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)

Neurotransmitter receptor coupling to adenylate cyclase (AC) was studied in the cultured human neuroblastoma SK-N-MC cell line. Activation of beta-adrenoceptors with isoprenaline (ISO) or vasoactive intestinal polypeptide (VIP) receptors, increased AC activity in a dose-dependent manner. Preincubation with ISO and VIP induced a ligand specific, i.e. homologous type of desensitization of the respective receptor. Neuropeptide tyrosine (NPY) was able to inhibit ISO as well as VIP induced AC activity. The effect of NPY was totally abolished in cells pretreated with pertussis toxin to inactivate inhibitory G-proteins. Thus, SK-N-MC cells possess functionally coupled beta-adrenoceptors, VIP and NPY receptors, and may be used to study interactions between ligands and receptors which couple to the AC system.
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PMID:Beta-adrenoceptor, vasoactive intestinal polypeptide (VIP) and neuropeptide tyrosine (NPY) receptors functionally coupled to adenylate cyclase in the human neuroblastoma SK-N-MC cell line. 283 76

Detergent extraction of plasma membranes from differentiated HL60 cells, specifically labeled with the chemoattractant, formyl-Nle-Leu-Phe-Nle-[125I-Tyr] Lys, resulted in the solubilization of a receptor-radioligand complex. GTP-binding activity coeluted with the radioligand when the sodium cholate extract was purified by chromatography on wheat germ agglutinin-Sepharose 6MB. A molecular size of approximately 59 A was estimated for the lectin-Sepharose-purified receptor complex by gel filtration chromatography on Ultrogel AcA 34. The isolated complex eluted from the gel filtration column exhibited an enhanced rate of ligand dissociation in response to GTP gamma S. Approximately 0.65 mol of pertussis toxin substrate/mol of receptor was estimated following partial purification of the receptor-ligand complex by sequential chromatography on wheat germ agglutinin-Sepharose, DEAE-Fractogel, and Ultrogel AcA 34. The pertussis toxin substrate which copurified with the receptor was compared with two distinct G proteins, containing alpha-subunits of 40 and 41 kDa, previously purified from HL60 cell plasma membranes. Approximately 86% of the pertussis toxin substrate identified in the receptor preparation consisted of the 40-kDa polypeptide. Differences in the peptide maps indicate that the predominant G protein which coelutes with the receptor is distinct from the purified G protein with an alpha-subunit of 41 kDa but homologous to the purified G protein with an alpha-subunit of 40 kDa.
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PMID:The formylpeptide chemoattractant receptor copurifies with a GTP-binding protein containing a distinct 40-kDa pertussis toxin substrate. 283 15

We investigated the mechanisms of receptor-mediated stimulation of high-affinity GTPase activity in response to opioid peptides and to foetal-calf serum in membranes of the neuroblastoma X glioma hybrid cell line NG108-15. Increases in GTPase activity in response to both of these ligands was abolished by prior exposure of the cells to pertussis toxin. Pertussis toxin in the presence of [32P]NAD+ catalysed incorporation of radioactivity into a broad band of approx. 40 kDa in membranes prepared from untreated, but not from pertussis-toxin-pretreated, cells. Additivity studies indicated that the responses to opioid peptides and to foetal-calf serum were mediated by separate guanine-nucleotide-binding proteins (G-proteins). Whereas opioid peptides produced an inhibition of adenylate cyclase in membranes of untreated cells, foetal-calf serum did not. Affinity-purified antibodies which recognize the C-terminus of the inhibitory G-protein identified a 40 kDa polypeptide in membranes of NG108-15 cells. These antibodies attenuated opioid-stimulated high-affinity GTPase activity, but did not markedly affect the response to foetal-calf serum. We conclude that receptors for the opioid peptides function via the inhibitory G-protein (Gi), whereas foetal-calf serum activates a second pertussis-toxin-sensitive G-protein, which has a C-terminal sequence significantly different from that of Gi.
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PMID:Antibodies which recognize the C-terminus of the inhibitory guanine-nucleotide-binding protein (Gi) demonstrate that opioid peptides and foetal-calf serum stimulate the high-affinity GTPase activity of two separate pertussis-toxin substrates. 283 23

We have compared the effects of pretreatment of Swiss 3T3 cell with pertussis toxin on the stimulation of DNA synthesis and phosphoinositide hydrolysis in response to a wide variety of mitogens. The toxin substantially inhibited the stimulation of DNA synthesis in response to a phorbol ester or various peptide and polypeptide growth factors irrespective of their ability to activate phosphoinositidase C. Production of inositol phosphates in response to platelet-derived growth factor, fibroblast growth factor and prostaglandin F2 alpha were unaffected by the toxin while bombesin- and vasopressin-stimulated formation of inositol phosphates were inhibited by only 27 and 23% respectively. These results argue against a major role for a pertussis toxin-sensitive G protein in coupling any of these mitogen receptors to activation of a phosphoinositidase C. Furthermore, the results suggest that the widespread inhibitory effects of pertussis toxin on mitogen-stimulated DNA synthesis may be unrelated to the toxin's limited actions on phosphoinositide hydrolysis.
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PMID:Effects of pertussis toxin on growth factor-stimulated inositol phosphate formation and DNA synthesis in Swiss 3T3 cells. 283 33

Recently we demonstrated the presence in calf thymocytes of a GTP-binding protein (G-protein) composed of three polypeptides, 54, 41, and 27 kDa, which was physically and functionally associated with a soluble phosphoinositides-specific phospholipase C (PI-phospholipase C). The properties of this G protein were further investigated with the following results. 1) In addition to the ability to bind [35S]guanosine-5'-[gamma-thio]triphosphate (GTP gamma S), the G-protein exhibited GTPase activity, which was enhanced by Mg2+, phosphatidylethanolamine, phosphatidylserine, and phosphatidylinositol, but inhibited by sodium cholate, GTP gamma S and F-.2) The 54-kDa polypeptide was ADP-ribosylated by pertussis toxin and also by endogenous membrane-bound ADP-ribosyltransferase, but none of these three polypeptides was ADP-ribosylated by cholera toxin. 3) The G-protein did not cross-react with either anti-rat brain alpha 1 (alpha-subunit of inhibitory G-protein, G1), alpha 0 (alpha-subunit of other G1-like G-protein, G0) or beta gamma antibodies. 4) Incubation of this G Protein with GTP gamma S caused dissociation of the three polypeptides. 5) The 27 kDa polypeptide showed GTP-binding activity and enhanced the phosphatidylinositol 4,5-bisphosphate hydrolysis by purified PI-phospholipase C. These results suggest that the PI-phospholipase C-associated G-protein in calf thymocytes may be a novel one and that it is involved in the regulation of PI-phospholipase C activity.
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PMID:Properties of a novel GTP-binding protein which is associated with soluble phosphoinositides-specific phospholipase C. 283 52

The rat Sertoli cell in culture expresses A1 inhibitory adenosine receptors. In this study, we have used pertussis toxin as a tool to characterize the mechanism of action of adenosine on these cells. Cells were preincubated for 18-24 h with pertussis toxin, and the responses to FSH and to the adenosine analog phenylisopropyladenosine (PIA) were measured by assaying cAMP accumulation. The effect of toxin on adenosine receptors was also evaluated by measuring binding of the adenosine agonist cyclohexyladenosine (CHA). The total number of specific CHA-binding sites was reduced 60-70% in membranes prepared from cells cultured for 24 h in the presence of pertussis toxin; the binding sites remaining after treatment displayed no apparent change in affinity for [3H]CHA. The effect of guanine nucleotides on CHA binding was also reduced after toxin pretreatment, but not abolished. PIA inhibited FSH-stimulated cAMP accumulation by 70-80%. Maximal inhibition was observed at a concentration of 10 nM PIA, and the ED50 of the dose-response curve was 1 nM. Pretreatment of the Sertoli cell with pertussis toxin completely blocked the PIA inhibition. The pertussis toxin effect was time and dose dependent. Reversal of the inhibition was observed after 6 h of treatment with a maximal dose of toxin (100 ng/ml). The dose of toxin producing a half-maximal effect was 10-30 ng/ml. In addition to this blockade of purine nucleotide inhibitory effects, exposure of the Sertoli cell to pertussis toxin concentrations ranging from 1-400 ng/ml consistently led to a potentiation of the FSH response measured as cAMP accumulation. In cell-free preparations (crude particulate fraction of the Sertoli cells, or sucrose gradient-purified plasma membranes), pertussis toxin catalyzed the incorporation of [32P]ADP ribose into a polypeptide with a molecular mass of 40-41 K. This peptide had electrophoretic mobility similar to that of a partially purified guanine nucleotide-binding protein (Gi). These data indicate that adenosine A1 inhibitory receptors are coupled to an inhibitory component (Gi) of adenylate cyclase. In the Sertoli cell, inhibitory and stimulatory signals interact in a bimodal regulation of adenylate cyclase and intracellular cAMP.
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PMID:Adenosine inhibition of the hormonal response in the Sertoli cell is reversed by pertussis toxin. 283 71

Although dopamine inhibits PRL release from the normal anterior pituitary lactotroph, a conclusive demonstration of the mechanisms involved in this response has been impeded by the presence of other cell types in the anterior pituitary. To circumvent this problem, we have isolated a clonal cell line, designated MMQ, from the 7315a rat pituitary tumor. The MMQ cell is an exemplary model for our use because it only secretes PRL. Our studies show that dopamine inhibits secretagogue-induced PRL release from these cells. In addition, dopamine decreases the intracellular cAMP concentration in MMQ cells that have been exposed to forskolin, cholera toxin, or vasoactive intestinal polypeptide, each a stimulator of cAMP generation. This inhibition is, in turn, reversed by the dopamine antagonist haloperidol and by pertussis toxin, an inactivator of the GTP-binding coupling protein. Dopamine also decreases the uptake and fractional efflux of 45Ca2+ by MMQ cells that have been exposed to the calcium channel activator maitotoxin. It seems, therefore, that dopamine decreases PRL release from MMQ cells at least in part by decreasing intracellular cAMP levels and calcium uptake. In additional experiments, we have found that MMQ cells are responsive to somatostatin, estrogen, progesterone, and acetylcholine, but not to TRH, angiotensin II, neurotensin, or bombesin. Furthermore, these cells possess a functional protein kinase-C system, as evidenced by the increase in PRL release and decrease in stimulated intracellular cAMP levels that occur in response to treatment with phorbol diesters. We suggest that the MMQ cell line will prove a useful model system for study of the biochemical effects of dopamine and other factors that modify PRL release.
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PMID:Characterization of the MMQ cell, a prolactin-secreting clonal cell line that is responsive to dopamine. 284 8

The injection of killed whole-cell pertussis vaccine (PV), prepared from formulated Bordetella pertussis strains 5574 and 305, into mice was shown to produce a stimulating effect on hematopoiesis. This effect was manifested by an increase in the number of endogenic colonies developing in the spleen of mice on days 5 and 9 after their irradiation in a sublethal dose, by the sharp stimulation of the proliferative activity of splenic colony-forming units (CFUs) originating in the bone marrow and by the elevated CFUs level in the peripheral blood. The preliminary incubation of whole-cell PV with polymyxin B, cationic polypeptide selectively reacting with the lipid A moiety of lipopolysaccharide (LPS), led to a sharp decrease in the above-mentioned manifestations of hematopoietic effect of the vaccine, while incubation with cetavlon interacting with the polysaccharide moiety of LPS produced practically no effect on the capacity of the vaccine for stimulating hematopoiesis. The stimulating effect of whole-cell PV on hematopoiesis is supposedly due, to a great extent, to the lipid A moiety of LPS.
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PMID:[Polymyxin B suppresses the stimulating action of pertussis vaccine on hematopoiesis in mice]. 285 Dec 46

A gene library of Bordetella pertussis DNA was constructed in Escherichia coli using the broad-host-range cosmid vector pLAFR1. The average insert size was 24.9 kb. From 500 members of the gene library, clones were identified which complemented trpE, glnA and Thr- mutations in E. coli but none which complemented trpD, trpC, trpB, trpA, proA or Leu- mutations. Four clones were identified which complemented trpE in E. coli. Anthranilate synthase activity was detected in a trpE strain only when it harboured a plasmid from one of these clones; activity was repressed when tryptophan was included in the growth medium. Two clones were identified which complemented glnA of E. coli. A recombinant plasmid from one of these clones also restored some of the nitrogen acquisition functions of glnG and glnL in E. coli. Expression of several B. pertussis virulence-associated products (haemolysin, heat-labile toxin, adenylate cyclase, filamentous haemagglutinin, and the cell-envelope polypeptide of Mr 30,000) was not detected in 500 independent clones. However, by transferring the recombinant plasmids to a mutant of B. pertussis deficient in haemolysin and adenylate cyclase, a plasmid was identified which restored both these activities.
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PMID:Complementation of mutations in Escherichia coli and Bordetella pertussis by B. pertussis DNA cloned in a broad-host-range cosmid vector. 288 29

An oligonucleotide probe complementary to the beginning of the gene encoding the serotype 2(ST2) fimbrial subunit of Bordetella pertussis was synthesized and a cloned DNA fragment hybridizing with the probe identified and sequenced. Several lines of evidence indicate that an open reading frame with coding information for a polypeptide of 207 amino acids, including a 26-amino-acid signal sequence, is the ST2 gene. The protein deduced from the nucleotide sequence shows good agreement with the NH2-terminal amino acid sequence, amino acid composition and molecular weight of the purified fimbrial subunit. In addition, the proposed ST2 subunit is shown to have homology with other fimbrial subunits.
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PMID:Cloning and nucleotide sequence analysis of the serotype 2 fimbrial subunit gene of Bordetella pertussis. 289 65


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