Cyclin-Dependent Kinase 3 (CDK3)

CDK3 is among the least characterized members of the cyclin-dependent kinase family. It partners with cyclin C and has been reported to phosphorylate the retinoblastoma protein, driving quiescent cells from G0 into G1 and supporting cell-cycle re-entry; roles in keratinocyte proliferation and in RNA-related regulation through cyclin C have also been described. Expression is detected in a variety of tissues, and unlike the classical cell-cycle CDKs, CDK3 lacks extensive inhibitor validation. Recombinant CDK3 protein provides a defined reagent for kinase profiling, substrate identification and selectivity testing of pan-CDK inhibitors against this understudied paralog.