CCNK
Description
The CCNK (cyclin K) is a protein-coding gene located on chromosome 14.
Cyclin-K is a protein encoded by the CCNK gene in humans, belonging to the transcription cyclin family. These cyclins regulate transcription by associating with and activating cyclin-dependent kinases (CDKs) through conformational changes. This activation leads to the formation of kinase complexes that phosphorylate target proteins, ultimately regulating cell cycle progression. Cyclin K has a dual role in regulating both CDK and RNA polymerase II (RNAP2) activities, primarily using RNA recruitment for transcription activation. It interacts with several CDKs, including CDK9, CDK12, and CDK13, aiding in the phosphorylation of RNAP2 subunits' C-terminal domains. Cyclin K is particularly recognized for its association with processive elongation.
Cyclin K acts as a regulatory subunit of cyclin-dependent kinases, promoting the activation of target kinases. It plays a crucial role in transcriptional regulation by modulating the phosphorylation of the C-terminal domain (CTD) of RNA polymerase II's large subunit (POLR2A).
CCNK is also known as CPR4, IDDHDF.
