Probable cyclin-dependent protein kinase (CDK) inhibitor that functions as a repressor of mitosis in the endoreduplication cell cycle (PubMed:26546445). Acts as a potent cell cycle inhibitor (PubMed:24399300). Interacts with CDKA-1 and D-type cyclins (PubMed:20706207). Expressed in root meristems after induction. Up-regulated by double-stranded DNA breaks-inducing treatments (PubMed:17227549). Up-regulated by DNA damage (PubMed:24399300).