 and the restriction map determined. Several appA deletion plasmids and a smaller appA+ plasmid were constructed by in vitro recombination techniques and tested for their ability to complement an appA1 mutation. The appA gene was localized within a 2.1 kb segment. Its orientation was determined by construction of a hybrid plasmid carrying an appA-lacZ fusion. beta-galactosidase synthesized from the appA promoter was negatively regulated by cyclic AMP.
Mol Gen Genet 1987 Jul
PMID:Cloning and characterization of the pH 2.5 acid phosphatase gene, appA: cyclic AMP mediated negative regulation. 282 63

1. We performed an enzymatic characterization of two different fractionation procedures of ventricles from rat hearts. The enzymatic assays covered succinic dehydrogenase as a marker for inner mitochondrial membranes, monoamine oxidase as a marker for outer mitochondrial membranes, NADPH-cytochrome c reductase and RNA as endoplasmatic reticular markers, acid phosphatase as a lysosomal marker, and lactic dehydrogenase as a marker for the "soluble" compartment; DNA was estimated for nuclear contamination. 2. The plasma membrane markers 5'-nucleotidase, Ca2+-ATPase, Mg2+-ATPase, Na+-K+-ATPase, and adenylate cyclase were determined. 3. The roughly prepared membrane fractions showed increased yields of the membrane markers; the number of beta receptors, determined with (-)-[3H] dihydroalprenolol and DL-propranolol, amounted to 68 +/- 6 fmol/mg protein (KD = 3390 +/- 450 pmol, Hill coefficient = 1.5). 4. The membrane fraction prepared with a linear sucrose gradient showed an increased inner mitochondrial membrane marker; presumably the outer mitochondrial membrane was stripped off. The beta-receptor number was 39 +/- 3 fmol/mg protein (KD = 6250 +/- 300 pmol; Hill coefficient = 1.2).
Cell Mol Neurobiol 1988 Jun
PMID:Beta-adrenergic receptors and enzymes in rat myocardial membranes: implications of fractionation procedures and beta-adrenoceptor antagonists. 284 52

Highly purified preparations of plasma membranes from control and ketoconazole-treated (1 microM, 120 h) epimastigotes of Trypanosoma cruzi have been obtained by cell disruption using abrasion with glass beads, differential centrifugation and isopycnic centrifugation in continuous, self-generating Percoll gradients. The purity of the preparation was ascertained by the specific activity 125I bound to the membranes obtained from enzymatically radiolabeled epimastigotes and by the alpha-methyl-mannoside sensitive binding of 125I-concanavalin A. The membranes form closed vesicles of 0.2-0.4 micron in diameter which display Mg2+ ATPase and acid phosphatase activities, but are devoid of 5'-nucleotidase and succinate-cytochrome c oxidoreductase; these vesicles can be strongly agglutinated by concanavalin A. The lipid order profiles of membranes from control and treated cells were compared with that present in egg phosphatidylcholine/ergosterol liposomes (84:16, mol/mol) by electron spin resonance spectroscopy of doxylstearic acid probes with the nitroxide group bound to carbon 5, 10, 12 and 16 of the stearic acid chain. Membranes from treated epimastigotes have a lipid order profile which resembles that of control plasma membranes near the polar surface (positions 5 and 10) but there is an abrupt decrease of order at position 12 and from there to the center of bilayer is highly disordered, even more than in pure lipid membranes. Consistent with these results, the leakage of L-[14C]glucose from membrane vesicles of ketoconazole-treated cells is much faster than that observed in vesicles obtained from control cells. These results indicate a strong alteration of the plasma membrane physical and biological properties due to the incubation of the parasite with the drug; this alteration is consistent with the accumulation of methylated precursors of ergosterol, which affects both lipid-lipid and lipid-protein interactions in the membrane.
Mol Biochem Parasitol 1988 Aug
PMID:Alteration of lipid order profile and permeability of plasma membranes from Trypanosoma cruzi epimastigotes grown in the presence of ketoconazole. 284 68

Human prostatic acid phosphatase (PAcP) has been found to have phosphotyrosyl-protein phosphatase activity (H. C. Li, J. Chernoff, L. B. Chen, and A. Kirschonbaun, Eur. J. Biochem. 138:45-51, 1984; M.-F. Lin and G. M. Clinton, Biochem. J. 235:351-357, 1986) and has been suggested to negatively regulate phosphotyrosine levels, at least in part, by inhibition of tyrosine protein kinase activity (M.-F. Lin and G. M. Clinton, Adv. Protein Phosphatases 4:199-228, 1987; M.-F. Lin, C. L. Lee, and G. M. Clinton, Mol. Cell. Biol. 6:4753-4757, 1986). We investigated the molecular interaction of PAcP with a specific tyrosine kinase, the epidermal growth factor (EGF) receptor, from prostate carcinoma cells. Of several proteins phosphorylated in membrane vesicles from prostate carcinoma cells, PAcP selectively dephosphorylated the EGF receptor. The prostate EGF receptor was more efficiently dephosphorylated by PAcP than by another phosphotyrosyl phosphatase, potato acid phosphatase. Further characterization of the interaction of PAcP with the EGF receptor revealed that the optimal rate of dephosphorylation occurred at neutral rather than at acid pH. Thus, the enzyme that we formerly referred to as PAcP we now call prostatic phosphotyrosyl-protein phosphatase. Hydrolysis of phosphate from tyrosine residues in the immunoprecipitated EGF receptor catalyzed by purified prostatic phosphotyrosyl-protein phosphatase caused a 40 to 50% decrease in the receptor tyrosine kinase activity with angiotensin as the substrate. In contrast, autophosphorylation of the receptor was associated with an increase in tyrosine kinase activity.
Mol Cell Biol 1988 Dec
PMID:The epidermal growth factor receptor from prostate cells is dephosphorylated by a prostate-specific phosphotyrosyl phosphatase. 285 98

Fine structural aspects of the effect of minocycline, an antibiotic of the tetracycline group, on the rat thyroid were studied. In all the rats administered minocycline (100 mg/kg/day) for 21 days, diffuse black discoloration of the thyroid gland occurred. However, when the rats were fed on a low iodine diet, given propylthiouracil (PTU) or thyroxine tablet with minocycline the black pigmentation of the thyroid gland did not take place. On the other hand, black discoloration of the thyroid was accelerated in the rats administered TSH and minocycline simultaneously. Ultrastructurally, numerous dense bodies containing highly electron-dense deposits were seen in the supranuclear region of the follicular epithelial cells of the black thyroid. These dense bodies, which showed positive acid phosphatase activity, are considered to be lysosomes containing minocycline or its derivatives. It is speculated that minocycline is taken up into follicular epithelial cells with iodine, and that the black discoloration of the thyroid gland is intimately related to iodine metabolism.
Virchows Arch B Cell Pathol Incl Mol Pathol 1985
PMID:Fine structural aspects of the black thyroid induced by minocycline, and the effects of a low iodine diet, propylthiouracil, thyroxine tablet and TSH, on the black discoloration of the rat thyroid. 285 95


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