Multiple checkpoints in the eukaryotic cell cycle ensure that division occurs only after sufficient growth and faithful DNA replication, and only when favorable conditions exist. Of the many proteins involved in cell cycle control, cyclin-dependent kinases (CDKs) are among the most important. How do CDKs function to control the cell cycle?

Multiple checkpoints in the eukaryotic cell cycle ensure that division occurs only after
sufficient growth and faithful DNA replication, and only when favorable conditions
exist. Of the many proteins involved in cell cycle control, cyclin-dependent kinases
(CDKs) are among the most important. How do CDKs function to control the cell
cycle?
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1 Answer

Answer :

CDKs phosphorylate various protein substrates that are required for cell cycle
progression.
Some of the important substrate proteins that CDKs phosphorylate include
condensin proteins, which are essential for the extensive condensation of mitotic
chromosomes, and lamin proteins, which form a stabilizing network under the
nuclear membrane that assembles during mitosis.
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In order to function, CDKs must interact with members of a separate family of proteins named the cyclins. Do individual cyclins remain associated with the same CDKs throughout the entire cell cycle?

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