Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0043167 (pertussis)
 19,595 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Goldfish brain has a high density of [3H]kainate-binding sites, a subpopulation of which appears to be coupled to a pertussis toxin-sensitive G protein. We show here that a purified kainate receptor preparation reconstituted into phospholipid vesicles exhibits guanine nucleotide-sensitive high-affinity [3H]kainate binding. Pertussis toxin treatment abolishes the guanine nucleotide-sensitive portion of the [3H]kainate binding, and kainate promotes [3H]guanosine 5'-[beta,gamma-imido]triphosphate binding and [gamma-32P]GTP hydrolysis. Guanosine 5'-[gamma-thio]triphosphate (GTP[gamma S]) decreases the apparent Stokes radius of the soluble purified receptor preparation, consistent with dissociation of the kainate receptor-G protein complexes. The affinity-purified preparations contain proteins of 45, 41, and 35 kDa. The 45- and 41-kDa proteins crossreact with antibodies against the kainate receptor cloned from frog brain. The 35-kDa protein is recognized by an antiserum (SW) directed against the beta subunit of G proteins. When kainate receptors are purified in the presence of GTP[gamma S], the 35-kDa protein is no longer present. Also, [3H]kainate affinity is decreased and is no longer guanine nucleotide sensitive. Upon reconstitution with purified G proteins, high-affinity guanine nucleotide-sensitive binding and kainate-stimulated GTPase activity can be restored. These observations indicate that a kainate receptor from goldfish brain functionally interacts with a pertussis toxin-sensitive G protein.
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PMID:Coupling of a purified goldfish brain kainate receptor with a pertussis toxin-sensitive G protein. 131 52

Prostaglandin (PG) synthesis elicited by adrenergic transmitter in the vascular smooth muscle cells (VSMC) of rabbit aorta is primarily mediated through activation of alpha-2C and alpha-1A adrenergic receptors (ARs). We have now investigated and compared the signal transduction mechanisms involved in alpha-2C and alpha-1A AR-stimulated prostacyclin (PGI2) production, measured as 6-keto-PGF1 alpha, in vascular smooth muscle cells. Norepinephrine, methoxamine (an alpha-1 AR agonist) and UK-14304 (an alpha-2 AR agonist) enhanced 6-keto-PGF1 alpha production. UK-14304 and norepinephrine (in the presence of propranolol), but not methoxamine, reduced basal adenosine 2':3'-cyclic monophosphate (cyclic AMP) as well as forskolin- and isoproterenol-stimulated cyclic AMP accumulation. Forskolin and isoproterenol did not alter basal 6-keto-PGF1 alpha production and alpha AR agonist-induced 6-keto-PGF1 alpha production. Alpha-2C and alpha-1A AR-stimulated 6-keto-PGF1 alpha production was independent of cyclic AMP levels in vascular smooth muscle cells. Both alpha-2C and alpha-1A AR-stimulated 6-keto-PGF1 alpha production required extracellular Ca++. Pertussis toxin prevented inhibition of cyclic AMP accumulation and reduced 6-keto-PGF1 alpha production in response to AR agonists. Guanosine 5'-O-(3-thiotriphosphate) potentiated 6-keto-PGF1 alpha production induced by norepinephrine and UK-14304 but not by methoxamine, whereas at a higher Mg++ concentration (4 mM), guanosine 5'-O-(3-thiotriphosphate) potentiated 6-keto-PGF1 alpha production by all three agonists. In contrast, the effect of UK-14304 on cyclic AMP was prevented in the presence of 4 mM Mg++. These data suggest that the pertussis toxin-sensitive G protein(s) mediated the stimulation of PG synthesis by alpha-1A and alpha-2C AR activation and the decrease in cyclic AMP accumulation by alpha-2C AR activation.
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PMID:Comparison of signal transduction mechanisms of alpha-2C and alpha-1A adrenergic receptor-stimulated prostaglandin synthesis. 133 71

Guanine nucleotide-, neurotransmitter-, and fluoride-stimulated accumulation of [3H]inositol phosphates ([3H]InsPs) was measured in [3H]inositol-labeled synaptoneurosomes from cerebral cortex of immature (7-day-old) and adult rats, in order to clarify the role of GTP-binding proteins (G-proteins) in modulating phosphoinositide (PtdIns) metabolism during brain development. GTP(S) [Guanosine 5'-O-(3-thio)triphosphate] time- and concentration-dependently stimulated PtdIns hydrolysis. Its effect was potentiated by full (carbachol, metacholine) and partial (oxotremorine) cholinergic agonists through activation of muscarinic receptors. The presence of deoxycholate was required to demonstrate agonist potentiation of the guanine nucleotide effect. The response to GTP(S) was higher in adult than in immature rats, while the effect of cholinergic agonists was similar at the two ages examined. At both ages, histamine potentiated the effect of GTP(S), while norepinephrine was ineffective. At both ages, guanosine 5'-O-(2-thio)diphosphate [GDP(S)] and pertussis toxin significantly decreased GTP(S)-induced [3H]InsPs formation. The phorbol ester phorbol 12-myristate 13-acetate (PMA), on the other hand, did not inhibit the guanine nucleotide response in synaptoneurosomes from immature rats. NaF mimicked the action of GTP(S) in stimulating PtdIns hydrolysis. Its effect was not affected by carbachol and was highly synergistic with that of AlCl3, according to the concept that fluoroaluminate (AlF4-) is the active stimulatory species. No quantitative differences were found in the response to these salts between immature and adult animals. These results provide evidence that, in both the immature and adult rat brain, neuroreceptor activation is coupled to PtdIns hydrolysis through modulatory G-proteins.
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PMID:Guanine nucleotide- and muscarinic agonist-dependent phosphoinositide metabolism in synaptoneurosomes from cerebral cortex of immature rats. 136 Oct 27

Exposure to IFN-gamma increases the respiratory burst of polymorphonuclear leukocytes stimulated by the chemoattractant FMLP. However, the mechanism by which IFN-gamma alters the response to FMLP is unclear. We addressed the hypothesis that IFN-gamma enhances the response to FMLP by regulating the expression of elements of the formyl peptide receptor transmembrane-signaling pathway. HL-60 granulocytes were used as a model of FMLP transmembrane signaling. Formyl peptide receptor number and affinity were studied in isolated plasma membranes prepared from control HL-60 cells (CM) and cells exposed to IFN-gamma 100 U/ml for 24 h (IFN-M). Formyl peptide receptors were significantly increased on IFN-M compared with CM (1473 +/- 300 vs 3209 +/- 924). FMLP stimulates increased guanine nucleotide-binding protein (G protein) activation in IFN-M as evidenced by enhanced guanosine 5'-[gamma-thio]triphosphate binding and GTPase activity. Gi sub-unit content was increased in IFN-M as measured by pertussis toxin-catalyzed ADP-ribosylation and immunoblotting with antibodies against alpha i2 and alpha i3 G protein subunits. Guanosine 5'-[gamma-thio]triphosphate equilibrium binding demonstrated an increased number of G proteins coupled to formyl peptide receptors on IFN-M. We conclude that IFN-gamma increases expression of both formyl peptide receptors and G proteins coupled to these receptors, thereby enhancing FMLP-stimulated transmembrane signaling. Regulation of transmembrane signaling element expression may be a significant mechanism by which IFN-gamma regulates cellular functions.
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PMID:IFN-gamma enhances expression of formyl peptide receptors and guanine nucleotide-binding proteins by HL-60 granulocytes. 156 Feb 4

Zona pellucida (ZP)-induced acrosomal exocytosis in mammalian spermatozoa is thought to be mediated by signal transduction cascades similar to those found in hormonally responsive cells. In order to characterize this process further, we have examined the role of GTP-binding regulatory proteins (G proteins) in coupling sperm-ZP interaction to intracellular second messenger systems in mouse sperm. An in vitro signal transduction assay was developed to assess ZP-G protein dynamics in sperm membrane preparations. Guanosine 5'-3-O-(thio)triphosphate (GTP gamma S), a poorly hydrolyzable analogue of GTP, bound to these membranes in a specific and concentration-dependent fashion which reached saturation at 100 nM. Incubation of the membrane preparations with heat-solubilized ZP resulted in a significant increase in specific GTP gamma S binding in a concentration-dependent fashion with a half-maximal response at 1.25-2 ZP/microliters. Solubilized ZP also caused a significant increase in high affinity GTPase activity in the membranes over basal levels. Mastoparan increased specific GTP gamma S binding to the sperm membranes and stimulated high-affinity membrane GTPase activity to levels consistently greater than that seen with the solubilized ZP. Mastoparan, together with solubilized ZP, gave the same level of stimulation of GTP gamma S binding as mastoparan alone. Pertussis toxin completely inhibited the ZP-stimulated GTP gamma S binding, but only decreased mastoparan-stimulated GTP gamma S binding by 70-80%. Purified ZP3, the ZP component which possesses quantitatively all of the acrosomal exocytosis-inducing activity of the intact ZP, stimulated GTP gamma S binding to the same level as solubilized ZP; ZP1 and ZP2 did not stimulate GTP gamma S binding. ZP from fertilized eggs (ZPf), which does not possess acrosome reaction-inducing activity, also failed to stimulate GTP gamma S binding to sperm membranes. These data demonstrate the direct activation of a Gi protein in sperm membrane preparations in response to the ZP glycoprotein, ZP3, that induces the acrosome reaction. These data imply that Gi protein activation is an early event in the signal sequence leading to sperm acrosomal exocytosis.
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PMID:Activation of a Gi protein in mouse sperm membranes by solubilized proteins of the zona pellucida, the egg's extracellular matrix. 162 5

For the purpose to clarifying the biologically active substance of B. pertussis, we prepared the filamentous hemagglutinin (FHA) from culture supernatant of the strain Tohama phase I and purified it through chromatography columns of hydroxylapatite, fetuin-Sepharose 4B and Sepharose CL 6B. There are several bands appeared in the polyacrylamide gel after SDS-PAGE, especially between 98 kD and 210 kD. The amount of 210 kD component is not proportional to hemagglutination (HA) activity of FHA among five different lots. Irons et al. reported that FHA preparation degraded the 220 kD and 210 kD polypeptides during the storage would be reduced the specific HA activity. Our result pointed out that the HA activity of purified Foffdid not relate to 210 kD component only. For the quality control of FHA purity in the B. pertussis acellular vaccine, we suggest that it would be necessary to test both HA titer and SDS-PAGE results.
Zhonghua Min Guo Wei Sheng Wu Ji Mian Yi Xue Za Zhi 1991 Nov
PMID:[The property of filamentous hemagglutinin of Bordetella pertussis]. 184 42

The hydrolytic activity of microsomal phospholipase D from canine cerebral cortex was measured by a radiochemical assay using 1,2-dipalmitoyl-sn-glycerol-3-phosphoryl[3H]choline and 1-palmitoyl-2-[9,10(n)-3H]palmitoyl-sn-glycerol-3-phosphorylcholine as the exogenous substrates. Of several detergents tested, Triton X-100 was found to be the most effective in allowing expression of phospholipase D hydrolytic activity. The microsomal phospholipase D does not require any metal ion for its hydrolytic activity. Calcium and magnesium were slightly inhibitory between concentrations of 1 and 4 mM, but zinc was greatly inhibitory, causing a loss of greater than 90% activity at the 4 mM concentration. Non-hydrolyzable guanine nucleotide analogues such as guanosine 5'-(3-O-thio)triphosphate and guanyl-5'-yl-(beta, gamma-methylene)diphosphonate but not guanosine 5'-(2-thio)diphosphate were able persistently to stimulate phospholipase D hydrolytic activity at micromolar concentrations. Guanosine 5'-(2-thio)diphosphate was capable of partially blocking guanosine 5'-(3-O-thio)triphosphate stimulation of phospholipase D. Aluminum fluoride was able to cause a two- to threefold increase in hydrolytic activity of the phospholipase D. Cholera toxin had a stimulatory effect on the hydrolytic activity of phospholipase D, whereas islet-activating protein pertussis toxin had no effect. These results indicate that regulation of microsomal phosphatidylcholine phospholipase D activity by the guanine nucleotide-binding protein(s) in canine cerebral cortex may play an important role in signal transduction processes as well as in brain choline metabolism.
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PMID:Guanine nucleotide-binding protein regulation of microsomal phospholipase D activity of canine cerebral cortex. 210 44

Ligand binding properties of muscarinic receptors were examined in membranes and isolated cells prepared from bovine trachea. The binding of the muscarinic antagonist [3H]quinuclidinyl benzilate (QNB) to both membranes and isolated cells was saturable, reversible, and of high affinity [dissociation constant (KD) = 100-200 pM]. The binding constants of three selective antagonists, pirenzepine, AF-DX 116, and 4-DAMP, were examined, and the results indicate that the smooth muscle cells contain at least two receptor subtypes. The majority of receptors exhibit binding constants for these selective antagonists similar to those of the M2-subtype. AF-DX 116 binding curves indicated the presence of a small population of receptors with binding constants similar to those reported for the M3-subtype. These findings suggest that the smooth muscle cells may contain both M2- and M3-receptors and are in agreement with evidence of the presence of mRNAs coding for these two subtypes in tracheal extracts (A. Maeda, T. Kubo, M. Mishina, and S. Numa. FEBS Lett. 239: 339-342, 1988). [3H]QNB displacement curves of the muscarinic agonist oxotremorine were best described as a sum of binding to high- and low-affinity sites with KD values of 3.8 nM and 2.2 microM. Guanosine 5'-O-(3-thiotriphosphate) (GTP gamma S) shifted the high-affinity sites to low affinity, suggesting that the high-affinity sites may represent receptors coupled to G proteins. Pertussis toxin catalyzed the ADP ribosylation of a 40- to 41-kDa protein band present in the membranes but had no significant effect on high-affinity agonist binding, suggesting that most of the receptors are coupled to G proteins in a toxin-insensitive manner.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Ligand binding and G protein coupling of muscarinic receptors in airway smooth muscle. 211 Apr 18

The effect of the hydrolysis-resistant GTP analogs, guanosine 5'-O-(3-thiotriphosphate) (GTP gamma S) and guanylyl imidodiphosphate (GMPPNP), on norepinephrine (NE) secretion from digitonin-permeabilized rat pheochromocytoma cells, PC12, was examined. Although secretion in the presence of saturating Ca2+ (10 microM) was not affected by GTP gamma S or GMPPNP, secretion in the absence of Ca2+ was stimulated by these GTP analogs. Secretion induced by saturating concentrations of GTP gamma S or GMPPNP was approximately 80% of that induced by 10 microM Ca2+. Half-maximum stimulation was induced by 30 microM GTP gamma S or GMPPNP. Both Ca2(+)-stimulated and GTP gamma S-stimulated secretion were ATP dependent and inhibited by N-ethylmaleimide. The GTP gamma S-stimulated secretion of NE from permeabilized PC12 cells does not appear to result from either the release of Ca2+ or the activation of protein kinase C. Activation of protein kinase C by pretreatment of intact cells with 12-O-tetradecanoylphorbol 13-acetate caused a 50% increase in both Ca2(+)-stimulated and GTP gamma S-stimulated secretion. Cholera and pertussis toxins did not affect Ca2(+)-stimulated or GTP gamma S-stimulated NE secretion. Guanosine 5'-O-(2-thiodiphosphate) (GDP beta S) and GTP inhibited GTP gamma S-stimulated secretion but not Ca2(+)-stimulated secretion. The inability of GDP beta S to inhibit Ca2(+)-stimulated secretion indicates that the process affected by GTP gamma S is not an essential step in the Ca2(+)-stimulated pathway.
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PMID:Hydrolysis-resistant GTP analogs stimulate catecholamine release from digitonin-permeabilized PC12 cells. 211 52

To identify the involvement of dopamine receptors in the transmembrane signaling of the adenosine receptor-G protein-adenylate cyclase system in the CNS, we examined the effects of pertussis toxin (islet-activating protein, IAP) and apomorphine on A1 adenosine agonist (-)N6-R-[3H]phenylisopropyladenosine ([3H]PIA) and antagonist [3H]xanthine amine congener ([3H]XAC) binding activity and adenylate cyclase activity in cerebral cortex membranes of the rat brain. Specific binding to a single class of sites for [3H]XAC with a dissociation constant (KD) of 6.0 +/- 1.3 nM was observed. The number of maximal binding sites (Bmax) was 1.21 +/- 0.13 pmol/mg protein. Studies of the inhibition of [3H]XAC binding by PIA revealed the presence of two classes of PIA binding states, a high-affinity state (KD = 2.30 +/- 1.16 nM) and a low-affinity state (KD = 1.220 +/- 230 nM). Guanosine 5'-(3-O-thio)triphosphate or IAP treatment reduced the number of the high-affinity state binding sites without altering the KD for PIA. Apomorphine (100 microM) increased the KD value 10-fold and decreased Bmax by approximately 20% for [3H]PIA. The effect of apomorphine on the KD value increase was irreversible and due to a conversion from high-affinity to low-affinity states for PIA. The effect was dose dependent and was mediated via D2 dopamine receptors, since the D2 antagonist sulpiride blocked the phenomenon. The inhibitory effect of PIA on adenylate cyclase activity was abolished by apomorphine treatment. There was no effect of apomorphine on displacement of [3H]quinuclidinyl benzilate (muscarinic ligand) binding by carbachol. These data suggest that A1 adenosine receptor binding and function are selectively modified by D2 dopaminergic agents.
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PMID:Possible involvement of pertussis toxin-sensitive G proteins and D2 dopamine receptors in the A1 adenosine receptor-adenylate cyclase system in rat cerebral cortex. 214 96


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