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
2003
Serotonin transporter missense mutation associated with a complex neuropsychiatric phenotype
Ozaki N, Goldman D, Kaye W, Plotnicov K, Greenberg B, Lappalainen J, Rudnick G, Murphy D. Serotonin transporter missense mutation associated with a complex neuropsychiatric phenotype. Molecular Psychiatry 2003, 8: 933-936. PMID: 14593431, DOI: 10.1038/sj.mp.4001365.Peer-Reviewed Original ResearchMeSH KeywordsAmino Acid SequenceAnorexia NervosaAsperger SyndromeAutistic DisorderCarrier ProteinsFemaleGenotypeHumansMaleMembrane GlycoproteinsMembrane Transport ProteinsMolecular Sequence DataMutation, MissenseNerve Tissue ProteinsObsessive-Compulsive DisorderPedigreePhenotypePhobic DisordersPolymorphism, Single-Stranded ConformationalProtein Structure, TertiarySerotonin Plasma Membrane Transport Proteins
2001
A Conformationally Sensitive Residue on the Cytoplasmic Surface of Serotonin Transporter*
Androutsellis-Theotokis A, Ghassemi F, Rudnick G. A Conformationally Sensitive Residue on the Cytoplasmic Surface of Serotonin Transporter*. Journal Of Biological Chemistry 2001, 276: 45933-45938. PMID: 11592963, DOI: 10.1074/jbc.m107462200.Peer-Reviewed Original ResearchA Lithium-induced Conformational Change in Serotonin Transporter Alters Cocaine Binding, Ion Conductance, and Reactivity of Cys-109*
Ni Y, Chen J, Androutsellis-Theotokis A, Huang C, Moczydlowski E, Rudnick G. A Lithium-induced Conformational Change in Serotonin Transporter Alters Cocaine Binding, Ion Conductance, and Reactivity of Cys-109*. Journal Of Biological Chemistry 2001, 276: 30942-30947. PMID: 11408487, DOI: 10.1074/jbc.m104653200.Peer-Reviewed Original Research
2000
Functional Role of Critical Stripe Residues in Transmembrane Span 7 of the Serotonin Transporter EFFECTS OF Na+, Li+, AND METHANETHIOSULFONATE REAGENTS*
Kamdar G, Penado K, Rudnick G, Stephan M. Functional Role of Critical Stripe Residues in Transmembrane Span 7 of the Serotonin Transporter EFFECTS OF Na+, Li+, AND METHANETHIOSULFONATE REAGENTS*. Journal Of Biological Chemistry 2000, 276: 4038-4045. PMID: 11058600, DOI: 10.1074/jbc.m008483200.Peer-Reviewed Original ResearchConceptsCys-109Methanethiosulfonate reagentsWater-filled poresNative cysteine residuesCysteine-containing mutantsExtracellular loop 1Close-contact regionThree-dimensional structureCysteine residuesTranslocation mechanismControl mutantsAlpha-helixMTSEA-biotinResidue positionsCysteine substitutionsLoop 1Conformational changesMTS reagentsFunctional roleMutantsIon bindingResiduesTransportersIon dependenceSerotonin transporterOligomerization of serotonin transporter and its functional consequences
Kilic F, Rudnick G. Oligomerization of serotonin transporter and its functional consequences. Proceedings Of The National Academy Of Sciences Of The United States Of America 2000, 97: 3106-3111. PMID: 10716733, PMCID: PMC16200, DOI: 10.1073/pnas.97.7.3106.Peer-Reviewed Original ResearchPermeation and gating residues in serotonin transporter
Chen J, Rudnick G. Permeation and gating residues in serotonin transporter. Proceedings Of The National Academy Of Sciences Of The United States Of America 2000, 97: 1044-1049. PMID: 10655481, PMCID: PMC15515, DOI: 10.1073/pnas.97.3.1044.Peer-Reviewed Original ResearchMeSH KeywordsAllosteric RegulationAmino Acid SubstitutionCarrier ProteinsChloridesCocaineHumansHydrogenIon Channel GatingIon TransportIsoleucineMembrane GlycoproteinsMembrane Transport ProteinsMesylatesMutagenesis, Site-DirectedNerve Tissue ProteinsNorepinephrine Plasma Membrane Transport ProteinsOxidation-ReductionPotassiumProtein BindingProtein ConformationProtein Structure, TertiaryRecombinant Fusion ProteinsReducing AgentsSerotoninSerotonin Plasma Membrane Transport ProteinsSodiumSulfhydryl CompoundsSymportersConceptsSubstrate permeation pathway
1999
The Role of External Loop Regions in Serotonin Transport LOOP SCANNING MUTAGENESIS OF THE SEROTONIN TRANSPORTER EXTERNAL DOMAIN*
Smicun Y, Campbell S, Chen M, Gu H, Rudnick G. The Role of External Loop Regions in Serotonin Transport LOOP SCANNING MUTAGENESIS OF THE SEROTONIN TRANSPORTER EXTERNAL DOMAIN*. Journal Of Biological Chemistry 1999, 274: 36058-36064. PMID: 10593887, DOI: 10.1074/jbc.274.51.36058.Peer-Reviewed Original ResearchConceptsChimeric transportersWild type SERTExternal loop 4High affinity cocaine analogSubsequent conformational changesExternal loop regionsTransmembrane segmentsInitial binding stepScanning mutagenesisWild typeExternal loopLigand bindingSerotonin transporterMutantsConformational changesLoop 4Loop regionConformational flexibilityTransportersCorresponding sequenceBinding stepExternal domainNorepinephrine transporterActivity 5NET substrateMolecular cloning, expression and characterization of a bovine serotonin transporter1The sequence reported in this paper has been deposited in the GenBank data base (accession number AF119122).1
Mortensen O, Kristensen A, Rudnick G, Wiborg O. Molecular cloning, expression and characterization of a bovine serotonin transporter1The sequence reported in this paper has been deposited in the GenBank data base (accession number AF119122).1. Brain Research 1999, 71: 120-126. PMID: 10407194, DOI: 10.1016/s0169-328x(99)00178-3.Peer-Reviewed Original ResearchMeSH KeywordsAmino Acid SequenceAnimalsCarrier ProteinsCattleCitalopramCloning, MolecularDesipramineFemaleFluoxetineHeLa CellsHumansImipramineKineticsMembrane GlycoproteinsMembrane Transport ProteinsMolecular Sequence DataNerve Tissue ProteinsN-Methyl-3,4-methylenedioxyamphetamineOrgan SpecificityParoxetinePhylogenyPregnancyRatsRecombinant ProteinsReverse Transcriptase Polymerase Chain ReactionSequence AlignmentSequence Homology, Amino AcidSerotoninSerotonin Plasma Membrane Transport ProteinsTransfectionConceptsSerotonin transporterHuman serotonin transporterExpression of SERTAdrenal glandBrain stemParathyroid glandsPharmacological profileBone marrowThyroid glandSmall intestinePharmacological targetsRT-PCR amplificationDecreased sensitivityExtracellular fluidGlandAmino acid differencesBiogenic aminesNeurotransmitter transportersDependent neurotransmitter transportersImportant antidepressantsAcid differencesDifferent tissuesAntidepressantsParoxetineDesipramine
1998
Critical Amino Acid Residues in Transmembrane Span 7 of the Serotonin Transporter Identified by Random Mutagenesis*
Penado K, Rudnick G, Stephan M. Critical Amino Acid Residues in Transmembrane Span 7 of the Serotonin Transporter Identified by Random Mutagenesis*. Journal Of Biological Chemistry 1998, 273: 28098-28106. PMID: 9774428, DOI: 10.1074/jbc.273.43.28098.Peer-Reviewed Original ResearchMeSH KeywordsAmino Acid SequenceAnimalsBiological TransportCarrier ProteinsMembrane GlycoproteinsMembrane Transport ProteinsModels, MolecularMolecular Sequence DataMutagenesisNerve Tissue ProteinsProtein ConformationRatsSerotoninSerotonin Plasma Membrane Transport ProteinsStructure-Activity RelationshipConceptsAmino acid residuesRandom mutagenesisAcid residuesTransport activityCritical amino acid residuesRat brain serotonin transporterCritical residuesTransport cycleWild typeNonconservative mutationsStructural predictionsTransporter functionLater stepsMutationsSerotonin transporterResiduesMutagenesisHydrophobic substitutionsTyr-385TransportersMutantsActivitySubstitutionNearby positionsDetermination of External Loop Topology in the Serotonin Transporter by Site-directed Chemical Labeling*
Chen J, Liu-Chen S, Rudnick G. Determination of External Loop Topology in the Serotonin Transporter by Site-directed Chemical Labeling*. Journal Of Biological Chemistry 1998, 273: 12675-12681. PMID: 9575231, DOI: 10.1074/jbc.273.20.12675.Peer-Reviewed Original ResearchBioenergetics of Neurotransmitter Transport
Rudnick G. Bioenergetics of Neurotransmitter Transport. Journal Of Bioenergetics And Biomembranes 1998, 30: 173-185. PMID: 9672239, DOI: 10.1023/a:1020573325823.Peer-Reviewed Reviews, Practice Guidelines, Standards, and Consensus StatementsConceptsSynaptic vesicle membranePlasma membrane transportersRecycling of neurotransmittersGene familyVesicle lumenPlasma membraneMembrane transportersNeurotransmitter transportersVesicle membraneNeurotransmitter transportVesicular transportersAmino acidsTransportersCoupling stoichiometryDownhill movementCytoplasmEssential componentUphill transportFamilyMembraneEffluxBioenergeticsImportant drugsProteinInflux[16] Ion-coupled neurotransmitter transport: Thermodynamic vs. kinetic determinations of stoichiometry
Rudnick G. [16] Ion-coupled neurotransmitter transport: Thermodynamic vs. kinetic determinations of stoichiometry. Methods In Enzymology 1998, 296: 233-247. PMID: 9779452, DOI: 10.1016/s0076-6879(98)96018-9.Peer-Reviewed Reviews, Practice Guidelines, Standards, and Consensus StatementsConceptsNumber of ionsKinetic determinationMolecular machinesCharge movesIonsLipid bilayersNeurotransmitter moleculesMoleculesInput of energySteady-state distributionLow concentrationsChargeElectrical potentialMembraneIon gradientsStoichiometryHigh concentrationsUltimate concentrationNaConcentrationEnergyBilayersNeurotransmitter transportersNumber of NaNeurotransmitter transport
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 RelationshipTyrosinePlacental biogenic amine transporters: cloning and expression
Padbury J, Tseng Y, McGonnigal B, Penado K, Stephan M, Rudnick G. Placental biogenic amine transporters: cloning and expression. Brain Research 1997, 45: 163-168. PMID: 9105686, DOI: 10.1016/s0169-328x(96)00309-9.Peer-Reviewed Original ResearchMeSH KeywordsAmino Acid SequenceAnimalsBase SequenceBrainCarrier ProteinsCell MembraneCloning, MolecularFemaleHumansMembrane GlycoproteinsMembrane Transport ProteinsMolecular Sequence DataNerve Tissue ProteinsNeuronsPlacentaPregnancyProtein BiosynthesisRecombinant ProteinsSequence Homology, Amino AcidSequence Homology, Nucleic AcidSerotoninSerotonin Plasma Membrane Transport ProteinsSheepAn Extracellular Loop Region of the Serotonin Transporter May Be Involved in the Translocation Mechanism †
Stephan M, Chen M, Penado K, Rudnick G. An Extracellular Loop Region of the Serotonin Transporter May Be Involved in the Translocation Mechanism †. Biochemistry 1997, 36: 1322-1328. PMID: 9063880, DOI: 10.1021/bi962150l.Peer-Reviewed Original ResearchConceptsLarge extracellular loopChimeric transportersWild typeWild type SERTExtracellular loopCocaine analog 2beta-carbomethoxy-3betaCell surface biotinylationWild-type levelsSubstrate translocationExtracellular loop regionSurface biotinylationTranslocation mechanismSerotonin transporterHomologous familyType levelsConformational changesLoop regionRestriction sitesTransportersPoor expressionSubstituted regionsSynaptic cleftDrug bindingSame specificityHigh affinityExternal Cysteine Residues in the Serotonin Transporter †
Chen J, Liu-Chen S, Rudnick G. External Cysteine Residues in the Serotonin Transporter †. Biochemistry 1997, 36: 1479-1486. PMID: 9063896, DOI: 10.1021/bi962256g.Peer-Reviewed Original ResearchConceptsTransport activityMTS reagentsCysteine residuesWild typeWild-type transporterSecond external loopTransient expression systemSurface expressionRat serotonin transporterExternal cysteine residuesHydropathy analysisMutant transportersType transporterDouble mutantExpression systemMethanethiosulfonate reagentsLigand bindingSerotonin transporterMutantsExtracellular loopHeLa cellsDisulfide bondsPartial activityTransportersSerine
1996
Cell-specific Sorting of Biogenic Amine Transporters Expressed in Epithelial Cells*
Gu H, Ahn J, Caplan M, Blakely R, Levey A, Rudnick G. Cell-specific Sorting of Biogenic Amine Transporters Expressed in Epithelial Cells*. Journal Of Biological Chemistry 1996, 271: 18100-18106. PMID: 8663573, DOI: 10.1074/jbc.271.30.18100.Peer-Reviewed Original ResearchMeSH KeywordsAnimalsBiogenic AminesBiological TransportCarrier ProteinsCell CompartmentationCell MembraneCell PolarityCells, CulturedDogsDopamineDopamine Plasma Membrane Transport ProteinsEpithelial CellsHumansImmunohistochemistryMembrane GlycoproteinsMembrane Transport ProteinsNerve Tissue ProteinsNorepinephrineNorepinephrine Plasma Membrane Transport ProteinsRatsRecombinant ProteinsSerotoninSerotonin Plasma Membrane Transport ProteinsSymportersConceptsMadin-Darby canine kidneyMDCK cellsLLC-PK1 cellsNeurotransmitter transportersCell surface biotinylationConfocal immunofluorescence microscopyBasolateral membraneCell-specific mechanismsEpithelial cellsBiogenic amine transportersMembrane proteinsSurface biotinylationCDNA encodingHuman DA transporterAmine transportersImmunofluorescence microscopyBiotinylating reagentTransportersPermeable filter supportsApical surfaceImmunocytochemistry resultsBasolateral mediumSurface expressionApical sideDA transporterPolarized Expression of GABA Transporters in Madin-Darby Canine Kidney Cells and Cultured Hippocampal Neurons (∗)
Ahn J, Mundigl O, Muth T, Rudnick G, Caplan M. Polarized Expression of GABA Transporters in Madin-Darby Canine Kidney Cells and Cultured Hippocampal Neurons (∗). Journal Of Biological Chemistry 1996, 271: 6917-6924. PMID: 8636119, DOI: 10.1074/jbc.271.12.6917.Peer-Reviewed Original ResearchMeSH KeywordsAmino Acid SequenceAnimalsAxonsBase SequenceCarrier ProteinsCell LineDNA PrimersDNA, ComplementaryDogsGABA Plasma Membrane Transport ProteinsGamma-Aminobutyric AcidHippocampusKidneyMembrane ProteinsMembrane Transport ProteinsMicroinjectionsMolecular Sequence DataNeuronsOrganic Anion TransportersConceptsMadin-Darby canine kidney cellsCanine kidney cellsMDCK cellsBetaine transporterMembrane protein sortingAmino acid sequence identityApical membraneCell surface biotinylationGAT-2GABA transporterKidney cellsGamma-aminobutyric acid transporterEpithelial cellsProtein sortingGAT-1Polarized neuronsSurface biotinylationSequence identityAcid transportersCultured hippocampal neuronsHippocampal neuronsPolarized expressionCell typesTransporter GAT-1Basolateral surfaceIon 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