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
Structures 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
Structural basis of the filamin A actin-binding domain interaction with F-actin
Iwamoto DV, Huehn A, Simon B, Huet-Calderwood C, Baldassarre M, Sindelar CV, Calderwood DA. Structural basis of the filamin A actin-binding domain interaction with F-actin. Nature Structural & Molecular Biology 2018, 25: 918-927. PMID: 30224736, PMCID: PMC6173970, DOI: 10.1038/s41594-018-0128-3.Peer-Reviewed Original ResearchConceptsActin-binding domainCalponin homology domainHomology domainF-actinActin cross-linking proteinFunction mutationsTandem calponin homology domainsDisease-associated mutantsCryo-electron microscopyHigh-resolution structuresNumerous genetic diseasesSequence conservationHigher-order structureLinking proteinStructural basisDomain interactionsCell shapeActin filamentsMolecular understandingN-terminalFunctional studiesGenetic diseasesMissense mutationsMutationsAtomic resolutionThe 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 labelingSubunitsHigh-resolution cryo-EM structures of actin-bound myosin states reveal the mechanism of myosin force sensing
Mentes A, Huehn A, Liu X, Zwolak A, Dominguez R, Shuman H, Ostap EM, Sindelar CV. High-resolution cryo-EM structures of actin-bound myosin states reveal the mechanism of myosin force sensing. Proceedings Of The National Academy Of Sciences Of The United States Of America 2018, 115: 1292-1297. PMID: 29358376, PMCID: PMC5819444, DOI: 10.1073/pnas.1718316115.Peer-Reviewed Original ResearchConceptsN-terminal subdomainHigh-resolution cryo-EM structuresADP stateNear-atomic resolution structuresCryo-EM structureCryo-electron microscopyHigh-resolution structuresIsoform-dependent mannerFilamentous actinResolution structureStructural basisMyosin IBActin filamentsStructural diversityRelease pathwayADP releaseActinPointed endPotent stabilizerMyosin
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