Introduction
An intricate network of cyclin-dependent kinases (CDKs) are organized in a pathway to ensure that each cell accurately replicates its DNA and segregate it equally between the two daughter cells. One CDK–the CDK7 complex–cannot be so easily classified. CDK7 is both a CDK-activating kinase (CAK), which phosphorylates cell-cycle CDKs within the activation segment (T-loop), and a component of the general transcription factor TFIIH, which phosphorylates the C-terminal domain (CTD) of the largest subunit of Pol II. A proposed mode of CDK7 inhibition is the phosphorylation of cyclin H by CDK7 itself or by another kinase.
Read more about this topic: CDK7 Pathway
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