CDKentsyymien

CDKentsyymien is the Finnish term used for cyclin-dependent kinases (CDKs), a family of protein kinases that regulate the cell cycle and transcription in eukaryotic cells. They are serine/threonine kinases that require association with cyclin regulatory subunits to be activated, and their activity is finely controlled by phosphorylation and inhibitor proteins.

Key members include CDK1, CDK2, CDK4, CDK6, CDK7, and CDK9, each paired with specific cyclins to control particular cell cycle transitions or transcriptional processes. For example, CDK4 and CDK6 with cyclin D promote G1 progression toward S phase; CDK2 with cyclin E and cyclin A drives S-phase entry and progression; CDK1 with cyclin B drives the G2/M transition. Other CDKs, such as CDK7 and CDK9, have roles in activating other CDKs and in regulating transcription, respectively.

Regulation of CDK activity involves several layers. Activation occurs when a cyclin binds and the complex is phosphorylated at the activation loop by a CDK-activating kinase (CAK), such as CDK7. Activity is inhibited by CDK inhibitors, including the p21, p27, and p16 families. CDKs are also regulated by phosphorylation at additional sites and by degradation of cyclins during the cell cycle, ensuring orderly progression through each phase.

Clinical relevance of CDKs is well established. Dysregulation of CDKs is associated with cancer and other diseases. Several small-molecule CDK inhibitors have been developed as cancer therapies, with approved agents such as palbociclib, ribociclib, and abemaciclib used in various indications. Ongoing research explores selective inhibition of individual CDKs and their broader roles in transcriptional control.

CDKs are conserved across eukaryotes and underpin fundamental cell cycle and transcriptional programs. The term CDKentsyymien is primarily used in Finnish-language scientific contexts to describe this enzyme family.