Properties and Expression of an ATP-Degrading Ectoenzyme Cascade on Human Lymphoid Cells

Gutensohn, Wolf; Rieger, Juliane

doi:10.1007/978-3-642-70664-6_6

Cited by 8 publications

(5 citation statements)

References 17 publications

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“…e. Most studies performed to date leave open the question of the final hydrolysis product of ATP or the nucleoside triphosphate. However, in accordance with our results, it has been shown for vascular endothelial cells (Pearson et al, 1980) and lymphoid cells (Gutensohn and Rieger, 1986) that, besides nucleoside triphosphates, nucleoside diphosphates and nucleoside monophosphates can also become hydrolyzed by ectoenzyme activities, yielding the nucleoside as the final hydrolysis product. In other cases, at least parallel association of ecto-NTPase and ecto-5'-nucleotidase activity has been demonstrated: in polymorphonuclear leukocytes (DePierre and Karnovsky, 19744, mammary gland tumor cells (Carraway et al, 19801, and lymphoid cells (Dornand et al, 1986).…”

Section: Inhibition Of Atp Hydrolysissupporting

confidence: 92%

“…This includes studies on nerve endings from brain (Lin and Way, 1982;Nagy, 1986), neuroblastoma and glial cells (Stefanovich e t a l . , 1976), human blood platelets (Chambers et al, 1967), lymphoid cells (Gutensohn and Rieger, 1986), or skeletal muscle cells (Manery et al, 1984) and is in full accordance with our re-sults on cholinergic synaptosomes of Torpedo. The enzyme activity observed in these studies, therefore, has to be addressed as a nucleoside triphosphate phosphohydrolase (NTPase) rather than as an ATPase.…”

Section: Inhibition Of Atp Hydrolysissupporting

confidence: 88%

“…Although the exocytotic release of ATP together with ACh at the cholinergic electromotor nerve terminal implies a specific involvement of the NTPase activity observed in the process of synaptic signal transmission, it appears of interest that ecto-NTPase or ecto-ATPase activity has been described for a variety of cell types. Besides nerve cells, these inclufle Ehrlich ascites carcinoma cells (Ronquist and Agren, 1975), blood platelets (Chambers et al, 1967), guinea pig polymorphonuclear lymphocytes (DePierre and Karnovsky, 1974a,b), granulocytes (Smolen and Weissman, 1978), human lymphoid cells (Dornand et al, 1986;Gutensohn and Rieger, 1986), epididymal spermatozoa (Majumder, 1981), vascular endothelial cells and smooth muscles cells in culture (Pearson et al, 1980), mammary tumor cells (Carraway et al, 1980), neuroblastoma and glial cells in culture (Stefanovich et al, 1976), and also isolated pancreas cells (Hamlyn and Senior, 1983) and skeletal muscle cells (Manery et al, 1984). It has been suggested (Trams and Lauter, 1974) that ecto-ATPase activity may be a property of all cell surfaces.…”

Section: Inhibition Of Atp Hydrolysismentioning

confidence: 99%

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Ectonucleotidase Activities Associated with Cholinergic Synaptosomes Isolated from Torpedo Electric Organ

Grondal¹,

Zimmermann²

1986

Journal of Neurochemistry

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Intact synaptosomes isolated from the electric organ of the electric ray Torpedo marmorata contain, at their surface, enzyme activities for the hydrolysis of externally applied nucleoside phosphates. The diazonium salt of sulfanilic acid, as a low‐molecular‐weight, slowly permeating, covalent inhibitory agent, selectively blocks these enzyme activities and leaves intracellular lactate dehydrogenase intact. The ectoenzymes comprise both a nucleoside triphosphate and diphosphate phosphohydrolase, as well as a 5′‐nucleotidase. Activity of nonspecific ectophosphatases is absent. The nucleoside triphosphatase hydrolyzes almost equally well ATP, GTP, CTP, UTP, and ITP and is activated to a similar degree by Mg2+ or Ca2+. It has a high affinity for ATP (Km for ATP in the presence of Mg2+, 75 μM; in the presence of Ca2+, 66 μM). Maximal rates in the presence of Mg2+ and Ca2+ were very similar (34.8 and 32.5 nmol of P/min/mg of synaptosomal protein, respectively). Either Mg‐ATP or Ca‐ATP can act as a true substrate. ADP inhibits hydrolysis of ATP, but AMP is without effect. The nucleoside triphosphatase is not inhibited significantly by a number of inhibitors of mitochondrial Mg2+‐ATPase or of Ca2++ Mg2+‐ATPases. It is, however, considerably inhibited by filipin and quercitin. The capacity of intact synaptosomes to hydrolyze also extracellular ADP, GDP, AMP, GMP, and IMP suggests that the nucleoside triphosphatase is part of an enzyme chain that causes complete hydrolysis of the respective nucleoside triphosphate to the nucleoside. We conclude that the cholinergic nerve terminals of the Torpedo electric organ can hydrolyze ATP released on coexocytosis with acetylcholine via an ectonucleoside triphosphatase activity that is different from known endogenous nerve terminal ATPases. The final product of the hydrolysis, adenosine, can then be salvaged by the nerve terminal for resynthesis of ATP. Other possible physiological functions of the ectonucleotidases are discussed.

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Section: Inhibition Of Atp Hydrolysissupporting

confidence: 92%

Section: Inhibition Of Atp Hydrolysissupporting

confidence: 88%

Section: Inhibition Of Atp Hydrolysismentioning

confidence: 99%

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Ectonucleotidase Activities Associated with Cholinergic Synaptosomes Isolated from Torpedo Electric Organ

Grondal¹,

Zimmermann²

1986

Journal of Neurochemistry

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“…The nucleoside diphosphokinase activity shown in Fig. 3 has not been characterized, although similar enzymes have been shown to be present on vascular endothelial cells (Pearson et al, 1980) and lymphoid cell lines (Gutensohn and Rieger, 1986). The role of such an enzyme is unclear, although it may be asso- ciated with ATP degradation in the presence ofnonadenine dinucleotides.…”

Section: The Ectonucleotidase Enzymesmentioning

confidence: 99%

“…However, in some systems, adenosine produced from released ATP may subsequently modulate cell function via P, purinoreceptors (Ribeiro and Sebastiao, 1987;. The best characterized ectonucleotidase pathways are in peripheral systems, e.g., lymphoid cells (Gutensohn and Rieger, 1986), vascular endothelial cells (Pearson et al, 1980;Gordon et al, 1986;Slakey et al, 1986), the frog neuromuscular junction (Cunha and Sebastiao,199 I), and the Torpedo electromotor synapse (Grondal and Zimmermann, 1986). As far as the CNS is concerned, ecto-ATPase activities have been studied in cultured cells (Stefanovic et al, 1976), astrocytes (Lai and Wong,199 l), and heterogenous nerve terminals (Nagy et al, 1986).…”

mentioning

confidence: 99%

Production of Adenosine from Extracellular ATP at the Striatal Cholinergic Synapse

James

Richardson

1993

Journal of Neurochemistry

158

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The components of the ectonucleotidase pathway at the immunoaffinity-purified striatal cholinergic synapse have been studied. The ecto-ATPase (EC 3.6.1.15) had a Km of 131 microM, whereas the ecto-ADPase (EC 3.6.1.6) had a Km of 58 microM, was Ca(2+)-dependent, and was inhibited by the ATP analogue 5'-adenylylimidodiphosphate (AMPPNP). The ecto-5'-nucleotidase (EC 3.1.3.5) had a Km of 21 microM, was inhibited by AMPPNP and alpha,beta-methylene ADP, and by a specific antiserum. The Vmax values of the ATPase, ADPase, and 5'-nucleotidase enzymes present at this synapse were in a ratio of 30:14:1. Very little ecto-adenylate kinase activity was detected on these purified synapses. The intraterminal 5'-nucleotidase enzyme, which amounted to 40% of the total 5'-nucleotidase activity, was inhibited by AMPPNP, alpha,beta-methylene ADP, and the antiserum, and also had the same kinetic properties as the ectoenzyme. The time course of ATP degradation to adenosine outside the nerve terminals showed a delay, followed by a period of sustained adenosine production. The delay in adenosine production was proportional to the initial ATP concentration, was a consequence of feedforward inhibition of the ADPase and 5'-nucleotidase, and was inversely proportional to the ecto-5'-nucleotidase activity. The function and characteristics of this pathway and the central role of 5'-nucleotidase in the regulation of extraterminal adenosine concentrations are discussed.

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Qualitative and quantitative differences between Burkitt lymphoma and lymphoblastoid cell lines in the expression of membrane ecto‐nucleotidases and in the response to agonists of the A₂‐type adenosine receptor

Gutensohn¹,

Jahn²

1988

Intl Journal of Cancer

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The activity of ecto-nucleotidases has been determined on intact cells from Burkitt lymphoma (BL) and lymphoblastoid cell lines established in vitro (LCLs). BL cells never express ecto-5'-nucleotidase (5'-N) and exhibit only low levels of ecto-ATPase activity, whereas LCL-cells usually express both enzymes to varying degrees. There is a certain correlation (r = 0.75) between 5'-N and ecto-ATPase. When cAMP formation in response to agonists of the A2-type (stimulating) adenosine receptor is measured in the same cell lines there is no correlation with the expression of ecto-nucleotidases. Within pairs of BL and LCL cell lines derived from the same donor, an inverse relationship between ecto-nucleotidases and the response to the adenosine receptor agonist N-ethyl-carboxamido-adenosine (NECA) is observed. BL cells show a good response to NECA, whereas this is low or absent in LCL cells. Treatment of cells which exhibit both 5'-N and the adenosine receptor with specific polyclonal or monoclonal antibodies against the enzyme does not impair the function of the receptor. Antisera against peptides of the membrane antigen BNLF I-MA, coded by the EBV-genome, do not co-precipitate 5'-N out of detergent extracts of LCL-cells. In both cases 5'-N cannot be closely associated with other membrane components. The differences between BL and LCL cells in ectonucleotidases and the adenosine receptor appear to be fairly stable phenotypical markers, independent of other parameters and suitable for use in distinguishing these cells in all populations.

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Properties and Expression of an ATP-Degrading Ectoenzyme Cascade on Human Lymphoid Cells

Cited by 8 publications

References 17 publications

Ectonucleotidase Activities Associated with Cholinergic Synaptosomes Isolated from Torpedo Electric Organ

Ectonucleotidase Activities Associated with Cholinergic Synaptosomes Isolated from Torpedo Electric Organ

Production of Adenosine from Extracellular ATP at the Striatal Cholinergic Synapse

Qualitative and quantitative differences between Burkitt lymphoma and lymphoblastoid cell lines in the expression of membrane ecto‐nucleotidases and in the response to agonists of the A₂‐type adenosine receptor

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Properties and Expression of an ATP-Degrading Ectoenzyme Cascade on Human Lymphoid Cells

Cited by 8 publications

References 17 publications

Ectonucleotidase Activities Associated with Cholinergic Synaptosomes Isolated from Torpedo Electric Organ

Ectonucleotidase Activities Associated with Cholinergic Synaptosomes Isolated from Torpedo Electric Organ

Production of Adenosine from Extracellular ATP at the Striatal Cholinergic Synapse

Qualitative and quantitative differences between Burkitt lymphoma and lymphoblastoid cell lines in the expression of membrane ecto‐nucleotidases and in the response to agonists of the A2‐type adenosine receptor

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Qualitative and quantitative differences between Burkitt lymphoma and lymphoblastoid cell lines in the expression of membrane ecto‐nucleotidases and in the response to agonists of the A₂‐type adenosine receptor