Cyclin-dependent kinase inhibitor 1A

Cyclin-dependent kinase inhibitor 1A (CDKN1A), also known as p21, Waf1, or Cip1, is a potent inhibitor of cyclin-dependent kinases (CDKs). It plays a crucial role in regulating cell cycle progression by binding to and inhibiting the activity of cyclin-CDK2 or -CDK4 complexes. This inhibition prevents phosphorylation of key substrates required for cell cycle progression from G1 to S phase. p21/CDKN1A is primarily regulated by the tumor suppressor protein p53. In response to DNA damage or other stress signals that activate p53, CDKN1A expression increases.

Other names

p21Waf1Cip1

CDKN1A inhibits cyclin-CDK complexes, leading to cell cycle arrest. It is primarily regulated by p53 in response to DNA damage or other stress signals.