Cyclins: the Cell Cycle Clock

Cyclins: the Cell Cycle Clock

Cyclins are regulatory proteins that control a cell's progression through the cell cycle. They work by binding to and activating enzymes called cyclin-dependent kinases (CDKs). Levels of the different cyclins fluctuate throughout the cell cycle:

During a particular cell cycle phase, the active cyclins and CDKs work to promote processes appropriate to that phase (such as DNA replication during S phase) and to inhibit processes that the cell isn't ready for.

Reference:

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