Acts as a negative regulator of the proliferation of normal cells by interacting strongly with CDK4 and CDK6. This inhibits their ability to interact with cyclins D and to phosphorylate the retinoblastoma protein.
Specificity
Natural and recombinant Rat Cyclin-dependent kinase inhibitor 2A, isoform 1
Heterodimer with CDK4 or CDK6. Predominamt P16 complexes contained CDK6. Interacts with CDK4 (both 'T-172'-phosphorylated and non-phosphorylated forms); the interaction inhibits cyclin D-CDK4 kinase activity. Interacts with ISCO2.