P21
- OMIM: 116899
- UniProt: P38936
CDK - inhibitor 1 (also: p21 ) is an inhibitor of cyclin- dependent kinases ( cyclin dependent kinase ), which is essential for the control of the cell cycle in mammals. p21 suppresses cancer growth, among others.
The gene encoding p21 gene in humans is located on chromosome 6 locus p21.2. p21 is regulated mainly at the transcriptional level of cells. Induction of transcription of p21 leads to cell cycle arrest, while the inhibition of transcription leads to different effects, depending on context. p21 knockout mice develop normally until the age of about 16 months. Then they begin to develop tumors.