2000
A Transmembrane Segment Determines the Steady-State Localization of an Ion-Transporting Adenosine Triphosphatase
Dunbar L, Aronson P, Caplan M. A Transmembrane Segment Determines the Steady-State Localization of an Ion-Transporting Adenosine Triphosphatase. Journal Of Cell Biology 2000, 148: 769-778. PMID: 10684257, PMCID: PMC2169368, DOI: 10.1083/jcb.148.4.769.Peer-Reviewed Original ResearchMeSH KeywordsAmino Acid SequenceAnimalsBiological TransportCationsCell LineCell MembraneCell PolarityGlycosphingolipidsGlycosylphosphatidylinositolsH(+)-K(+)-Exchanging ATPaseHydrogen-Ion ConcentrationMembrane ProteinsMolecular Sequence DataOuabainParietal Cells, GastricProtein Sorting SignalsRecombinant Fusion ProteinsSequence AlignmentSequence DeletionSodium-Potassium-Exchanging ATPaseSolubilityTransfectionConceptsK-ATPase alpha subunitAlpha subunitTransmembrane domainPolytopic membrane transport proteinK-ATPaseApical distributionGlycosphingolipid-rich membrane domainsDetergent-insoluble complexesMembrane transport proteinsApical membrane proteinsApical plasma membraneK-ATPase alphaFourth transmembrane domainLocalization signalChimeric pumpsFourth transmembraneTransmembrane segmentsK-ATPase sequencesMembrane compartmentsMembrane domainsMembrane proteinsSequence domainsPlasma membraneGastric parietal cellsTransport proteinsResidues of the Fourth Transmembrane Segments of the Na,K-ATPase and the Gastric H,K-ATPase Contribute to Cation Selectivity*
Mense M, Dunbar L, Blostein R, Caplan M. Residues of the Fourth Transmembrane Segments of the Na,K-ATPase and the Gastric H,K-ATPase Contribute to Cation Selectivity*. Journal Of Biological Chemistry 2000, 275: 1749-1756. PMID: 10636871, DOI: 10.1074/jbc.275.3.1749.Peer-Reviewed Original ResearchMeSH KeywordsAdenosine TriphosphatasesAmino Acid SequenceAnimalsCationsElectrophysiologyH(+)-K(+)-Exchanging ATPaseHydrogen-Ion ConcentrationInhibitory Concentration 50KineticsMolecular Sequence DataMutationOuabainPotassiumRecombinant Fusion ProteinsSequence Homology, Amino AcidSodiumSodium-Potassium-Exchanging ATPaseStomachVanadatesXenopus laevisConceptsFourth transmembrane segmentTransmembrane segmentsATPase assaysK-ATPaseHelical wheel analysisTwo-electrode voltage-clamp experimentsCation selectivityProtein chimerasXenopus laevis oocytesVanadate sensitivityWild-type NaGastric HK-ATPasesXenopus oocytesLaevis oocytesATPase activityAbsence of sodiumResiduesTM4K counterpartsControl constructsOocytesConformational equilibriumAssaysImportant role
1998
Conformational alterations resulting from mutations in cytoplasmic domains of the alpha subunit of the Na,K-ATPase.
Blostein R, Daly SE, Boxenbaum N, Lane LK, Arguello JM, Lingrel JB, Karlish SJ, Caplan MJ, Dunbar L. Conformational alterations resulting from mutations in cytoplasmic domains of the alpha subunit of the Na,K-ATPase. Acta Physiologica Scandinavica. Supplementum 1998, 643: 275-81. PMID: 9789570.Peer-Reviewed Original ResearchConceptsM2-M3 loopCytoplasmic domainCytoplasmic loopK-ATPaseN-terminusStructure/function analysisTransmembrane segment M2Amino-terminal halfMajor cytoplasmic loopFifth transmembrane segmentFirst cytoplasmic loopCatalytic phosphorylation siteMajor conformational statesLow catalytic turnoverPutative cationCytoplasmic mutantsTransmembrane segmentsPhosphorylation sitesTransmembrane domainAlpha 1 subunitSegment M2Cytoplasmic regionApparent affinityAmino terminusTerminal half