Cyclin-dependent kinase (CDK) Activating Kinase (CAK) is involved in activation and phosphorylation of CDK1, CDK2, CDK4 and CDK6 and regulation of the cell cycle. It is required for cell cycle progression and it could be a target for cancer therapy. CAK plays a central role in regulation of messenger RNA synthesis by either inhibition of RNA polymerase II-catalyzed transcription or stimulation of transcription through association with basal transcription repair factor IIH. Phosphorylation by the CDK-activating kinase (CAK) is required for the activation of cyclin-dependent kinases.
