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Query: UMLS:C0043167 (pertussis)
 19,595 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Evidence is shown that protein kinase C is the major kinase which can phosphorylate histone H-1 in a membrane fraction prepared from rabbit peritoneal neutrophils. Addition of phorbol-12-myristate-13-acetate (PMA) (0.1 microgram/ml) or guanosine-5'-(3-O-thio)triphosphate (GTP gamma S) (10 microM) to the membrane fraction results in an increase of the phosphorylation of histone H-1. To achieve this effect, calcium (20 microM) is required for GTP gamma S but not for PMA. The effect of GTP gamma S, but not PMA is inhibited in membranes obtained from cells pretreated with pertussis toxin. The kinase activity is also enhanced by treatment of the membrane with 10 microM of GppNHp or GTP but not with GDP, GMP, cGMP, ATP, ADP, AMP and cAMP. This is the first direct evidence that a GTP binding protein is involved in the activation of membrane associated protein kinase C.
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PMID:Regulation of membrane associated protein kinase C activity by guanine nucleotide in rabbit peritoneal neutrophils. 302 4

The interaction of nucleotides with pertussis toxin (PT), and their effects on the ability of the toxin to ADP-ribosylate pure Ni, were evaluated. [32P]ATP (10 nM) bound directly to dithiothreitol-activated PT. This binding was competitively inhibited by nucleotides and anions with the following IC50 concentrations in order of decreasing potency: ATP = ATP gamma S (adenosine-5'-O-(3-thiotriphosphate)) = 0.2-0.3 microM, GDP beta S (guanosine-5'-O-(2-thiodiphosphate)) = 2-3 microM, GTP gamma S (guanosine-5'-O-(3-thiotriphosphate)) = 10-15 microM, ADP = 20-25 microM, GTP = 30-40 microM, GMP-P(NH)P (guanyl-5'-yl imidodiphosphate) = 100-150 microM, GDP = 150-200 microM, Pi = SO4(2-) = 20 mM and Cl- = acetate = 30-35 mM. Treatment of PT with ATP, AMP-P(NH)P, GTP, GDP, or GDP beta S, resulted in a stimulated state of NAD+-Ni ADP-ribosyltransferase activity. Addition of ATP, AMP-P(NH)P (adenyl-5'-yl imidodiphosphate), GTP, GDP, and GDP beta S to the ADP-ribosylation reactions resulted in increased rates of ADP-ribosyl-Ni formation. It is concluded that these effects on the nucleotides are due to their action to stimulate the activity of PT. At concentrations of PT between 0.04 and 0.4 microgram/ml, the stimulation of ADP-ribosylation of Ni effected by nucleotides was hysteretic in nature, exhibiting an approximately 25-min long lag when GDP was used as the activating nucleotide. These lags decreased with increasing concentrations of PT, and were abolished by pretreatment of the toxin with GDP or ATP. Preliminary incubation of Ni with GDP had no effect on the lag in its ADP-ribosylation by non-nucleotide treated PT. Addition of divalent cations (Mg2+, Mn2+, and Ca2+) inhibited formation of ADP-ribosyl-Ni, possibly by causing aggregation and denaturation of Ni. This is the first demonstration that both adenine and guanine nucleotides interact directly with PT and act to stimulate its activity to ADP-ribosylate Ni, and that guanine nucleotides do so regardless of whether they are nucleoside di- or triphosphates.
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PMID:The interaction of nucleotides with pertussis toxin. Direct evidence for a nucleotide binding site on the toxin regulating the rate of ADP-ribosylation of Ni, the inhibitory regulatory component of adenylyl cyclase. 309 44

The role of Mg2+ in the GTP hydrolytic cycle was investigated by using purified subunits (G alpha and G beta, gamma) of the GTP-binding protein isolated from Bufo marinus rod outer segments (ROS). Mg2+ markedly stimulated the rate of GTP and guanosine-5'-O-(3-thiotriphosphate) (GTP gamma-s) binding to G alpha. This effect was especially striking in the presence of very small quantities of illuminated ROS disc membranes. GTP hydrolysis could occur in the absence of Mg2+, and Mg2+ increased the rate of GTP hydrolysis only about 50%. These data indicate that Mg2+ plays a fundamental role in amplification of the photon signal by markedly stimulating the rate of formation of GTP X G alpha complexes by very small amounts of illuminated rhodopsin while producing only a modest increase in the rate of GTP hydrolysis. Following hydrolysis of GTP, GDP X G alpha could reassociate with illuminated or unilluminated ROS disc membranes in the presence or absence of Mg2+. In the absence of guanine nucleotides, release of GDP from G alpha bound to illuminated disc membranes was detected in the presence or absence of Mg2+. Moreover, Mg2+ did not affect the rate of GDP release from membrane-bound G alpha. Illumination of B. marinus crude ROS disc membrane preparations markedly reduced pertussis toxin-mediated ADP-ribosylation of a 39,000 Mr (G alpha) protein in the presence but not in the absence, of Mg2+. Moreover, extensive dialysis of illuminated (but not unilluminated) crude ROS disc membranes against a Mg2+-containing buffer caused a marked reduction in the subsequent ADP-ribosylation of G alpha, even when Mg2+ was not present during the ADP-ribosylation step. This reduction was reversed by the addition of GDP or a GDP analogue (but not GMP or hydrolysis-resistant GTP analogues) during the ADP-ribosylation step. Dialysis of crude ROS disc membrane preparations (illuminated or unilluminated) against a Mg2+ -free buffer did not reduce the subsequent ADP-ribosylation of G alpha. These data indicate that Mg2+, in the presence of photolysed rhodopsin, can stimulate the release of GDP from crude preparations of ROS disc membranes. Four lines of evidence suggest that G alpha and G beta, gamma have Mg2+-binding site(s). When stored at 4 degrees C, in the absence of glycerol, G beta, gamma was more stable in the absence than in the presence of Mg2+.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:The GTP-binding protein of rod outer segments. II. An essential role for Mg2+ in signal amplification. 311 Jan 57

ADP ribosylation of membranes by pertussis toxin (PT) and cholera toxin (CT) was studied as a function of addition of ATP, various guanine nucleotides, Mg2+, and inorganic phosphate (Pi). ADP ribosylation of a 40 kilodalton (kDa) band by PT is markedly enhanced by ATP and GTP and is strongly inhibited by Pi or Mg2+. GTP analogs (GTP gamma S and GMP-adenyl-5'-yl imidodiphosphate) were less effective. In contrast, ADP ribosylation of two substrates for CT (of 42 and 50 kDa) is stimulated by Pi, Mg2+, and GTP or GTP analogs such as GTP gamma S, but is unaffected by ATP. These stimulatory conditions correlate well with GTP-mediated activation of stimulated nucleotide-binding regulatory component of adenyl cyclase. Optimal conditions for ADP ribosylation by PT do not correlate simply with conditions thought to lead to stabilization of an inactive form of inhibitory nucleotide-binding regulatory component of adenyl cyclase (Gi) or Gi-like protein; rather, the data suggest the involvement of both a stimulatory nucleotide site on PT (positively affected by either ATP or GTP) and a stabilizing site on the PT substrate (affected by GDP, GDP beta S, or GTP). Treatment of membranes with Lubrol PX increased ADP ribosylation by PT by as much as 25- to 30-fold, but inhibited the action of CT. Using defined conditions for ADP ribosylation by PT and CT, distinct labeling patterns were observed in thyroid, brain, corpus luteum, liver, heart, and erythrocytes membranes. All membranes were more intensely labeled by PT rather than CT.
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PMID:Adenosine diphosphate ribosylation of G proteins by pertussis and cholera toxin in isolated membranes. Different requirements for and effects of guanine nucleotides and Mg2+. 315 63

Human neutrophils can be permeabilized with the cholesterol complexing agent digitonin and then induced to secrete lysosomal constituents by increases in free Ca2+ alone. In order of increasing requirements for Ca2+, vitamin B-12 binding protein, lysozyme and beta-glucuronidase were released. A variety of guanine nucleotides were examined with respect to their abilities to modulate this response. GTP, along with its analogues 5'-guanylylimidodiphosphate (Gpp[NH]p) and guanosine-5'-O-[3-thio]-triphosphate (GTP[gamma S]) decreased the Ca2+ requirements for secretion of all three granule constituents by one third to one order of magnitude. This synergy was dependent upon the concentration of guanine nucleotides employed. The effects of Gpp[NH]p could be blocked with the inactive derivative GDP[beta-S]. The active guanine nucleotides, particularly GTP, served as stimuli in their own right. At high concentrations of Ca2+ and GTP, degranulation was strikingly inhibited; inhibition was also achieved with high concentrations of guanylyl[beta, gamma-methylene]diphosphate (Gpp[CH2]p). Both GDP and GMP were without any effect. When neutrophils were pretreated with pertussis toxin, granule discharge induced by fMet-Leu-Phe was almost completely blocked, as reported by others. If the neutrophils pretreated with pertussis toxin were then permeabilized with digitonin, the synergy between Ca2+ and the stimulatory guanine nucleotides was maintained. These data suggest the involvement of G-proteins in secretion induced by Ca2+; however, this response either uses a different G-protein or a different pool of G-proteins from those responses triggered by fMet-Leu-Phe.
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PMID:Guanine nucleotides reduce the free calcium requirement for secretion of granule constituents from permeabilized human neutrophils. 353 3

The efficacy of muscarinic-receptor agonists for stimulation of inositol phosphate formation and Ca2+ mobilization in intact 1321N1 human astrocytoma cells is correlated with their capacity for formation of a GTP-sensitive high-affinity binding complex in membranes from these cells [Evans, Hepler, Masters, Brown & Harden (1985) Biochem. J. 232, 751-757]. These observations prompted the proposal that a guanine nucleotide regulatory protein serves to couple muscarinic receptors to the phospholipase C involved in phosphoinositide hydrolysis in 1321N1 cells. Inositol phosphate (InsP) formation was measured in a cell-free preparation from 1321N1 cells to provide direct support for this idea. The formation of InsP3, InsP2 and InsP1 was increased in a concentration-dependent manner (K0.5 approximately 5 microM) by guanosine 5'-[gamma-thio]triphosphate (GTP[S]) in washed membranes prepared from myo-[3H]inositol-prelabelled 1321N1 cells. Both GTP[S] and guanosine 5'-[beta gamma-imido]triphosphate (p[NH]ppG) stimulated InsP formation by 2-3-fold over control; GTP, GDP and GMP were much less efficacious. Millimolar concentrations of NaF also stimulated the formation of inositol phosphates in membrane preparations from 1321N1 cells. In the presence of 10 microM-GTP[S], the muscarinic cholinergic-receptor agonist carbachol stimulated (K0.5 approximately 10 microM) the formation of InsP above that achieved with GTP[S] alone. The effect of carbachol was completely blocked by atropine. The order of potency of nucleotides for stimulation of InsP formation in the presence of 500 microM-carbachol was GTP[S] greater than p[NH]ppG greater than GTP = GDP. Pertussis toxin, at concentrations that fully ADP-ribosylate and functionally inactivate Gi (the inhibitory guanine nucleotide regulatory protein), had no effect on InsP formation in the presence of GTP[S] or GTP[S] plus carbachol. These data are consistent with the idea that a guanine nucleotide regulatory protein that is not Gi is involved in receptor-mediated stimulation of InsP formation in 1321N1 human astrocytoma cells.
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PMID:Guanine nucleotide-dependent pertussis-toxin-insensitive stimulation of inositol phosphate formation by carbachol in a membrane preparation from human astrocytoma cells. 380 Sep 73

When WBC264-9C cells are preincubated with pertussis toxin, chemotaxis is inhibited and ADP-ribosylation of a membrane protein with a subunit Mr 41,000 is observed. Both the inhibition of chemotaxis and the ADP-ribosylation by pertussis toxin display a similar time lag, temperature dependence, and pertussis toxin-concentration dependence. Although the inhibition of chemotaxis and the ADP-ribosylation of the membrane protein are qualitatively correlated, nearly complete inhibition of chemotaxis occurs when there is only partial ADP-ribosylation of the membrane protein. Pertussis toxin-catalyzed ADP-ribosylation of the Mr 41,000 protein in WBC264-9C membranes is stimulated by GDP, GTP, and to a lesser extent by GMP; the nonhydrolyzable GTP analog guanosine 5'-[beta, gamma-imido]triphosphate has no effect. WBC264-9C membranes have a high-affinity GTPase activity, which is partially inhibited in membranes from pertussis toxin-treated cells. Neither GTPase activity nor adenylate cyclase activity in membranes from WBC264-9C cells is affected by fMet-Leu-Phe, an attractant for these cells. Our results suggest that a guanine nucleotide binding protein may be involved in chemotaxis, but they do not indicate an involvement of adenylate cyclase.
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PMID:Pertussis toxin inhibition of chemotaxis and the ADP-ribosylation of a membrane protein in a human-mouse hybrid cell line. 385 5

Membrane-bound adenylyl cyclases from ram, dog, and human sperm are unresponsive to fluoride and guanylylimidodiphosphate [GMP-P(NH)P], two agents that stimulate the adenylyl cyclases of somatic cells by an action on the stimulatory guanine nucleotide-binding regulatory (Ns) component of adenylyl cyclase. We have investigated whether this is because the sperm cell catalytic unit is functionally uncoupled from Ns but, nevertheless, capable of interacting with it, or because the sperm cell adenylyl cyclase system is unique and regulated differently from that of somatic cells. Sperm cells were found to be deficient in Ns, as evidenced by the inability of detergent extracts from sperm cell membranes and fractions to reconstitute Ns-mediated regulation of the adenylyl cyclase of cyc- S49 cells. In addition, attempts to label Ns in sperm cell membranes by [32P]ADP ribosylation with cholera toxin revealed that, if present, Ns is less than 1% of that found in human erythrocyte membranes. This, however, was not the only reason for the unresponsiveness of sperm cell adenylyl cyclase, since fluoride stimulation of the sperm cell enzyme could not be induced by reconstituting it with Ns purified from human erythrocytes (hRBC). When intact hRBC membranes were added to sperm cell fractions in the presence of fluoride, the activities that resulted were greater than the sum of the individual activities. This apparent reconstitution of fluoride regulation of sperm cell adenylyl cyclase could be blocked by lima bean trypsin inhibitor and appears to have resulted from proteolytic activation of the hRBC adenylyl cyclase by sperm proteases. Sperm cell membranes also appear to lack a functional inhibitory regulatory protein of the adenylyl cyclase system (Ni), since they did not contain an ADP-ribosylatable substrate for pertussis toxin action. These results suggest that the sperm cell adenylyl cyclase system is unique and different from that of somatic cells. Sperm cells appear to neither contain Ns or Ni nor possess the ability of their adenylyl cyclase system to interact with Ns from an exogenous source.
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PMID:The membrane-bound spermatozoal adenylyl cyclase system does not share coupling characteristics with somatic cell adenylyl cyclases. 391 51

Neuroblastoma X glioma hybrid cells NG108-15 were treated with a toxin derived from Bordetella pertussis. As compared to control cells grown in the absence of toxin, the inhibitory effects of opioid agonists upon cAMP formation were dose-dependently impaired by a non-competitive mechanism. Radioligand binding studies revealed that opioid agonist binding was dramatically reduced in toxin-treated membranes when tested in the presence of Na+/Mg++/GMP-PNP. Further, the potencies of guanine nucleotides to decrease opioid agonist binding were differentially modulated. These studies may facilitate our understanding of the mechanisms responsible for acute and chronic opiate effects.
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PMID:Pertussis toxin decreases opiate receptor binding and adenylate inhibition in a neuroblastoma x glioma hybrid cell line. 631 65

Attenuation of GTP-dependent inhibition of adenylate cyclase by islet-activating protein (pertussis toxin) is due to the ability of the toxin to catalyze the ADP-ribosylation of a 41,000/35,000-Da membrane-bound protein, which is thought to be the inhibitory guanine nucleotide-binding regulatory component of adenylate cyclase (Gi). We describe and document the purification of this protein from rabbit liver, and, in conjunction with evidence presented in the subsequent papers of the series, identify it as Gi. Purified Gi serves as an excellent substrate for islet-activating protein and can be ADP-ribosylated to the extent of 1 mol of ADP-ribose/mol of protein. The extent of ADP-ribosylation of Gi correlates with the amount of guanine nucleotide that can be bound to the protein. Studies of the nucleotide binding site on the 41,000-Da subunit of Gi reveal a high affinity site that is specific for guanine nucleotides. Rank order of affinities for various nucleotides is GTP gamma S greater than Gpp(NH)p = GTP = GDP greater than GMP much greater than App(NH)p, ATP. High affinity binding of guanine nucleotides is dependent on Mg2+ and is essentially irreversible in the presence of divalent cation. Bound nucleotide readily dissociates from its site on the 41,000-Da subunit of Gi in the absence of Mg2+. This reversal of binding is markedly enhanced by the presence of the 35,000-Da subunit of Gi. The physical characteristics of Gi are important determinants of its role as the inhibitory guanine nucleotide-binding regulatory component of adenylate cyclase.
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PMID:Purification and properties of the inhibitory guanine nucleotide-binding regulatory component of adenylate cyclase. 632 29


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