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Query: UMLS:C0043167 (
pertussis
)
19,595
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
In membranes of myeloid differentiated HL-60 cells, the chemotactic peptide N-formyl-methionyl-leucyl-phenylalanine stimulates phospholipase C via a
pertussis
toxin-sensitive G-protein but does not inhibit adenylyl cyclase. In these membranes, the chemotactic peptide markedly stimulates the cholera toxin-dependent [32P]ADP-ribosylation of two proteins with approximate molecular masses of 40 and 41 kDa, respectively. The radiolabeled proteins comigrate on sodium dodecyl
sulfate
-polyacrylamide gels with the two
pertussis
toxin substrates present in HL-60 membranes, alpha i2 and alpha i3. The effect of the chemotactic peptide is blocked by treatment of intact HL-60 cells with
pertussis
toxin. Peptide mapping studies using Staphylococcus aureus protease V8 reveal that the two radiolabeled proteins are structurally distinct. Thus, the agonist-activated formyl peptide receptor functionally interacts with two distinct
pertussis
toxin substrates, most likely with Gi2 and Gi3. As the third Gi protein, Gi1, appears to be absent from both HL-60 cells and from systems that clearly reveal hormonal inhibition of adenylyl cyclase, the results strongly suggest that primary structure alone does not suffice to determine which effector mechanism is regulated by a given Gi-protein.
...
PMID:Two distinct Gi-proteins mediate formyl peptide receptor signal transduction in human leukemia (HL-60) cells. 251 19
Vasopressin (V2) receptors were solubilized from porcine kidney membranes with the detergent egg lysolecithin. Binding of [3H]vasopressin to the solubilized fraction was rapid, specific, and saturable. The agonist dissociation constants observed in membranes and solubilized fractions were 1.7 +/- 0.3 and 2.3 +/- 0.2 nM, respectively. In competition binding experiments, the solubilized fraction exhibited the same pharmacological profile as the membranes. Chemical crosslinking of [125I]vasopressin to the solubilized fraction followed by sodium dodecyl
sulfate
-polyacrylamide gel electrophoresis analysis demonstrated a 62-kDa band which was specifically labeled with [125I]vasopressin. Vasopressin binding sites from the solubilized fractions were resolved by gel filtration and ultracentrifugation on a sucrose gradient. In addition, agonist high affinity binding to V2 receptors and its sensitivity to guanine nucleotides were preserved even after solubilization in the absence of prebound agonist prior to solubilization. Addition of guanine nucleotides such as GTP gamma S decreased the specific binding of [3H]arginine vasopressin to these solubilized fractions in a dose-dependent manner, suggesting the solubilization of a V2 receptor-G protein complex. [32P]ADP ribosylation of the solubilized fraction by cholera and
pertussis
toxins revealed specifically labeled proteins with molecular weights of 42,000-43,000 and 39,000-41,000, respectively, on sodium dodecyl
sulfate
polyacrylamide gels. Furthermore [35S]GTP gamma S binding to these solubilized fractions was enhanced by vasopressin, confirming that a significant proportion of the vasopressin receptors must be closely coupled to G proteins even when these receptors are solubilized in the absence of agonist. These results are in contrast with those reported for beta, alpha 2 adrenergic and D2 dopaminergic receptor systems, but in agreement with D1 dopaminergic and A1 adenosine receptors. The molecular mechanism responsible for this difference remains to be determined.
...
PMID:Solubilization of a guanine nucleotide-sensitive form of vasopressin V2 receptors from porcine kidney. 252 56
The structural organization of the low molecular mass form (43 kDa) of Bordetella
pertussis
adenylate cyclase was dissected taking advantage of the known sequence of the bacterial cya gene (Glaser, P., Ladant, D., Sezer, O., Pichot, F., Ullmann, A., and Danchin, A. (1988) Mol. Microbiol. 2, 19-30) and its low content of Trp and Met residues. Cleavage of the 43-kDa protein and of its complementary tryptic fragments (T25 and T18 peptides) with N-chlorosuccinimide and cyanogen bromide followed by sodium dodecyl
sulfate
-polyacrylamide gel analysis of digestion products allowed the following conclusions: (i) the catalytically active 43-kDa form of B.
pertussis
adenylate cyclase is within the first 400 residues of the protein encoded by the cya gene. T25 occupies the N-terminal domain of the protein (residues 1-235/237). Isolated T25 fragment exhibits a low but measurable enzymatic activity which indicates that it harbors the catalytic site; (ii) T18 which is the main calmodulin-binding domain, occupies the C-terminal segment of protein (residues 236/238-399) and is devoid of catalytic properties; (iii) the two complementary peptides T25 and T18 reassociated only in the presence of calmodulin, leading to significant recovery of the original activity. These results demonstrate that both fragments of the 43-kDa form of adenylate cyclase are essential for a high level of enzymatic activity.
...
PMID:Characterization of the calmodulin-binding and of the catalytic domains of Bordetella pertussis adenylate cyclase. 253 1
The muscarinic receptors in a B82 cell line which were transfected with the rat m1 muscarinic receptor gene (cTB10 cells) were studied by using radioligand binding assays. Their possible coupling to the hydrolysis of inositol lipids and cyclic AMP formation were also investigated. [(-)-[3H]Quinuclidinyl benzilate [(-)-[3H]QNB] binding to the intact cTB10 cells was saturable and displaceable by 1 microM atropine
sulfate
. The Kd and maximum binding values of (-)-[3H]QNB from saturation studies were 12 pM and 17 fmol/10(6) cells, respectively. Inhibition studies of (-)-[3H]QNB binding to intact cTB10 cells suggested that these muscarinic receptors are of the M1 type defined by their high affinity for pirenzepine and low affinity for AF-DX 116 [11-[2-diethylamino methyl-1-piperidinylacetyl]-5,11-dihydro-6H-pyrido(2,3-b) (1,4)benzodiazepine-6-one]. The muscarinic agonist carbachol stimulated [3H]inositol monophosphate accumulation in the cTB10 cells, which could be reversed by the muscarinic antagonists atropine, pirenzepine or AF-DX 116. The rank order of potency of the muscarinic antagonists in inhibiting carbachol-stimulated [3H]inositol monophosphate accumulation was atropine greater than pirenzepine greater than AF-DX 116, in agreement with that from ligand/(-)-[3H]QNB competition experiments.
Pertussis
toxin and 4 beta-phorbol, 12-beta-myristate, 13-alpha-acetate reduced carbachol-stimulated [3H]inositol monophosphate accumulation. Prostaglandin E1 stimulated cyclic AMP formation in the cTB10 cells. Carbachol at the concentration of 10 mM exhibited no stimulatory or inhibitor effect on the basal or prostaglandin E1-stimulated cyclic AMP formation. These results suggest that the muscarinic receptors encoded by the transfected m1 gene in the cTB10 cells are of the M1 type and are coupled to the hydrolysis of inositol lipids, possibly via a
pertussis
toxin sensitive G protein.
...
PMID:Pharmacological characterization of the M1 muscarinic receptors expressed in murine fibroblast B82 cells. 253 6
The gene encoding a catalytically active deletion peptide, the C180 peptide, of the S-1 subunit of
pertussis
toxin was engineered to facilitate mutagenesis at the Trp-26 (wild-type) coding sequence. A synthetic double-stranded oligonucleotide was inserted into the C180 gene such that all possible codons would be introduced into position 26. Seven individual mutants of the C180 peptide which possessed amino acid substitutions at residue 26 (collectively termed C180W26n peptides) were purified from periplasmic extracts of Escherichia coli. Each C180W26n peptide was present as a single major peptide that had an apparent molecular mass of between 20.9 and 24.5 kDa by sodium dodecyl
sulfate
-polyacrylamide gel electrophoresis, and each showed similar immunoreactivity relative to the C180 peptide. The C180W26n peptides demonstrated marked reduction of both ADP-ribosyltransferase and NAD glycohydrolase activities at 25 nM and 10 microM NAD, respectively. Kinetic analysis of the two most active mutants, C180W26F and C180W26Y, revealed that the major perturbation of NAD glycohydrolase activity was due to an increase (approximately 20-fold) in the Km for NAD between these mutants and the C180 peptide.
...
PMID:Role of tryptophan 26 in the NAD glycohydrolase reaction of the S-1 subunit of pertussis toxin. 255 99
Bordetella
pertussis
adenylate cyclase (AC) toxin is a calmodulin-activated adenylate cyclase enzyme which has the capacity to enter eukaryotic target cells and catalyze the conversion of endogenous ATP into cyclic AMP. In this work, the AC holotoxin molecule is identified and isolated. It is a single polypeptide of apparent 216 kDa as determined by sodium dodecyl
sulfate
-polyacrylamide gel electrophoresis. Monoclonal antibodies which immunoprecipitate AC activity from extracts of wild type B.
pertussis
(BP338) react with this 216-kDa band on Western blots, and it is absent from a transposon Tn5 mutant (BP348) specifically lacking AC toxin. Isolation of the 216-kDa protein to greater than 85% purity by hydrophobic chromatography, preparative sucrose gradient centrifugation, and affinity chromatography using either calmodulin-Sepharose or monoclonal antibody coupled to Sepharose 4B yields stepwise increases in AC toxin potency, to a maximum of 88.3 mumol of cAMP/mg of target cell protein/mg of toxin. Electroelution of the 216-kDa band following sodium dodecyl
sulfate
-polyacrylamide gel electrophoresis yields a preparation with both AC enzyme and toxin activities. These data indicate that this protein represents the AC holotoxin molecule.
...
PMID:Adenylate cyclase toxin from Bordetella pertussis. Identification and purification of the holotoxin molecule. 255 37
A procedure that is sufficiently simple and economical for use in clinical and public health laboratories for producing and purifying filamentous hemagglutinin (FHA) and determining antibodies to this major antigen of Bordetella
pertussis
in serum is described. High yields of FHA (40 to 80 mg/liter) were obtained in the supernatant by cultivating B.
pertussis
in modified CL medium. The FHA antigen was separated from
pertussis
toxin (PT) and other antigens by chromatography on hydroxylapatite. Removal of residual PT activity in the FHA fraction was effected by affinity absorption of PT with Fetuin immobilized to Sepharose 4B. The FHA was used as the antigen for determining titers of immunoglobulin G (IgG), IgA, and IgM to FHA in sera of patients with
pertussis
by an improved enzyme-linked immunosorbent assay. Development of the interfering background color commonly observed in conventional FHA enzyme-linked immunosorbent assay procedures was eliminated by washing the reaction wells with a buffer of high ionic strength before adding the peroxidase conjugates. In the absence of nonspecific background color, the reaction endpoints were easy to read. The FHA prepared by the procedure described was identical to a reference preparation of purified FHA in sodium dodecyl
sulfate
-polyacrylamide gel electrophoresis profiles and serological specificity assays. High yields of FHA were obtained from all four strains of B.
pertussis
tested in this study, indicating that the procedure for enhanced production of FHA may be generally applicable to other strains of B.
pertussis
. Results from tests of 50 serum specimens with clinical information on
pertussis
for FHA and PT antibodies by the assay procedures described exemplified the usefulness and caveats of serodiagnosis for
pertussis
.
...
PMID:Preparation of filamentous hemagglutinin from Bordetella pertussis and assay for serum antibodies to filamentous hemagglutinin and pertussis toxin for clinical and public health laboratories. 255 34
Insulin-like growth factors I and II (IGF-I and II) and insulin are chemotactic agents for the human melanoma cell line A2058. As shown in this report, the motility receptor mediating this response is the heterodimeric type I IGF receptor. These three factors are able to compete with 125I-labeled IGF-I for binding to the cell surface with IC50 values equal to approximately 2 (IGF-I), approximately 150 (IGF-II), and approximately 300 nM (insulin). Cross-linking of 125I-IGF-I to the cell surface with disuccinimidyl suberate followed by analysis with sodium dodecyl
sulfate
-polyacrylamide gel electrophoresis and autoradiography reveals a 130-kDa protein (reduced) consistent with the alpha component of a type I receptor and a 38-kDa protein which does not bind insulin, and thus could be another IGF-I cell surface binding protein. The anti-IGF-I receptor monoclonal antibody (alpha IR-3) also competes with labeled IGF-I in binding experiments. In contrast, a control monoclonal antibody, matched to alpha IR-3 with respect to IgG subclass, has no significant effect on IGF-I binding. While alpha IR-3 inhibits the motility induced by IGF-I, IGF-II, and insulin,
pertussis
toxin (0.01-1.0 micrograms/ml) has no significant effect on the motility induced by the insulin-like growth factors or insulin on this cell line. Therefore, the type I IGF receptor appears to mediate a highly potent
pertussis
toxin-insensitive motility response to IGF-I, IGF-II, and insulin. In contrast, motility induced by the autocrine motility factor, a cytokine produced by the A2058 cells, is not affected by alpha IR-3 but is extremely sensitive to
pertussis
toxin. When mixtures of autocrine motility factor and IGF-I are employed to induce chemotaxis, the resulting motility is greater than that induced by either agent alone. These data indicate that motility in this melanoma cell line can be initiated through multiple receptors that stimulate the cells by separate transduction pathways. This capability to respond to multiple stimuli could enhance the metastatic potential.
...
PMID:The type I insulin-like growth factor receptor is a motility receptor in human melanoma cells. 255 32
Somatostatin, morphine, and opioids inhibit transmitter release at intact neuromuscular junctions between ciliary ganglion neurons and the choroidal smooth muscle of the chick eye. Somatostatin and morphine, however, have no effect on release from terminals on the striated muscle target of the ciliary ganglion, the iris. In neuronal terminals of both the choroid and the iris, a high-affinity Na+-dependent choline uptake-mediated ACh synthesis is present at hatching. Both tissues exhibit a basal release of 3H-ACh which is potentiated severalfold during a 5 minute incubation in 55 mM K+ Tyrodes. Fifty percent of the basal release and 100% of the stimulated release are Ca2+ dependent and probably mediated through N-like voltage-dependent Ca2+ channels. Co-incubation of the choroid with 10 microM morphine
sulfate
blocks approximately 90% of the stimulated release. The same effect is seen with 100 nM somatostatin, 10 microM dynorphin, and 100 microM met-enkephalin arginine phenylalanine. Preincubation of the excised choroid with
pertussis
toxin (200 ng/ml) reverses the inhibitory effects of both morphine and somatostatin. In contrast, 3H-ACh release from terminals in the striated iris is not affected by either morphine or somatostatin at micromolar levels. These results suggest that both opiate and somatostatin receptors are present in the choroid target and that they may act through a final common pathway to modulate ACh release via G proteins. Second messengers such as cyclic AMP or diacylglycerol do not appear to mediate these effects; neither increasing cAMP levels in terminals nor activation of protein kinase C affects evoked release or its inhibition by morphine or other neuromodulators. It is unclear whether endogenous neuromodulation occurs in this system, although somatostatin-like immunoreactivity can be demonstrated in terminals of choroid neurons.
...
PMID:Opiate and peptide inhibition of transmitter release in parasympathetic nerve terminals. 256 61
The human gastric tumoral cell line HGT-1 was previously shown to contain a membrane somatostatin receptor negatively coupled to adenylate cyclase through a
pertussis
toxin-sensitive inhibitory GTP-binding regulatory protein (Gi) (Reyl-Desmars, F., Laboisse, C., and Lewin, M. J. M. (1986) Regul. Pept. 16, 207-215). In this study, we have solubilized this receptor in a free unoccupied form using Triton X-100 as detergent and [125I-Tyr11]somatostatin-14 to monitor specific binding. Furthermore, we have prepared a monoclonal antibody against a chromatographically enriched soluble receptor fraction and used this antibody (30F3) to immunopurify the receptor in conjunction with Sepharose-somatostatin-14 immunopurification and steric exclusion high pressure liquid chromatography (HPLC). The purified fraction showed 18,600-fold enrichment in terms of specific binding (i.e. from 0.6 +/- 0.05 to 11,300 +/- 830 pmol/mg of protein) and a single dissociation constant (kappa D) of 76 +/- 8 nM. On HPLC, it migrated as a single and symmetric 90-kDa peak. Moreover, after 125I-protein labeling, it gave a single 90-kDa band on sodium dodecyl
sulfate
-polyacrylamide gel electrophoresis autoradiography. On the other hand, the 30F3 monoclonal antibody immunoblotted with a single 90-kDa band contained in the HGT-1 cell membrane. We therefore suggest that this antibody is specific to the HGT-1 membrane somatostatin receptor, that this receptor has a molecular mass of 90 kDa, and that we have obtained a homogeneous preparation of nondenatured receptor suitable for further cloning studies.
...
PMID:Solubilization and immunopurification of a somatostatin receptor from the human gastric tumoral cell line HGT-1. 257 96
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