Description
p 21W AF1/Cip1/Sdi1/Pic1 is a tumor suppressor protein. Expression of p21WAF1 is induced by wild type, but not mutant, p53 suppressor protein. The p21WAF1 protein binds to cyclin/CDK complexes and inhibits their kinase activity thereby stopping cell cycle progression. It also binds to PCNA (proliferating cell nuclear antigen ) and blocks DNA replication but not the DNA repair process.

