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 StatementsMeSH KeywordsBinding SitesBiological TransportCarrier ProteinsIon TransportLigandsMembrane Transport ProteinsModels, MolecularProtein Conformation
2011
Cytoplasmic Permeation Pathway of Neurotransmitter Transporters
Rudnick G. Cytoplasmic Permeation Pathway of Neurotransmitter Transporters. Biochemistry 2011, 50: 7462-7475. PMID: 21774491, PMCID: PMC3164596, DOI: 10.1021/bi200926b.Peer-Reviewed Original ResearchConceptsCytoplasmic permeation pathwaysBacterial amino acid transporter LeuTNeurotransmitter transportersPermeation pathwayKingdoms of lifeMammalian serotonin transporterHigh-resolution crystal structuresFour-helix bundleRecent high-resolution crystal structureSubsequent crystal structureStructural repeatsLeuT structureProtein familyCommon structural featuresSolute transportersRelated proteinsLarge structural familyCytoplasmic oneConformational changesSubstrate siteFirst structureBiological membranesTransportersLeuTExtracellular pathways
2009
Ligand Effects on Cross-linking Support a Conformational Mechanism for Serotonin Transport*
Tao Z, Zhang YW, Agyiri A, Rudnick G. Ligand Effects on Cross-linking Support a Conformational Mechanism for Serotonin Transport*. Journal Of Biological Chemistry 2009, 284: 33807-33814. PMID: 19837674, PMCID: PMC2797150, DOI: 10.1074/jbc.m109.071977.Peer-Reviewed Original ResearchConceptsN-terminal cyanogen bromide fragmentGamma-aminobutyric acid transporterCyanogen bromide fragmentsTransmembrane 1Cysteine residuesMutagenesis strategyAcid transportersConformational mechanismSerotonin transportCysteineCorresponding positionDisulfide CrossTransportersSynaptic cleftResiduesSame molecule
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
Permeation 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
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 Research
1997
An 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 affinity
1987
Hydrodynamic properties of the chromaffin granule hydrogen ion pumping adenosinetriphosphatase.
Dean G, Nelson P, Agnew W, Rudnick G. Hydrodynamic properties of the chromaffin granule hydrogen ion pumping adenosinetriphosphatase. Biochemistry 1987, 26: 2301-5. PMID: 2887199, DOI: 10.1021/bi00382a034.Peer-Reviewed Original ResearchMeSH KeywordsAdrenal MedullaAnimalsCattleChromaffin GranulesChromaffin SystemIntracellular MembranesKineticsProtein ConformationProton-Translocating ATPasesConceptsGel permeation chromatographyCm3/Permeation chromatographyHydrodynamic propertiesSedimentation equilibrium centrifugationMixed micellesHydrogen ionsMicellesStokes radiusBovine adrenal chromaffin granulesIntrinsic membrane proteinsDetergentsParticlesParticle volumePropertiesIonsEquilibrium centrifugationChromatographyMitochondrial F1F0-ATPaseAdrenal chromaffin granulesDaltonsProtein componentsMembrane proteinsProtein V