Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027819 (neuroblastoma)
 27,800 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Incubation of the neuroblastoma x glioma hybrid cell line NG108-15 in tissue culture with dibutyryl cyclic AMP (1 mM) for up to 8 days produced a morphological differentiation of the cells, during which they extended neurite-like processes. Pertussis-toxin-catalysed ADP-ribosylation indicated that amounts of guanine-nucleotide-binding proteins (G-proteins), which are substrates for this toxin, were approximately doubled in membranes from the 'differentiated' cells in comparison with the control cells. Immunoblotting of membranes derived from either untreated or dibutyryl cyclic AMP-treated cells with anti-peptide antisera specific for the alpha subunits of the pertussis-toxin-sensitive G-proteins Gi and Go demonstrated that amounts of these G-proteins were reciprocally modulated during the differentiation process. In comparison with the untreated cells, the amount of Gi in the 'differentiated' cells was decreased, whereas the amount of Go was substantially increased. Stimulation of high-affinity GTPase activity in response to opioid peptides, which in this cell line interact with an opioid receptor of the delta subclass, was much decreased, and inhibition of adenylate cyclase activity was almost entirely attenuated in the 'differentiated'-cell membranes in comparison with membranes of untreated cells. Opioid receptor number was also decreased in membranes of the dibutyryl cyclic AMP-treated cells in comparison with the control cells. These data demonstrate that relatively small changes in the observed pattern of pertussis-toxin-catalysed ADP-ribosylation of membranes can mask more dramatic alterations in amounts of the individual pertussis-toxin-sensitive G-proteins, and further demonstrate the importance of methodologies able to discriminate between the different gene products.
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PMID:Differential regulation of amounts of the guanine-nucleotide-binding proteins Gi and Go in neuroblastoma x glioma hybrid cells in response to dibutyryl cyclic AMP. 285 96

Bordetella pertussis, the pathogen responsible for whooping cough, releases a soluble calmodulin-sensitive adenylate cyclase into its culture medium. Recently, Confer and Eaton [Confer, D., & Eaton, J. (1982) Science (Washington, D.C.) 217, 948-950], as well as Hanski and Farfel [Hanski, E., & Farfel, Z. (1985) J. Biol. Chem. 290, 5526-5536], have shown that crude extracts from B. pertussis containing adenylate cyclase activity cause elevations in intracellular cAMP when incubated with human neutrophils or lymphocytes. These investigators proposed that the bacterial enzyme enters animal cells and catalyzes the formation of cAMP from intracellular ATP. In this study, B. pertussis adenylate cyclase was purified to remove contaminating islet activating protein and examined for its effects on intracellular cAMP levels of human erythrocytes and N1E-115 mouse neuroblastoma cells. In both cases, the enzyme catalyzed the formation of intracellular cAMP. Addition of calmodulin to the adenylate cyclase preparations completely inhibited formation of intracellular cAMP catalyzed by the bacterial enzyme, indicating that cAMP was not synthesized extracellularly and then taken up by the cells. These experiments illustrate that the bacterial enzyme does enter animal cells and that the enzyme-calmodulin complex does not.
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PMID:Calmodulin inhibits entry of Bordetella pertussis adenylate cyclase into animal cells. 286 77

The cellular mechanism of action of the cannabimimetic drugs is examined using cultured cells. In membranes from N18TG2 neuroblastoma cells and the neuroblastoma X glioma hybrid cells, NG108-15, the psychoactive cannabinoid drugs and their nantradol analogs could inhibit adenylate cyclase activity. This response was not observed in either the soluble adenylate cyclase from rat sperm or membrane-bound adenylate cyclases from C6 glioma or S49 lymphoma cells. This cellular selectivity provides further evidence for the existence of specific receptors for the cannabimimetic compounds. Receptor-mediated inhibition of adenylate cyclase requires the presence of a guanine nucleotide-binding protein complex, Gi. Gi can be functionally inactivated as a result of an ADP-ribosylation modification catalyzed by pertussis toxin. The present study demonstrates that pertussis toxin treatment of cells abolished the cannabimimetic response in intact cells and in membranes derived therefrom. The action of pertussis toxin required NAD+ as substrate for in vitro modification of neuroblastoma membranes. Furthermore, pertussis toxin was able to catalyze the labeling of a neuroblastoma membrane protein in vitro using [32P] NAD+ under conditions similar to those by which attenuation of the cannabimimetic inhibition of adenylate cyclase could be demonstrated. This evidence demonstrates the requirement for a functional Gi in the action of cannabimimetic drugs.
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PMID:Involvement of Gi in the inhibition of adenylate cyclase by cannabimimetic drugs. 286 5

Bordetella pertussis, the etiologic agent of whooping cough, produces a calmodulin-sensitive adenylate cyclase which elevates intracellular cAMP in a variety of eucaryotic cells. Exogenous calmodulin added to the partially purified adenylate cyclase has been shown to inhibit invasion of animal cells by this enzyme (Shattuck, R. L., and Storm, D. R. (1985) Biochemistry 24, 6323-6328). In this study, several properties of the calmodulin-sensitive adenylate cyclase are shown to be influenced by Ca2+ in the absence of calmodulin. The presence or absence of Ca2+ during QAE-Sephadex ion exchange chromatography produced two distinct chromatographic patterns of adenylate cyclase activity. Two different forms of the enzyme (Pk1 and Pk2EGTA) were isolated by this procedure. Pk1 adenylate cyclase readily elevated intracellular cAMP levels in mouse neuroblastoma cells (N1E-115) while Pk2EGTA adenylate cyclase had no effect on cAMP levels in these cells. Gel exclusion chromatography of Pk1 adenylate cyclase gave apparent Stokes radii (RS) of 43.5 A (+/- 1.3) in the presence of 2 mM CaCl2 and 33.8 A (+/- 0.94) in the presence of 2 mM EGTA [( ethylenebis (oxyethylenenitrilo)]tetraacetic acid). These Stokes radii are consistent with molecular weights of 104,000 (+/- 6,400) and 61,000 (+/- 3,600), respectively. Pk2EGTA adenylate cyclase had an apparent RS of 33.0 (+/- 1.2) (Mr = 60,600 (+/- 2,800] in the presence of Ca2+ or excess EGTA. At 60 degrees C, Pk1 adenylate cyclase exhibited a Ca2+-dependent heat stability with a half-life for loss of enzyme activity of 10.3 min in 5 mM CaCl2 and a half-life of 2.8 min in the presence of 0.1 microM CaCl2. The stability of Pk2EGTA adenylate cyclase was not affected by changes in free Ca2+. The adenylate cyclase preparations described above were submitted to sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis, and enzyme activity was recovered from gel slices by extraction with detergent containing buffers. The catalytic subunit isolated from SDS-polyacrylamide gels was activated 7-fold in the presence of Ca2+ with maximum activity observed at 1 microM free Ca2+. With both preparations, the apparent molecular weight of the catalytic subunit on SDS gels was 51,000 in the presence of 2 mM CaCl2 and 45,000 in the presence of 2 mM EGTA. The catalytic subunit of the enzyme was purified to apparent homogeneity by preparative SDS-polyacrylamide gel electrophoresis and resubmitted to SDS gel electrophoresis in the presence or absence of free Ca2+. The purified catalytic subunit also exhibited a Ca2+-dependent shift in its mobility on SDS gels.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:The interaction of Ca2+ with the calmodulin-sensitive adenylate cyclase from Bordetella pertussis. 289 1

Activation of muscarinic cholinergic receptors of 1321N1 human astrocytoma cells attenuates cyclic AMP accumulation. This effect results from an activation of phosphodiesterase with no direct inhibition of adenylate cyclase activity. In spite of this lack of coupling of muscarinic receptors to adenylate cyclase, guanine nucleotides reduce the apparent binding affinity of the agonist carbachol in a washed membrane preparation of 1321N1 cells. The order of potency for this effect is guanosine 5'-O-(3-thiotriphosphate) greater than 5'-guanylyl-imidodiphosphate = GTP = GDP; ATP has no effect. The occurrence of a Mr = 41,000 protein labeled in the presence of [32P]NAD and pertussis toxin as well as the occurrence of guanine nucleotide-mediated inhibition of forskolin-stimulated adenylate cyclase activity indicate that the functional inhibitory guanine nucleotide regulatory component of adenylate cyclase (Ni) is present in 1321N1 cells. Pertussis toxin pretreatment of NG108-15 neuroblastoma X glioma cells, which express muscarinic receptors that link through Ni to inhibit adenylate cyclase, blocked the GTP-sensitive, high affinity binding of carbachol. In contrast, pretreatment of 1321N1 cells with a concentration of pertussis toxin that blocked [32P]ADP ribosylation of the Mr = 41,000 substrate and GTP-mediated inhibition of forskolin-stimulated adenylate cyclase activity had no effect on GTP-sensitive high affinity binding of carbachol. These results suggest that muscarinic cholinergic receptors of 1321N1 cells couple to a guanine nucleotide regulatory protein that is distinct from Ni.
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PMID:Guanine nucleotide-sensitive, high affinity binding of carbachol to muscarinic cholinergic receptors of 1321N1 astrocytoma cells is insensitive to pertussis toxin. 298

The cellular cGMP content increased in response to a variety of receptor agonists, which activate [e.g., prostaglandin (PG) E1, E2, and F2 alpha] or inhibit (e.g., alpha-adrenergic, muscarinic, and opiate agonists) adenylate cyclase in neuroblastoma X glioma hybrid NG108-15 cells. The responses were additive when PGF2 alpha and enkephalin were mixed. The inhibitory guanine nucleotide regulatory protein (Ni) is involved in adenylate cyclase inhibition; this function of Ni is lost when it is ADP-ribosylated by islet-activating protein (IAP), pertussis toxin [H. Kurose, T. Katada, T. Amano, and M. Ui (1983) J. Biol. Chem. 258, 4870-4875]. The cGMP rise induced by stimulation of the receptors linked to adenylate cyclase inhibition was also diminished by IAP; the time course and dose response for the IAP-induced diminution were the same between adenylate cyclase inhibition and cGMP generation. Ni thus appears to mediate guanylate cyclase activation as well as adenylate cyclase inhibition initiated via the same receptors. Melittin also increased cGMP. No additivity was shown when enkephalin and melittin were combined, suggesting that phospholipase A2 might play a role in Ni-mediated guanylate cyclase activation. On the other hand, the PGF2 alpha-induced cGMP rise was associated with increased incorporation of 32Pi into phosphatidylinositol; was not affected by cholera toxin, IAP or forskolin; and showed no additivity when combined with A23187, which increased cGMP by itself. PGs would occupy receptors linked to phosphatidylinositol breakdown, thereby increasing the availability of intracellular Ca2+, which is responsible for guanylate cyclase activation. Thus, dual pathways are proposed for a receptor-mediated cGMP rise in NG108-15 cells.
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PMID:Dual pathways of receptor-mediated cyclic GMP generation in NG108-15 cells as differentiated by susceptibility to islet-activating protein, pertussis toxin. 298 51

As noted previously, in N1E-115 neuroblastoma cells, carbamylcholine, a muscarinic cholinergic agonist, increased cGMP over 15-fold and decreased basal and prostaglandin E1 (PGE1)-stimulated cAMP content. In contrast to the stimulatory effects of PGE1 on cAMP, which were immediate, the carbamylcholine-induced decrease in basal and PGE1-stimulated cAMP exhibited a delay. The delay in carbamylcholine inhibition was independent of the extent of adenylate cyclase activation. Although basal cAMP content was suppressed within 30 sec after addition of carbamylcholine, inhibition was not maximal for at least 2 min following agonist addition; the delay was similar in cells exposed to PGE1 for 10 min prior to carbamylcholine but could be eliminated by incubation of the cells with muscarinic cholinergic agonist for 5 min prior to addition of prostaglandin. N1E-115 neuroblastoma cells possess a 41,000-Da membrane protein believed to be a component of the inhibitory GTP-binding protein of adenylate cyclase that is ADP ribosylated by pertussis toxin. Incubation of the cells with pertussis toxin prior to the addition of carbamylcholine reduced the maximal extent of inhibition of cAMP content and prevented the [32P]ADP-ribosylation of a 41,000-Da protein by toxin and [32P]NAD in membrane preparations from these cells. Incubation of cells with pertussis toxin, however, did not significantly alter the dose-response curve for carbamylcholine effects on cGMP. Even high concentrations of carbamylcholine, effective in stimulating cGMP, had minimal effects on cAMP content in toxin-treated cells; thus, ADP-ribosylation of Gi converts the adenylate cyclase but not the guanylate cyclase system to an agonist-insensitive state.
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PMID:Effects of pertussis toxin on cAMP and cGMP responses to carbamylcholine in N1E-115 neuroblastoma cells. 299 40

Chronic treatment of neuroblastoma X glioma NG108-15 hybrid cells with 10 nM [D-Ala2,D-Leu5] enkephalin (DADLE) results in a reduction of cell-surface opiate delta receptors. Whether opiate receptor internalization requires the activation of the guanine nucleotide-binding protein (Ni) is unclear. Hence, activation of Ni was attenuated by treating hybrid cells with 100 ng/ml pertussis toxin (PT) for 3 h, which resulted in a decrease in DADLE's ability to inhibit adenylate cyclase activity. Despite this prior treatment with PT, chronic exposure of these cells to 10 nM DADLE resulted in a time-dependent decrease in both [3H]diprenorphine and [3H]DADLE binding. This reduction in 3H-ligand binding in cells previously treated with PT represented internalization of the receptors because translocation was observed of bound [3H]DADLE from plasma membrane fractions to the lysosomal fractions in the Percoll gradients. Thus, opiate receptors internalize without activation of Ni. The internalization of opiate receptors was not accompanied by Ni. By measuring the amount of the 41-kDa alpha subunit being labeled by PT with [32P]NAD+, it was determined that plasma membrane preparations, of both the control cells and cells treated with 10 nM of DADLE for 4 h, contained equal concentrations of Ni, 2 pmol of Ni/mg of protein. Additionally, there was no measurable alteration in the amount of PT substrate in the lysosomal fractions of the DADLE-treated cells as compared to that of control cells. Chronic DADLE treatment resulted in a decrease in Km value of NAD+ in the ADP-ribosylation of 41-kDa subunit of Ni. In summary, opiate receptors internalize as agonist-receptor complexes without the guanine nucleotide-binding component.
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PMID:Effect of pertussis toxin treatment on the down-regulation of opiate receptors in neuroblastoma X glioma NG108-15 hybrid cells. 299 25

In membranes of neuroblastoma x glioma hybrid (NG108-15) cells, bradykinin (EC50 approximately equal to 5 nM) stimulates GTP hydrolysis by a high-affinity GTPase (Km approximately equal to 0.2 microM). The octapeptide, des-Arg9-bradykinin, was inactive. Stimulation of GTP hydrolysis by bradykinin and an opioid agonist was partially additive. Treatment of NG108-15 cells with pertussis toxin, which inactivates Ni, eliminated GTPase stimulation by the opioid agonist but not by bradykinin. The data suggest that bradykinin activates in NG108-15 membranes a guanine nucleotide-binding protein which is not sensitive to pertussis toxin and which may be involved in bradykinin-induced stimulation of phosphoinositide metabolism in these cells.
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PMID:Bradykinin stimulates GTP hydrolysis in NG108-15 membranes by a high-affinity, pertussis toxin-insensitive GTPase. 300 34

The tridecapeptide, neurotensin, inhibited prostaglandin E1-stimulated cyclic AMP production in intact plated neuroblastoma N1E115 cells. The peptide effect was concentration dependent (EC50 = 2 nM) and maximal inhibition reached 55% with 100 nM neurotensin. Acetyl neurotensin (8-13) was as active as neurotensin whereas neurotensins (1-8), (1-12), and (10-13) were barely active in inhibiting cyclic AMP production, thus showing the requirement of the carboxy terminal hexapeptide sequence of neurotensin for biological activity. The inhibitory effect of neurotensin on cyclic AMP production was largely prevented by pretreatment of N1E115 cells with islet-activating protein (pertussis toxin). In contrast, pertussis toxin did not inhibit neurotensin-stimulated cyclic GMP production in neuroblastoma cells. In cell membranes, the toxin promoted the selective ADP-ribosylation of a single protein having the same molecular weight (41,000) as the alpha-subunit of Ni, the inhibitory regulatory protein of adenylate cyclase. In membranes prepared from N1E115 cells, monoiodo[125I-Tyr3]neurotensin bound to a single population of receptors characterized, at 25 degrees and in the absence of monovalent cations and guanyl nucleotides, by a dissociation constant (Kd) of 56 pM and a maximal binding capacity (Bm) of 30 fmol/mg of protein. Na+ (10-100 mM) and GTP (0.1-100 microM) inhibited neurotensin binding in a concentration-dependent manner. At 100 mM Na+ and 100 microM GTP, receptor affinity was decreased by 5- and 2-fold, respectively. Li+ and K+ were less effective than Na+, and the effect of GTP was shared by GDP and guanyl-5'-yl-imidodiphosphate, but not by GMP, ATP, ADP, or adenyl-5'-yl-imidodiphosphate. It is concluded that in N1E115 cells, neurotensin attenuates cyclic AMP production by exerting an inhibitory effect on adenylate cyclase through an interaction of the peptide receptors with the regulatory GTP-binding protein Ni.
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PMID:Neurotensin-mediated inhibition of cyclic AMP formation in neuroblastoma N1E115 cells: involvement of the inhibitory GTP-binding component of adenylate cyclase. 301 77


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