Cell CycleApoptosisCell Cycle ProteinsS PhaseCell Cycle CheckpointsG1 PhaseDNA DamageG2 PhaseCheckpoint Kinase 2MitosisGenes, cdcProtein-Serine-Threonine KinasesAtaxia Telangiectasia Mutated ProteinsCyclinsRetinoblastoma ProteinG2 Phase Cell Cycle CheckpointsCell LineTumor Suppressor Protein p53Cell DivisionCyclin-Dependent KinasesMammalsPhosphorylationCyclin-Dependent Kinase 2DNA RepairE2F Transcription FactorsProtein KinasesDNA-Binding ProteinsHeLa CellsTumor Suppressor ProteinsNuclear ProteinsCyclin ECyclin-Dependent Kinase Inhibitor p21DNA ReplicationCell Line, TumorModels, BiologicalCDC2-CDC28 KinasesSignal TransductionFibroblastsGamma Rayscdc25 PhosphatasesCDC2 Protein KinaseM Phase Cell Cycle CheckpointsMolecular Sequence DataCells, CulturedMutationCyclin-Dependent Kinase Inhibitor p27Radiation, IonizingHydroxyureaCyclin-Dependent Kinase 4Ataxia TelangiectasiaSpindle ApparatusCell ProliferationG1 Phase Cell Cycle CheckpointsCell SurvivalTranscription FactorsFlow CytometryTumor Cells, CulturedRadiation ToleranceSaccharomyces cerevisiae ProteinsAmino Acid SequenceSaccharomyces cerevisiaeE2F1 Transcription FactorCyclin B1Cell NucleusTranscription Factor DP1Genomic InstabilityDNATransfectionSchizosaccharomycesRetinoblastoma-Binding Protein 1Base SequenceS Phase Cell Cycle CheckpointsNocodazoleUltraviolet RaysRNA, Small InterferingProtein BindingSchizosaccharomyces pombe ProteinsHistonesTime FactorsDNA Breaks, Double-StrandedFungal ProteinsCarrier ProteinsRNA, MessengerGene Expression RegulationEnzyme ActivationCaspasesAntineoplastic AgentsIntracellular Signaling Peptides and ProteinsGenes, p53RNA InterferenceApoptosis Regulatory ProteinsCyclin AChromosomal InstabilityEnzyme InhibitorsProto-Oncogene ProteinsCaspase 3Transcription, GeneticCyclin D1Proto-Oncogene Proteins c-bcl-2Interphase