Checkpoint Kinase 2Protein-Serine-Threonine KinasesCell CycleCell Cycle ProteinsDNA DamageCell Cycle CheckpointsG2 PhaseProtein KinasesAtaxia Telangiectasia Mutated ProteinsGenes, cdcS PhaseMitosisG2 Phase Cell Cycle CheckpointsG1 PhasePhosphorylationcdc25 PhosphatasesTumor Suppressor Protein p53Tumor Suppressor ProteinsDNA RepairDNA-Binding ProteinsCDC2 Protein KinaseDNA ReplicationNuclear ProteinsHydroxyureaCyclinsM Phase Cell Cycle CheckpointsCell DivisionCyclin-Dependent Kinase Inhibitor p21ApoptosisRadiation, IonizingMutationSaccharomyces cerevisiae ProteinsGamma RaysCell Line, TumorCyclin BSpindle ApparatusSchizosaccharomycesSignal TransductionSchizosaccharomyces pombe ProteinsCell LineSaccharomyces cerevisiaeAtaxia TelangiectasiaProtein Kinase InhibitorsHeLa CellsRadiation ToleranceS Phase Cell Cycle CheckpointsGenomic InstabilityG1 Phase Cell Cycle CheckpointsMolecular Sequence DataIntracellular Signaling Peptides and ProteinsPhosphatidylinositol 3-KinasesModels, BiologicalUltraviolet RaysCell ProliferationRetinoblastoma ProteinCyclin-Dependent Kinase 2NocodazoleHistonesDNA Breaks, Double-StrandedFibroblastsCyclin B1Protein BindingCyclin-Dependent KinasesFlow CytometryCDC2-CDC28 KinasesCell NucleusFungal ProteinsRNA, Small InterferingTumor Cells, CulturedMAP Kinase Signaling SystemCell SurvivalAmino Acid SequenceDNACyclin-Dependent Kinase Inhibitor p27Enzyme ActivationCells, CulturedBlotting, WesternMethyl MethanesulfonateCyclin ETransfectionBRCA1 ProteinBase SequenceTime FactorsProtein-Tyrosine KinasesRNA InterferenceAntineoplastic AgentsKinetochoresCyclin ATranscription FactorsChromosomal InstabilityEnzyme InhibitorsCyclin-Dependent Kinase 4Gene Expression RegulationCarrier ProteinsNucleic Acid Synthesis InhibitorsMenstrual CycleHCT116 CellsProto-Oncogene ProteinsDNA, FungalRNA, Messenger