2024
Identification of the potassium-binding site in serotonin transporter
Hellsberg E, Boytsov D, Chen Q, Niello M, Freissmuth M, Rudnick G, Zhang Y, Sandtner W, Forrest L. Identification of the potassium-binding site in serotonin transporter. Proceedings Of The National Academy Of Sciences Of The United States Of America 2024, 121: e2319384121. PMID: 38652746, PMCID: PMC11067047, DOI: 10.1073/pnas.2319384121.Peer-Reviewed Original ResearchConceptsSerotonin transporterSite-directed mutagenesis of residuesMutagenesis of residuesSite-directed mutagenesisHeterologous expression systemStudy of vesiclesNa2 siteClearance of serotoninPatch-clamp recordingsExpression systemBinding residuesSequential bindingMolecular dynamics simulationsBinding sitesPotassium binding siteSubstrate accumulationClamp recordingsVesiclesResiduesTurnover rateBindingStructural studiesChemical gradientsBinding configurationsSynaptic cleft
2018
Structural elements required for coupling ion and substrate transport in the neurotransmitter transporter homolog LeuT
Zhang YW, Tavoulari S, Sinning S, Aleksandrova AA, Forrest LR, Rudnick G. Structural elements required for coupling ion and substrate transport in the neurotransmitter transporter homolog LeuT. Proceedings Of The National Academy Of Sciences Of The United States Of America 2018, 115: e8854-e8862. PMID: 30181291, PMCID: PMC6156673, DOI: 10.1073/pnas.1716870115.Peer-Reviewed Original ResearchConceptsTransporter domainConformational changesOpen stateSodium symporter familyIon-substrate couplingTransmembrane ion gradientsSymporter familyNSS transportersSubstrate bindingLeuTIntracellular substratesCysteine accessibilitySubstrate transportAccessibility of substrateTyrosine residuesConformational responseNa2 siteUncoupled movementIon gradientsExtracellular pathwaysMechanistic componentsTransportersProteinTransport of ionsBinding
2015
Two Na+ Sites Control Conformational Change in a Neurotransmitter Transporter Homolog*
Tavoulari S, Margheritis E, Nagarajan A, DeWitt DC, Zhang YW, Rosado E, Ravera S, Rhoades E, Forrest LR, Rudnick G. Two Na+ Sites Control Conformational Change in a Neurotransmitter Transporter Homolog*. Journal Of Biological Chemistry 2015, 291: 1456-1471. PMID: 26582198, PMCID: PMC4714228, DOI: 10.1074/jbc.m115.692012.Peer-Reviewed Original ResearchMeSH KeywordsAmino Acid SubstitutionAmino Acid Transport SystemsAquatic OrganismsBacterial ProteinsBinding SitesCysteineGram-Negative BacteriaLigandsLiposomesModels, MolecularMolecular Dynamics SimulationMutagenesis, Site-DirectedMutationPlasma Membrane Neurotransmitter Transport ProteinsProtein ConformationProtein FoldingProtein StabilityProteolipidsRecombinant ProteinsSodiumConceptsConformational changesTransmembrane helix 1Open conformational stateDependent conformational changesTransporter homologExtracellular gateProkaryotic homologCytoplasmic pathwayHelix 1Interaction networksIntermediary interactionsBiophysical assaysNeurotransmitter transportersSubstrate pathwayNa2 siteConformational statesHelix motionsLeuTDirect interactionDependent closureHomologMutantsDistinct stepsResiduesComputational analysis
2013
How do transporters couple solute movements?
Rudnick G. How do transporters couple solute movements? Molecular Membrane Biology 2013, 30: 355-359. PMID: 24147977, PMCID: PMC4077868, DOI: 10.3109/09687688.2013.842658.Peer-Reviewed Reviews, Practice Guidelines, Standards, and Consensus Statements
2012
The Mechanistic Basis for Noncompetitive Ibogaine Inhibition of Serotonin and Dopamine Transporters*
Bulling S, Schicker K, Zhang YW, Steinkellner T, Stockner T, Gruber CW, Boehm S, Freissmuth M, Rudnick G, Sitte HH, Sandtner W. The Mechanistic Basis for Noncompetitive Ibogaine Inhibition of Serotonin and Dopamine Transporters*. Journal Of Biological Chemistry 2012, 287: 18524-18534. PMID: 22451652, PMCID: PMC3365767, DOI: 10.1074/jbc.m112.343681.Peer-Reviewed Original Research
2010
Reconstructing a Chloride-binding Site in a Bacterial Neurotransmitter Transporter Homologue*
Tavoulari S, Rizwan AN, Forrest LR, Rudnick G. Reconstructing a Chloride-binding Site in a Bacterial Neurotransmitter Transporter Homologue*. Journal Of Biological Chemistry 2010, 286: 2834-2842. PMID: 21115480, PMCID: PMC3024779, DOI: 10.1074/jbc.m110.186064.Peer-Reviewed Original ResearchConceptsChloride-binding siteConformational changesAdjacent binding sitesSingle point mutationProkaryotic homologuesSubstrate translocationIon-binding sitesTransporter homologueTransport proteinsNeurotransmitter transportersNeurotransmitter transportPoint mutationsBinding sitesHomologuesProteinMutationsCl(-) bindsDirect evidenceTherapeutic drugsSitesDependent formTranslocationTransportersBindsResidues
2008
Mechanism for alternating access in neurotransmitter transporters
Forrest LR, Zhang YW, Jacobs MT, Gesmonde J, Xie L, Honig BH, Rudnick G. Mechanism for alternating access in neurotransmitter transporters. Proceedings Of The National Academy Of Sciences Of The United States Of America 2008, 105: 10338-10343. PMID: 18647834, PMCID: PMC2480614, DOI: 10.1073/pnas.0804659105.Peer-Reviewed Original ResearchConceptsNeurotransmitter transportersMammalian neurotransmitter transportersMammalian serotonin transporterTransmembrane helix 1Bacterial homologueIon-binding sitesTransporter familyExtensive mutagenesisHelix 1Similar repeatsLeuTConformational changesSerotonin transporterRepeatsAlternate conformationConformational differencesExtracellular pathwaysCytoplasmTransportersExtracellular spaceCysteine reagentCrystal structureConformationPathwayAccessibility measurements
2007
Interaction between lysine 102 and aspartate 338 in the insect amino acid cotransporter KAAT1
Castagna M, Soragna A, Mari S, Santacroce M, Betté S, Mandela P, Rudnick G, Peres A, Sacchi V. Interaction between lysine 102 and aspartate 338 in the insect amino acid cotransporter KAAT1. American Journal Of Physiology - Cell Physiology 2007, 293: c1286-c1295. PMID: 17626242, DOI: 10.1152/ajpcell.00190.2007.Peer-Reviewed Original ResearchMeSH KeywordsAmino Acid SequenceAmino Acid SubstitutionAmino Acid Transport Systems, NeutralAnimalsAspartic AcidBinding SitesBiological TransportCross-Linking ReagentsCysteineDithiothreitolFemaleInsect ProteinsKineticsLepidopteraLysineModels, MolecularMolecular Sequence DataOocytesPhenanthrolinesPotassiumProtein Structure, TertiarySequence Homology, Amino AcidSodiumTryptophanXenopus laevisConceptsSingle cysteine mutantsNeutral amino acid transporterSite-directed mutagenesisAmino acid transportersTransport-associated currentNSS transportersDouble mutantXenopus laevis oocytesCysteine mutantsWild typeDependent transportLysine 102MutantsSuper familyAcid transportersPermeation pathwayAmino acidsDisulfide bondsLaevis oocytesFunctional evidenceAsp338Leucine uptakeKAAT1Spatial organizationResidues
1997
The Third Transmembrane Domain of the Serotonin Transporter Contains Residues Associated with Substrate and Cocaine Binding*
Chen J, Sachpatzidis A, Rudnick G. The Third Transmembrane Domain of the Serotonin Transporter Contains Residues Associated with Substrate and Cocaine Binding*. Journal Of Biological Chemistry 1997, 272: 28321-28327. PMID: 9353288, DOI: 10.1074/jbc.272.45.28321.Peer-Reviewed Original ResearchAsparagineBinding SitesCarrier ProteinsCell LineCell MembraneCocaineCysteineEthyl MethanesulfonateHumansIndicators and ReagentsIsoleucineLigandsMembrane GlycoproteinsMembrane Transport ProteinsMesylatesMutagenesis, Site-DirectedNerve Tissue ProteinsProtein Structure, SecondarySerotoninSerotonin Plasma Membrane Transport ProteinsStructure-Activity RelationshipTyrosine
1996
Ion Coupling Stoichiometry for the Norepinephrine Transporter in Membrane Vesicles from Stably Transfected Cells (∗)
Gu H, Wall S, Rudnick G. Ion Coupling Stoichiometry for the Norepinephrine Transporter in Membrane Vesicles from Stably Transfected Cells (∗). Journal Of Biological Chemistry 1996, 271: 6911-6916. PMID: 8636118, DOI: 10.1074/jbc.271.12.6911.Peer-Reviewed Original ResearchConceptsMembrane vesiclesTransmembrane ion gradientsLLC-PK1 cellsMajor substrateTransport substratesTransfected CellsStably Transfected CellsIon gradientsCoupling stoichiometryNet positive chargeDA accumulationVesiclesSubstrate moleculesTransportersNorepinephrine transporterAccumulationCellsGamma-aminobutyric acidCotransportDAGradientStoichiometrySubstrateAbsenceTransport processes
1994
Stable expression of biogenic amine transporters reveals differences in inhibitor sensitivity, kinetics, and ion dependence.
Gu H, Wall S, Rudnick G. Stable expression of biogenic amine transporters reveals differences in inhibitor sensitivity, kinetics, and ion dependence. Journal Of Biological Chemistry 1994, 269: 7124-7130. PMID: 8125921, DOI: 10.1016/s0021-9258(17)37256-3.Peer-Reviewed Original ResearchAnimalsBinding SitesBiogenic AminesBiological TransportCarrier ProteinsCell LineDopamine Plasma Membrane Transport ProteinsHumansKineticsMembrane GlycoproteinsMembrane Transport ProteinsNerve Tissue ProteinsNorepinephrine Plasma Membrane Transport ProteinsRatsRecombinant ProteinsSerotonin Plasma Membrane Transport ProteinsSymportersTransfection
1990
Energetics of reserpine binding and occlusion by the chromaffin granule biogenic amine transporter.
Rudnick G, Steiner-Mordoch S, Fishkes H, Stern-Bach Y, Schuldiner S. Energetics of reserpine binding and occlusion by the chromaffin granule biogenic amine transporter. Biochemistry 1990, 29: 603-8. PMID: 2140052, DOI: 10.1021/bi00455a002.Peer-Reviewed Original ResearchMeSH KeywordsAdenosine TriphosphatasesAmmonium SulfateBinding SitesBiogenic AminesCarbonyl Cyanide m-Chlorophenyl HydrazoneCarrier ProteinsChloridesChromaffin GranulesChromaffin SystemDetergentsElectrochemistryHydrogen-Ion ConcentrationIonophoresKineticsLigandsMembrane PotentialsReserpineThermodynamicsThiocyanatesTime FactorsUreaConceptsBiogenic amine transportersReserpine bindingChromaffin granule membrane vesiclesAmine transportersAmine transportMembrane vesiclesDead-end complexIon translocationTransportersSubstrate moleculesBindingM ureaDelta pHTranslocationTriton XSodium dodecyl sulfateNeutral substrate moleculesTransmembraneHigh-affinity site
1988
Antidepressant binding to the porcine and human platelet serotonin transporters.
Humphreys C, Levin J, Rudnick G. Antidepressant binding to the porcine and human platelet serotonin transporters. Molecular Pharmacology 1988, 33: 657-63. PMID: 3380080.Peer-Reviewed Original Research
1981
Inhibition of platelet serotonin transport by propranolol.
Rudnick G, Bencuya R, Nelson P, Zito R. Inhibition of platelet serotonin transport by propranolol. Molecular Pharmacology 1981, 20: 118-23. PMID: 7290078.Peer-Reviewed Original Research
1976
Equilibrium between two forms of the lac carrier protein in energized and nonenergized membrane vesicles from Escherichia coli.
Rudnick G, Schuldiner S, Kaback H. Equilibrium between two forms of the lac carrier protein in energized and nonenergized membrane vesicles from Escherichia coli. Biochemistry 1976, 15: 5126-31. PMID: 791364, DOI: 10.1021/bi00668a028.Peer-Reviewed Original ResearchConceptsLac carrier proteinMembrane vesiclesCarrier proteinY gene productEscherichia coli ML 308P-nitrophenyl alphaD-lactateMembrane proteinsGene productsML 308Cryptic formVesicle membraneLactose transportElectrochemical gradientEscherichia coliEnergy couplingProteinVesiclesCarbonyl cyanideSimilar affinityCompetitive inhibitorHigh affinity formMembraneBindingFlow dialysis
1975
ACTIVE TRANSPORT IN ISOLATED BACTERIAL MEMBRANE VESICLES: BINDING OF β‐GALACTOSIDES TO THE LAC CARRIER PROTEIN
Kaback H, Rudnick G, Schuldiner S, Short S. ACTIVE TRANSPORT IN ISOLATED BACTERIAL MEMBRANE VESICLES: BINDING OF β‐GALACTOSIDES TO THE LAC CARRIER PROTEIN. Annals Of The New York Academy Of Sciences 1975, 264: 350-357. PMID: 769642, DOI: 10.1111/j.1749-6632.1975.tb31495.x.Peer-Reviewed Reviews, Practice Guidelines, Standards, and Consensus Statements