Cyclin-H (CCNH)

Cyclin-H is a highly conserved regulatory subunit of the cyclin family encoded by the CCNH gene, primarily known for its role in activating cyclin-dependent kinases (CDKs), particularly through formation of the CDK-activating kinase (CAK) complex with CDK7 and MAT1[1][2][6]. This complex is crucial for phosphorylation and activation of other CDKs (such as CDK2 and CDC2) and is indispensable for both cell cycle progression and transcriptional initiation by RNA polymerase II[1][6]. Cyclin-H is ubiquitously expressed, interacts with key regulators including the tumor suppressor p53 and MNAT1, and operates as a pivotal component linking cell division with transcriptional control. Dysregulation of Cyclin-H can contribute to cancer development, as observed in lung carcinoma progression[5]. Despite its critical regulatory role, Cyclin-H itself is not a primary drug target, but its activity is essential for the efficacy of drugs that modulate CDK or CAK complex function.

Other names

Cyclin-HCCNHCycHp34p37MO15-associated proteinCAK complex subunitCDK-activating kinase complex subunitcyclin-dependent kinase-activating kinase complex subunit

For drugs targeting the CAK complex/CDK7/Cyclin-H: inhibition of CDK activation, blocking subsequent cell cycle progression and transcriptional initiation