CDK12Cyclin

CDK12Cyclin refers to a complex formed between Cyclin-Dependent Kinase 12 (CDK12) and its regulatory cyclin partners. CDK12 is a member of the cyclin-dependent kinase family, a group of serine/threonine protein kinases essential for cell cycle control and transcription. While CDK12 can associate with several different cyclins, its most prominent partners are members of the Cyclin K family. This CDK12-Cyclin K complex plays a critical role in regulating gene transcription, particularly for genes involved in DNA repair and replication.

The primary function attributed to the CDK12-Cyclin complex is its involvement in the phosphorylation of the C-terminal domain (CTD) of RNA polymerase II. This phosphorylation event is crucial for the proper elongation of RNA transcripts and is particularly important for the production of long non-coding RNAs and genes with complex transcriptional regulation, such as those involved in the DNA damage response. Dysregulation or loss of CDK12 function has been linked to genomic instability, impaired DNA repair mechanisms, and has been observed in various cancers, suggesting its importance as a tumor suppressor or in maintaining genome integrity. Research into the CDK12-Cyclin complex continues to elucidate its precise roles in cellular processes and its potential as a therapeutic target.