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
Structural basis for the clamping and Ca2+ activation of SNARE-mediated fusion by synaptotagmin
Grushin K, Wang J, Coleman J, Rothman JE, Sindelar CV, Krishnakumar SS. Structural basis for the clamping and Ca2+ activation of SNARE-mediated fusion by synaptotagmin. Nature Communications 2019, 10: 2413. PMID: 31160571, PMCID: PMC6546687, DOI: 10.1038/s41467-019-10391-x.Peer-Reviewed Original ResearchConceptsCryo-electron microscopy structureActivation of SNAREsDependent membrane interactionsAnionic lipid headgroupsFusion clampActivator functionSNARE bundleSNARE proteinsMicroscopy structureC2B domainStructural basisSynaptotagmin-1SNAREpinsAliphatic loopsMembrane interactionsComplete assemblyLipid headgroupsLipid membranesNeurotransmitter releaseMembraneKey determinantSynaptotagminSyt1Calcium influxPartial insertionSymmetrical 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
2011
A conformational switch in complexin is required for synaptotagmin to trigger synaptic fusion
Krishnakumar SS, Radoff DT, Kümmel D, Giraudo CG, Li F, Khandan L, Baguley SW, Coleman J, Reinisch KM, Pincet F, Rothman JE. A conformational switch in complexin is required for synaptotagmin to trigger synaptic fusion. Nature Structural & Molecular Biology 2011, 18: 934-940. PMID: 21785412, PMCID: PMC3668341, DOI: 10.1038/nsmb.2103.Peer-Reviewed Original ResearchMeSH KeywordsAdaptor Proteins, Vesicular TransportAmino Acid SequenceAnimalsBinding SitesCrystallography, X-RayHumansMembrane FusionModels, MolecularMolecular Sequence DataMutagenesis, Site-DirectedNerve Tissue ProteinsProtein Structure, TertiaryRatsSynaptosomal-Associated Protein 25SynaptotagminsSyntaxin 1Vesicle-Associated Membrane Protein 2Complexin cross-links prefusion SNAREs into a zigzag array
Kümmel D, Krishnakumar SS, Radoff DT, Li F, Giraudo CG, Pincet F, Rothman JE, Reinisch KM. Complexin cross-links prefusion SNAREs into a zigzag array. Nature Structural & Molecular Biology 2011, 18: 927-933. PMID: 21785414, PMCID: PMC3410656, DOI: 10.1038/nsmb.2101.Peer-Reviewed Original Research