Which cyclin/CDK complex is primarily active during the G1-to-S phase transition allowing the cell to commit to DNA replication?
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Correct answer: Cyclin D / CDK4 or CDK6 and Cyclin E / CDK2
Cyclin D–CDK4/6 complexes in early G1 and later Cyclin E–CDK2 complexes near the G1/S boundary phosphorylate targets that allow progression into S phase, committing the cell to DNA replication.
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