2020
Synergistic roles of Synaptotagmin-1 and complexin in calcium-regulated neuronal exocytosis
Ramakrishnan S, Bera M, Coleman J, Rothman JE, Krishnakumar SS. Synergistic roles of Synaptotagmin-1 and complexin in calcium-regulated neuronal exocytosis. ELife 2020, 9: e54506. PMID: 32401194, PMCID: PMC7220375, DOI: 10.7554/elife.54506.Peer-Reviewed Original ResearchConceptsSynaptotagmin-1Vesicular fusion machinerySingle-vesicle fusionFusion of vesiclesSNARE complexFusion machineryNeuronal exocytosisOligomer bindsRegulatory proteinsVesicle fusionSNAREpinsSynchronous fusionSynaptic vesiclesNovel mechanismVesiclesComplexinKinetic delayPrimary interfaceSynergistic roleFusionExocytosisMachineryProteinBindsMechanism
2019
Mechanisms of Neurological Dysfunction in GOSR2 Progressive Myoclonus Epilepsy, a Golgi SNAREopathy
Jepson JEC, Praschberger R, Krishnakumar SS. Mechanisms of Neurological Dysfunction in GOSR2 Progressive Myoclonus Epilepsy, a Golgi SNAREopathy. Neuroscience 2019, 420: 41-49. PMID: 30954670, DOI: 10.1016/j.neuroscience.2019.03.057.Peer-Reviewed Original ResearchConceptsEndoplasmic reticulumSNARE proteinsProgressive myoclonus epilepsySecretory trafficking pathwaysCis-Golgi membranesMis-sense mutationsTransport vesiclesGolgi transportTrafficking pathwaysVesicles budSecretory pathwaySuccessive fusion eventsTarget membraneFusion eventsEssential functionsDevelopmental defectsMolecular mechanismsMyoclonus epilepsyProteinFusion stepSevere neurological disordersMutationsMembranePathwayInitial stepMutations in the Neuronal Vesicular SNARE VAMP2 Affect Synaptic Membrane Fusion and Impair Human Neurodevelopment
Salpietro V, Malintan NT, Llano-Rivas I, Spaeth CG, Efthymiou S, Striano P, Vandrovcova J, Cutrupi MC, Chimenz R, David E, Di Rosa G, Marce-Grau A, Raspall-Chaure M, Martin-Hernandez E, Zara F, Minetti C, Study D, Group S, Salpietro V, Efthymiou S, Kriouile Y, Khorassani M, Aguennouz M, Karashova B, Avdjieva D, Kathom H, Tincheva R, Van Maldergem L, Nachbauer W, Boesch S, Arning L, Timmann D, Cormand B, Pérez-Dueñas B, Di Rosa G, Pironti E, Goraya J, Sultan T, Kirmani S, Ibrahim S, Jan F, Mine J, Banu S, Veggiotti P, Ferrari M, Verrotti A, Marseglia G, Savasta S, Garavaglia B, Scuderi C, Borgione E, Dipasquale V, Cutrupi M, Portaro S, Sanchez B, Pineda-Marfa’ M, Munell F, Macaya A, Boles R, Heimer G, Papacostas S, Manole A, Malintan N, Zanetti M, Hanna M, Rothman J, Kullmann D, Houlden H, Bello O, De Zorzi R, Fortuna S, Dauber A, Alkhawaja M, Sultan T, Mankad K, Vitobello A, Thomas Q, Mau-Them F, Faivre L, Martinez-Azorin F, Prada C, Macaya A, Kullmann D, Rothman J, Krishnakumar S, Houlden H. Mutations in the Neuronal Vesicular SNARE VAMP2 Affect Synaptic Membrane Fusion and Impair Human Neurodevelopment. American Journal Of Human Genetics 2019, 104: 721-730. PMID: 30929742, PMCID: PMC6451933, DOI: 10.1016/j.ajhg.2019.02.016.Peer-Reviewed Original ResearchMeSH KeywordsAdolescentAutistic DisorderBrainChildChild, PreschoolEpilepsyExocytosisFemaleHeterozygoteHumansIntellectual DisabilityLipidsMagnetic Resonance ImagingMaleMembrane FusionMovement DisordersMuscle HypotoniaMutationNeurodevelopmental DisordersNeuronsNeurotransmitter AgentsPhenotypeProtein DomainsR-SNARE ProteinsSynapsesVesicle-Associated Membrane Protein 2ConceptsNon-synonymous variantsDe novo mutationsSNARE protein VAMP2Synaptic membrane fusionC-terminal regionNovo mutationsSNARE motifSynaptosomal-associated protein 25C-terminusMembrane fusionVAMP2Vesicle fusionHuman brain developmentAcid deletionSynaptic vesiclesVesicular exocytosisHeterozygous de novo mutationsProtein 25Hyperkinetic movement disordersAdditional neurological featuresHuman neurodevelopmentCentral visual impairmentDisease mechanismsUnrelated individualsMutationsSynaptotagmin oligomers are necessary and can be sufficient to form a Ca2+‐sensitive fusion clamp
Ramakrishnan S, Bera M, Coleman J, Krishnakumar SS, Pincet F, Rothman JE. Synaptotagmin oligomers are necessary and can be sufficient to form a Ca2+‐sensitive fusion clamp. FEBS Letters 2019, 593: 154-162. PMID: 30570144, PMCID: PMC6349546, DOI: 10.1002/1873-3468.13317.Peer-Reviewed Original ResearchSymmetrical organization of proteins under docked synaptic vesicles
Li X, Radhakrishnan A, Grushin K, Kasula R, Chaudhuri A, Gomathinayagam S, Krishnakumar SS, Liu J, Rothman JE. Symmetrical organization of proteins under docked synaptic vesicles. FEBS Letters 2019, 593: 144-153. PMID: 30561792, PMCID: PMC6353562, DOI: 10.1002/1873-3468.13316.Peer-Reviewed Original ResearchConceptsCryo-electron tomography analysisSymmetrical organizationCalcium-regulated exocytosisMunc18 proteinsProtein machineryFusion machinerySingle SNAREpinCircular oligomersMutational analysisRadial positioningSynaptic vesiclesRelease machineryMachinerySynaptotagminProteinRing hypothesisVesiclesObserved arrangementUnderlying mechanismSNAREpinsComplexinNerve growthExocytosisGrowth
2018
Synaptotagmin oligomerization is essential for calcium control of regulated exocytosis
Bello OD, Jouannot O, Chaudhuri A, Stroeva E, Coleman J, Volynski KE, Rothman JE, Krishnakumar SS. Synaptotagmin oligomerization is essential for calcium control of regulated exocytosis. Proceedings Of The National Academy Of Sciences Of The United States Of America 2018, 115: e7624-e7631. PMID: 30038018, PMCID: PMC6094142, DOI: 10.1073/pnas.1808792115.Peer-Reviewed Original ResearchConceptsRegulated exocytosisFusion machineryC2 domain proteinsCore fusion machinerySingle vesicle exocytosisConstitutive exocytosisPrincipal CaVesicular releaseMolecular mechanismsSensitive oligomersExocytosisPheochromocytoma cellsSelective disruptionSpontaneous fusionCritical roleMachineryOligomerizationDirect activationCentral componentStructural featuresConsiderable insightCalcium controlPHluorinSyt1SYTPRRT2 Regulates Synaptic Fusion by Directly Modulating SNARE Complex Assembly
Coleman J, Jouannot O, Ramakrishnan SK, Zanetti MN, Wang J, Salpietro V, Houlden H, Rothman JE, Krishnakumar SS. PRRT2 Regulates Synaptic Fusion by Directly Modulating SNARE Complex Assembly. Cell Reports 2018, 22: 820-831. PMID: 29346777, PMCID: PMC5792450, DOI: 10.1016/j.celrep.2017.12.056.Peer-Reviewed Original ResearchConceptsProline-rich transmembrane protein 2SNARE complex assemblyComplex assemblyTrans-SNARE complex assemblyTerminal proline-rich domainSynaptic SNARE proteinsProline-rich domainParoxysmal neurological disordersSynaptic vesicle primingLive-cell imagingTransmembrane protein 2Synaptic fusionSNARE proteinsVesicle primingSingle exocytotic eventsBiophysical analysisFusion assaysMolecular mechanismsFunction mutationsPhysiological roleExocytotic eventsPre-synaptic terminalsPC12 cellsProtein 2Single vesicles
2017
Mutations in Membrin/GOSR2 Reveal Stringent Secretory Pathway Demands of Dendritic Growth and Synaptic Integrity
Praschberger R, Lowe SA, Malintan NT, Giachello CNG, Patel N, Houlden H, Kullmann DM, Baines RA, Usowicz MM, Krishnakumar SS, Hodge JJL, Rothman JE, Jepson JEC. Mutations in Membrin/GOSR2 Reveal Stringent Secretory Pathway Demands of Dendritic Growth and Synaptic Integrity. Cell Reports 2017, 21: 97-109. PMID: 28978487, PMCID: PMC5640804, DOI: 10.1016/j.celrep.2017.09.004.Peer-Reviewed Original ResearchMeSH KeywordsAnimalsDendritesDrosophila melanogasterFemaleFibroblastsGene ExpressionGenetic Association StudiesGolgi ApparatusHumansMaleMembrane FusionMutationMyoclonic Epilepsies, ProgressivePhenotypePrimary Cell CultureQb-SNARE ProteinsRecombinant ProteinsSaccharomyces cerevisiaeSaccharomyces cerevisiae ProteinsSecretory PathwaySynapsesYoung AdultConceptsMembrane fusionGolgi membrane fusionProgressive myoclonus epilepsyGenotype-phenotype relationshipsPresynaptic cytoskeletonEssential proteinsDrosophila modelMembrinMutationsPathogenic mutationsSynaptic functionProteinMyoclonus epilepsyExplanatory basisCytoskeletonGrowthSynaptic integrityPathway deficitsNervous systemMulti-layered strategySnareFusionFragmentation
2015
Re-visiting the trans insertion model for complexin clamping
Krishnakumar SS, Li F, Coleman J, Schauder CM, Kümmel D, Pincet F, Rothman JE, Reinisch KM. Re-visiting the trans insertion model for complexin clamping. ELife 2015, 4: e04463. PMID: 25831964, PMCID: PMC4384536, DOI: 10.7554/elife.04463.Peer-Reviewed Original ResearchAdaptor Proteins, Vesicular TransportAlgorithmsAnimalsCalorimetryCircular DichroismEntropyFluorescence Resonance Energy TransferHumansKineticsMembrane FusionModels, NeurologicalMutationNerve Tissue ProteinsNeuronsProtein BindingSignal TransductionSNARE ProteinsSynaptic TransmissionSynaptotagminsVesicle-Associated Membrane Protein 2
2013
Conformational Dynamics of Calcium-Triggered Activation of Fusion by Synaptotagmin
Krishnakumar SS, Kümmel D, Jones SJ, Radoff DT, Reinisch KM, Rothman JE. Conformational Dynamics of Calcium-Triggered Activation of Fusion by Synaptotagmin. Biophysical Journal 2013, 105: 2507-2516. PMID: 24314081, PMCID: PMC3853086, DOI: 10.1016/j.bpj.2013.10.029.Peer-Reviewed Original Research
2009
The Effect of Hydrophilic Substitutions and Anionic Lipids upon the Transverse Positioning of the Transmembrane Helix of the ErbB2 (neu) Protein Incorporated into Model Membrane Vesicles
Shahidullah K, Krishnakumar SS, London E. The Effect of Hydrophilic Substitutions and Anionic Lipids upon the Transverse Positioning of the Transmembrane Helix of the ErbB2 (neu) Protein Incorporated into Model Membrane Vesicles. Journal Of Molecular Biology 2009, 396: 209-220. PMID: 19931543, PMCID: PMC2821092, DOI: 10.1016/j.jmb.2009.11.037.Peer-Reviewed Original Research