2024
High-resolution yeast actin structures indicate the molecular mechanism of actin filament stiffening by cations
Xu X, Cao W, Swift M, Pandit N, Huehn A, Sindelar C, De La Cruz E, Hanein D, Volkmann N. High-resolution yeast actin structures indicate the molecular mechanism of actin filament stiffening by cations. Communications Chemistry 2024, 7: 164. PMID: 39079963, PMCID: PMC11289367, DOI: 10.1038/s42004-024-01243-x.Peer-Reviewed Original ResearchActin filamentsVertebrate actinsActin structuresDNase I binding loopActin filament assemblyEukaryotic cell functionStructures of wild-typeNear-atomic resolution structuresPotential binding sitesActin subunitsFilament assemblyRegulatory proteinsDNase IA167ActinAdjacent subunitsRegulatory roleMolecular mechanismsVertebratesWild-typeGlutamic acidCell functionFilamentsSubunitResiduesCryo-EM structures reveal how phosphate release from Arp3 weakens actin filament branches formed by Arp2/3 complex
Chavali S, Chou S, Cao W, Pollard T, De La Cruz E, Sindelar C. Cryo-EM structures reveal how phosphate release from Arp3 weakens actin filament branches formed by Arp2/3 complex. Nature Communications 2024, 15: 2059. PMID: 38448439, PMCID: PMC10918085, DOI: 10.1038/s41467-024-46179-x.Peer-Reviewed Original ResearchConceptsArp2/3 complexActin filamentsCryo-EM structureMother filamentDaughter filamentArp2/3 complex nucleates branched actin filamentsActin filament branchingBranched actin filamentsDissociation of PiADP-PiFilament branchingOrganelle movementADP stateBranch junctionsArp3A-resolutionActinArp2/3ADP-BeFxFilamentsADPPhosphate releaseFilament mechanismArp2Organelles
2020
Force and phosphate release from Arp2/3 complex promote dissociation of actin filament branches
Pandit NG, Cao W, Bibeau J, Johnson-Chavarria EM, Taylor EW, Pollard TD, De La Cruz EM. Force and phosphate release from Arp2/3 complex promote dissociation of actin filament branches. Proceedings Of The National Academy Of Sciences Of The United States Of America 2020, 117: 13519-13528. PMID: 32461373, PMCID: PMC7306818, DOI: 10.1073/pnas.1911183117.Peer-Reviewed Original ResearchConceptsActin filament branchesArp2/3 complexMother filamentFilament branchesTotal internal reflection fluorescence microscopyEssential cellular functionsMechanical forcesActin filament networkReflection fluorescence microscopyCellular functionsActin networkCell motilityComplex generatesActin filamentsArp2/3Filament networkFluorescence microscopyState 1Branch junctionsState 2FilamentsComplexesPhosphate releaseMuscle actinADPStructures of cofilin-induced structural changes reveal local and asymmetric perturbations of actin filaments
Huehn AR, Bibeau JP, Schramm AC, Cao W, De La Cruz EM, Sindelar CV. Structures of cofilin-induced structural changes reveal local and asymmetric perturbations of actin filaments. Proceedings Of The National Academy Of Sciences Of The United States Of America 2020, 117: 1478-1484. PMID: 31900364, PMCID: PMC6983403, DOI: 10.1073/pnas.1915987117.Peer-Reviewed Original ResearchConceptsFilament severingActin filamentsSevering activityCofilin/ADF familyActin conformational changesActin filament severingFilament-severing activityCryo-electron microscopy dataSevers actin filamentsWeak severing activityUnique binding modeCofilin clustersActin structuresCofilin bindingCofilin-decorated segmentsCofilinMolecular understandingBarbed endsConformational changesCooperative bindingBinding cooperativityFilament endsPositive cooperativityBinding modesSevering
2018
The actin filament twist changes abruptly at boundaries between bare and cofilin-decorated segments
Huehn A, Cao W, Elam WA, Liu X, De La Cruz EM, Sindelar CV. The actin filament twist changes abruptly at boundaries between bare and cofilin-decorated segments. Journal Of Biological Chemistry 2018, 293: 5377-5383. PMID: 29463680, PMCID: PMC5900768, DOI: 10.1074/jbc.ac118.001843.Peer-Reviewed Original ResearchConceptsCofilin-decorated segmentsConformational changesCofilin/ADF proteinsActin-remodeling proteinsBind actin filamentsActin filament interactionsCofilin-induced changesEffects of cofilinCooperative conformational changesProtein occupancyADF proteinsCellular processesCell divisionStructure-based methodsCryo-EMActin segmentsIntracellular transportActin filamentsFilament twistCooperative bindingCofilinTwist changesActinFluorophore labelingSubunits
2017
Phosphomimetic S3D cofilin binds but only weakly severs actin filaments
Elam WA, Cao W, Kang H, Huehn A, Hocky GM, Prochniewicz E, Schramm AC, Negrón K, Garcia J, Bonello TT, Gunning PW, Thomas DD, Voth GA, Sindelar CV, De La Cruz EM. Phosphomimetic S3D cofilin binds but only weakly severs actin filaments. Journal Of Biological Chemistry 2017, 292: 19565-19579. PMID: 28939776, PMCID: PMC5712599, DOI: 10.1074/jbc.m117.808378.Peer-Reviewed Original ResearchConceptsActin bindingWild-type cofilinActin filament severingHigh cooperativitySubstitution of serineCofilin bindsActin cytoskeletonProtein cofilinCell divisionSer-3Filament severingAtom molecular dynamics simulationsSubunit interactionsN-terminusCofilinBiological processesActin filamentsTime-resolved phosphorescence anisotropyElectron cryomicroscopyRapid remodelingPhosphorylationSeveringFilament mechanical propertiesActin segmentsFilaments
2014
Site-specific cation release drives actin filament severing by vertebrate cofilin
Kang H, Bradley MJ, Cao W, Zhou K, Grintsevich EE, Michelot A, Sindelar CV, Hochstrasser M, De La Cruz EM. Site-specific cation release drives actin filament severing by vertebrate cofilin. Proceedings Of The National Academy Of Sciences Of The United States Of America 2014, 111: 17821-17826. PMID: 25468977, PMCID: PMC4273407, DOI: 10.1073/pnas.1413397111.Peer-Reviewed Original ResearchConceptsFilament severingActin filamentsActin filament severingKey regulatory functionsConcentration of endsActin filament fragmentationEukaryotic cellsCation-binding sitesProtein cofilinDeletion mutantsS. cerevisiaeSubunit exchangeFilament turnoverActin polymerizationEssential functionsSite-specific interactionsCofilinMolecular mechanismsAssembly dynamicsRegulatory functionsActin moleculesFilament fragmentationFilament structureSustained motilitySevering
2011
Actin Filament Dynamics in the Actomyosin VI Complex Is Regulated Allosterically by Calcium–Calmodulin Light Chain
Prochniewicz E, Pierre A, McCullough BR, Chin HF, Cao W, Saunders LP, Thomas DD, De La Cruz EM. Actin Filament Dynamics in the Actomyosin VI Complex Is Regulated Allosterically by Calcium–Calmodulin Light Chain. Journal Of Molecular Biology 2011, 413: 584-592. PMID: 21910998, PMCID: PMC3633491, DOI: 10.1016/j.jmb.2011.08.058.Peer-Reviewed Original ResearchConceptsActin filament dynamicsMyosin VIFilament dynamicsMicrosecond dynamicsCaM-dependent mannerCalmodulin light chainsLight chainActin bindingActin filamentsDependent CaMIQ domainCaM-dependent regulationFluorescence microscopyEnzymatic activityTransient phosphorescence anisotropyATP utilizationFinal anisotropyMicrosecond rotational dynamicsPhosphorescence anisotropyMyosinStructural dynamicsAnisotropy decaySuch modulationActinRegulation