Search results for "Rho protein"

showing 3 items of 3 documents

Rho protein inhibition blocks protein kinase C translocation and activation.

1998

Small GTP-binding proteins of the Ras and Rho family participate in various important signalling pathways. Large clostridial cytotoxins inactivate GTPases by UDP-glucosylation. Using Clostridium difficile toxin B-10463 (TcdB) for inactivation of Rho proteins (RhoA/Rac/Cdc42) and Clostridium sordellii lethal toxin-1522 (TcsL) for inactivation of Ras-proteins (Ras/Rac/Ral, Rap) the role of these GTPases in protein kinase C (PKC) stimulation was studied. Phorbol-myristate-acetate (PMA) induced a rapid PKC translocation to and activation in the particulate cell fraction as determined by PKC-activity measurements and Western blots for PKC alpha. These effects were blocked by TcdB inhibiting Rho …

LipopolysaccharidesRHOASwineBiophysicsClostridium difficile toxin ABronchiCell Cycle ProteinsGTPaseCDC42PKC alphaBiochemistryGTP-Binding ProteinsRHO protein GDP dissociation inhibitorAnimalsHumanscdc42 GTP-Binding ProteinMolecular BiologyProtein kinase CCells CulturedProtein Kinase CbiologyEpithelial CellsCell BiologyMolecular biologyCell biologyEnzyme ActivationCdc42 GTP-Binding Proteinbiology.proteinras ProteinsTetradecanoylphorbol AcetateEndothelium VascularrhoA GTP-Binding ProteinBiochemical and biophysical research communications
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Regulation of phospholipase D activity in synaptosomes permeabilized with Staphylococcus aureus alpha-toxin.

1998

In order to investigate the regulation of presynaptic phospholipase D (PLD) activity by calcium and G proteins, we established a permeabilization procedure for rat cortical synaptosomes using Staphylococcus aureus alpha-toxin (30-100 microg/ml). In permeabilized synaptosomes, PLD activity was significantly stimulated when the concentration of free calcium was increased from 0.1 microM to 1 microM. This activation was inhibited in the presence of KN-62 (1 microM), an inhibitor of calcium/calmodulin-dependent kinase II (CaMKII), but not by the protein kinase C inhibitor, Ro 31-8220 (1-10 microM). Synaptosomal PLD activity was also stimulated in the presence of 1 microM GTPgammaS. When Rho pro…

MaleStaphylococcus aureusCell Membrane PermeabilityG proteinBacterial ToxinsBiophysicschemistry.chemical_elementCalciumBiologyIn Vitro TechniquesBiochemistryClostridium difficile toxin Bchemistry.chemical_compoundHemolysin ProteinsStructural BiologyStaphylococcus aureus α-toxinCa2+/calmodulin-dependent protein kinaseSynaptosomeGeneticsPhospholipase DPhospholipase D activityAnimalsRats WistarMolecular BiologyProtein kinase CSynaptosomePhospholipase DRho proteinCalcium/calmodulin-dependent protein kinase IICell BiologyBrefeldin AMolecular biologyRatsEnzyme Activationenzymes and coenzymes (carbohydrates)BiochemistrychemistryGuanosine 5'-O-(3-Thiotriphosphate)lipids (amino acids peptides and proteins)CalciumSynaptosomesFEBS letters
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Role of glycine-82 as a pivot point during the transition from the inactive to the active form of the yeast Ras2 protein

1991

AbstractRas proteins bind either GDP or GTP with high affinity. However, only the GTP-bound form of the yeast Ras2 protein is able to stimulate adenylyl cyclase. To identify amino acid residues that play a role in the conversion from the GDP-bound to the GTP-bound state of Ras proteins, we have searched for single amino acid substitutions that selectively affected the binding of one of the two nucleotides. We have found that the replacement of glycine-82 of the Ras2 protein by serine resulted in an increased rate of dissociation of Gpp(NH)p, a nonhydrolysable analog of GTP, while the GDP dissociation rate was not significantly modified. Glycine-82 resides in a region that is highly conserve…

Saccharomyces cerevisiae ProteinsGTP'Guanosine diphosphateProtein ConformationRestriction MappingGlycineBiophysicsSaccharomyces cerevisiaeBiochemistryFungal ProteinsGTP-binding protein regulatorsProtein structureGTP-Binding ProteinsStructural BiologyEscherichia coliGeneticsRHO protein GDP dissociation inhibitorAmino Acid SequenceRas2Binding siteMolecular BiologyPeptide sequencechemistry.chemical_classificationGuanylyl ImidodiphosphateBinding SitesPoint mutationChemistryCell BiologyGuanosine triphosphateRecombinant ProteinsAmino acidModels StructuralBiochemistryMutagenesis Site-Directedras ProteinsS. cerevisaePlasmidsRasFEBS Letters
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