2018
Striatal Signaling Regulated by the H3R Histamine Receptor in a Mouse Model of tic Pathophysiology
Rapanelli M, Frick L, Jindachomthong K, Xu J, Ohtsu H, Nairn A, Pittenger C. Striatal Signaling Regulated by the H3R Histamine Receptor in a Mouse Model of tic Pathophysiology. Neuroscience 2018, 392: 172-179. PMID: 30278251, PMCID: PMC6204318, DOI: 10.1016/j.neuroscience.2018.09.035.Peer-Reviewed Original ResearchConceptsHDC-KO miceMitogen-activated protein kinaseHistamine receptorsWT animalsDorsal striatumH3R activationTic-like movementsStriatonigral medium spiny neuronsAkt phosphorylationMedium spiny neuronsWild-type miceRare genetic causeHistamine dysregulationAgonist treatmentKO miceSpiny neuronsTic disordersTic pathophysiologyStriatal signalingMouse modelNeuropsychiatric diseasesKO modelRepetitive movementsStriatumMice
2016
Inhibition of STEP61 ameliorates deficits in mouse and hiPSC-based schizophrenia models
Xu J, Hartley BJ, Kurup P, Phillips A, Topol A, Xu M, Ononenyi C, Foscue E, Ho SM, Baguley TD, Carty N, Barros CS, Müller U, Gupta S, Gochman P, Rapoport J, Ellman JA, Pittenger C, Aronow B, Nairn AC, Nestor MW, Lombroso PJ, Brennand KJ. Inhibition of STEP61 ameliorates deficits in mouse and hiPSC-based schizophrenia models. Molecular Psychiatry 2016, 23: 271-281. PMID: 27752082, PMCID: PMC5395367, DOI: 10.1038/mp.2016.163.Peer-Reviewed Original ResearchConceptsBrain-specific tyrosine phosphataseDephosphorylation of GluN2BExtracellular signal-regulated kinase 1/2Signal-regulated kinase 1/2Glutamate receptor internalizationPluripotent stem cellsKnockout mouse modelTyrosine phosphataseMouse modelKinase 1/2Receptor internalizationImportant regulatorGenetic reductionLoss of NMDARsStem cellsN-methyl DPharmacological inhibitionProtein levelsSynaptic functionSTEP61Patient cohortForebrain neuronsBehavioral deficitsExcitatory neuronsSchizophrenia model
2015
Striatal‐enriched protein tyrosine phosphatase regulates the PTPα/Fyn signaling pathway
Xu J, Kurup P, Foscue E, Lombroso PJ. Striatal‐enriched protein tyrosine phosphatase regulates the PTPα/Fyn signaling pathway. Journal Of Neurochemistry 2015, 134: 629-641. PMID: 25951993, PMCID: PMC4516628, DOI: 10.1111/jnc.13160.Peer-Reviewed Original ResearchConceptsProtein tyrosine phosphataseProtein kinase ARegulation of FynTyrosine phosphataseReceptor-type protein tyrosine phosphatase alphaProtein tyrosine phosphatase alphaStriatal-enriched protein tyrosine phosphataseRegulatory tyrosine residuesActivation of FynTyrosine kinase FynRegulatory tyrosineProtein tyrosinePTPαKinase FynSynaptic membranesKinase ATyrosine residuesFyn activityFynNovel substratePrimary neuronal culturesSTEP61Synergistic regulationMolecular techniquesNovel mechanismSTEP61 is a substrate of the E3 ligase parkin and is upregulated in Parkinson’s disease
Kurup PK, Xu J, Videira RA, Ononenyi C, Baltazar G, Lombroso PJ, Nairn AC. STEP61 is a substrate of the E3 ligase parkin and is upregulated in Parkinson’s disease. Proceedings Of The National Academy Of Sciences Of The United States Of America 2015, 112: 1202-1207. PMID: 25583483, PMCID: PMC4313846, DOI: 10.1073/pnas.1417423112.Peer-Reviewed Original ResearchMeSH KeywordsAnimalsCorpus StriatumCyclic AMP Response Element-Binding ProteinDown-RegulationGene Expression Regulation, EnzymologicHEK293 CellsHumansMAP Kinase Signaling SystemMiceMice, KnockoutMitogen-Activated Protein Kinase 3MPTP PoisoningProtein Tyrosine Phosphatases, Non-ReceptorRatsRats, Sprague-DawleyUbiquitinationUbiquitin-Protein LigasesUp-RegulationConceptsE3 ubiquitin ligase ParkinSubstantia nigra pars compactaPathophysiology of PDProtein tyrosine phosphataseUbiquitin ligase ParkinSporadic Parkinson's diseaseE3 ligase ParkinRegulation of ParkinParkinson's diseaseTyrosine phosphataseParkin mutantsE3 ligaseProteasome systemDopaminergic neuronsDownstream targetsAutosomal recessive juvenile parkinsonismNovel substrateSTEP61ParkinCellular modelSTEP61 levelsSNc dopaminergic neuronsProtein levelsFunction contributesERK1/2
2014
Inhibitor of the Tyrosine Phosphatase STEP Reverses Cognitive Deficits in a Mouse Model of Alzheimer's Disease
Xu J, Chatterjee M, Baguley TD, Brouillette J, Kurup P, Ghosh D, Kanyo J, Zhang Y, Seyb K, Ononenyi C, Foscue E, Anderson GM, Gresack J, Cuny GD, Glicksman MA, Greengard P, Lam TT, Tautz L, Nairn AC, Ellman JA, Lombroso PJ. Inhibitor of the Tyrosine Phosphatase STEP Reverses Cognitive Deficits in a Mouse Model of Alzheimer's Disease. PLOS Biology 2014, 12: e1001923. PMID: 25093460, PMCID: PMC4122355, DOI: 10.1371/journal.pbio.1001923.Peer-Reviewed Original ResearchMeSH KeywordsAlzheimer DiseaseAmino Acid SequenceAnimalsBenzothiepinsCatalytic DomainCell DeathCerebral CortexCognition DisordersCysteineDisease Models, AnimalEnzyme InhibitorsHigh-Throughput Screening AssaysHumansMaleMice, Inbred C57BLMice, KnockoutMolecular Sequence DataNeuronsPhosphorylationPhosphotyrosineProtein Tyrosine Phosphatases, Non-ReceptorSubstrate SpecificityConceptsInhibitors of stepsSpecificity of inhibitorsIsoxazolepropionic acid receptor (AMPAR) traffickingCatalytic cysteinePTP inhibitorsTyrosine phosphataseTyrosine phosphorylationSecondary assaysSTEP KO miceReceptor traffickingFirst large-scale effortN-methyl-D-aspartate receptorsPyk2 activitySTEP inhibitorLarge-scale effortsNovel therapeutic targetSynaptic functionAlzheimer's diseaseNeurodegenerative disordersCortical cellsTherapeutic targetERK1/2Specificity experimentsPhosphataseInhibitors
2012
The tyrosine phosphatase STEP: implications in schizophrenia and the molecular mechanism underlying antipsychotic medications
Carty NC, Xu J, Kurup P, Brouillette J, Goebel-Goody SM, Austin DR, Yuan P, Chen G, Correa PR, Haroutunian V, Pittenger C, Lombroso PJ. The tyrosine phosphatase STEP: implications in schizophrenia and the molecular mechanism underlying antipsychotic medications. Translational Psychiatry 2012, 2: e137-e137. PMID: 22781170, PMCID: PMC3410627, DOI: 10.1038/tp.2012.63.Peer-Reviewed Original ResearchConceptsN-methyl-D-aspartate receptorsSTEP61 levelsSurface expressionPostmortem anterior cingulate cortexGluN2B-containing N-methyl-D-aspartate receptorsGluN1/GluN2B receptorsMK-801 treatmentPathophysiology of schizophreniaAnterior cingulate cortexSTEP knockout miceDorsolateral prefrontal cortexChronic administrationChronic treatmentNeuroleptic treatmentAntipsychotic medicationGlutamatergic functionMK-801Glutamate hypothesisMedications resultsTyrosine phosphatase STEPGlutamatergic signalingKnockout miceGluN2B receptorsCingulate cortexSynaptic plasticityStriatal-enriched Protein-tyrosine Phosphatase (STEP) Regulates Pyk2 Kinase Activity*
Xu J, Kurup P, Bartos JA, Patriarchi T, Hell JW, Lombroso PJ. Striatal-enriched Protein-tyrosine Phosphatase (STEP) Regulates Pyk2 Kinase Activity*. Journal Of Biological Chemistry 2012, 287: 20942-20956. PMID: 22544749, PMCID: PMC3375518, DOI: 10.1074/jbc.m112.368654.Peer-Reviewed Original ResearchConceptsStriatal-enriched protein tyrosine phosphataseProtein tyrosine phosphataseN-Methyl-d-aspartate (NMDA) Receptor TraffickingFocal adhesion kinase familyPyk2 activationProline-rich tyrosine kinase 2Pyk2 kinase activityTyrosine kinase 2Kinase familyKinase membersCytoskeletal reorganizationDiverse functionsKinase activitySTEP KO miceReceptor traffickingKinase 2Tyrosine sitesPyk2 activityEnhanced phosphorylationCell adhesionPyk2PhosphorylationFunctional studiesHematopoietic cellsPostsynaptic density
2011
Reduced levels of the tyrosine phosphatase STEP block beta amyloid‐mediated GluA1/GluA2 receptor internalization
Zhang Y, Kurup P, Xu J, Anderson GM, Greengard P, Nairn AC, Lombroso PJ. Reduced levels of the tyrosine phosphatase STEP block beta amyloid‐mediated GluA1/GluA2 receptor internalization. Journal Of Neurochemistry 2011, 119: 664-672. PMID: 21883219, PMCID: PMC3192910, DOI: 10.1111/j.1471-4159.2011.07450.x.Peer-Reviewed Original ResearchConceptsAD mouse modelMouse modelTriple transgenic AD mouse modelAlzheimer's diseaseTransgenic AD mouse modelGluA2 receptorsAD prefrontal cortexElevated levelsGluA1/GluA2Cortical culturesBeta amyloidRegulate surface expressionCognitive deficitsStriatal-enriched protein tyrosine phosphatasePrefrontal cortexΑ-aminoReceptorsReceptor internalizationSurface expressionReduced levelsReceptor complexCortexDiseaseMiceAβ
2010
Aβ-Mediated NMDA Receptor Endocytosis in Alzheimer's Disease Involves Ubiquitination of the Tyrosine Phosphatase STEP61
Kurup P, Zhang Y, Xu J, Venkitaramani DV, Haroutunian V, Greengard P, Nairn AC, Lombroso PJ. Aβ-Mediated NMDA Receptor Endocytosis in Alzheimer's Disease Involves Ubiquitination of the Tyrosine Phosphatase STEP61. Journal Of Neuroscience 2010, 30: 5948-5957. PMID: 20427654, PMCID: PMC2868326, DOI: 10.1523/jneurosci.0157-10.2010.Peer-Reviewed Original ResearchMeSH KeywordsAgedAged, 80 and overAlzheimer DiseaseAmyloid beta-PeptidesAnimalsCell LineCells, CulturedCerebral CortexEndocytosisHumansIn Vitro TechniquesMiceMice, KnockoutMice, TransgenicMiddle AgedNeuronsProtein Tyrosine Phosphatases, Non-ReceptorRatsRats, Sprague-DawleyReceptors, N-Methyl-D-AspartateUbiquitinated ProteinsUbiquitinationConceptsAlzheimer's diseaseAbeta treatmentNR2B subunitProtein tyrosine Phosphatase 61Cognitive deficitsNMDA receptor internalizationHuman AD brainsMouse cortical culturesNR1/NR2B receptorsNMDA receptor endocytosisIonotropic glutamate receptorsTyrosine phosphatase STEP61AD brainCortical slicesCortical culturesGlutamate receptorsNR2B receptorsPostsynaptic terminalsPrefrontal cortexNeuronal membranesElevated levelsCortexReceptor internalizationUbiquitin-proteasome systemStep activity
2009
Extrasynaptic NMDA Receptors Couple Preferentially to Excitotoxicity via Calpain-Mediated Cleavage of STEP
Xu J, Kurup P, Zhang Y, Goebel-Goody SM, Wu PH, Hawasli AH, Baum ML, Bibb JA, Lombroso PJ. Extrasynaptic NMDA Receptors Couple Preferentially to Excitotoxicity via Calpain-Mediated Cleavage of STEP. Journal Of Neuroscience 2009, 29: 9330-9343. PMID: 19625523, PMCID: PMC2737362, DOI: 10.1523/jneurosci.2212-09.2009.Peer-Reviewed Original ResearchMeSH KeywordsAlternative SplicingAnimalsBrainCalpainCell DeathCells, CulturedCyclin-Dependent Kinase 5EndocytosisGlutamic AcidIn Vitro TechniquesMiceMice, KnockoutMitogen-Activated Protein Kinase 1Mitogen-Activated Protein Kinase 3NeuronsP38 Mitogen-Activated Protein KinasesProtein Tyrosine Phosphatases, Non-ReceptorRatsRats, Sprague-DawleyReceptors, N-Methyl-D-AspartateSynapsesConceptsStriatal-enriched protein tyrosine phosphataseCalpain cleavage sitesP38 activationCell deathCleavage siteExtracellular signal-regulated kinase 1/2Protein tyrosine phosphataseSignal-regulated kinase 1/2Promotes cell survivalActivation of p38Tyrosine phosphataseSubstrate bindingKinase 1/2ERK1/2 activationCalpain cleavageCell survivalNovel mechanismCalpain-mediated proteolysisReceptors coupleP38NMDAR stimulationPostsynaptic terminalsValid targetCleavage productsSTEP substrates