1G1/S transition PhaseCheckpointG1/S transition CyclinDependent KinasesG2 Phase-M phasecakeCell cycle DNA replication genespuorigin recognition complexCyclin EsDNA replicationbCyclin DsTTTCC/GCGCG1 PhaseDegradationppuCyclinDE2fpdp1pDNA polymerasesbinactiveG1 CyclinDependant Cyclasesphosphorylation of proteinsinvolved in G1/S transitionRbuepG1/S Cell CycleCDK4ORC2LCCND2MCM4CDKN1AORC1LE2F3CDK7E2F6CREB3L4CCNHTP53RB1E2F2CCNB1MCM6CCND1CDK6ORC3LCREB1CREBL1E2fCDKN1BORC6LPOLEMNAT1CDK7ATMTFDP2TFDP1E2fCDKN2CCCNE2CDC25ARBL1CREB3L3MCM7CDK6ORC5LCREB3E2F1E2F4CCNE1RPA1PRIM2ACDKTFDP1CDKRPA2ORC4LCDK2CCNG2GADD45ACDKN1CRB1CCNE1WEE1RPA3MCM2MYT1MCM5RB1TP53CDC2AMCM3POLE2PRIM1MDM2CCNA1CDK1MYCCDKN2BCDC45LCCND3E2F5CDKN2DCDK4PCNACREB3L1CCNE1CDKN2APOLA2CdKCyclinDCdK