p21 Recombinant Rabbit Monoclonal Antibody [PSH03-93] (HA722065)

UNIPROT #

P39689

PROTEIN NAME

p21

SYNONYMS

CAP20 antibody;CDK-interacting protein 1 antibody;CDKI antibody;CDKN1 antibody;Cdkn1a antibody;CDN1A_HUMAN antibody;CIP1 antibody;Cyclin Dependent Kinase Inhibitor 1A antibody;Cyclin-dependent kinase inhibitor 1 antibody;Cyclin-dependent kinase inhibitor 1A (P21) antibody;Cyclin-dependent kinase inhibitor 1A (p21, Cip1) antibody;DNA Synthesis Inhibitor antibody;MDA-6 antibody;MDA6 antibody;Melanoma differentiation-associated protein 6 antibody;Melanoma differentiation-associated protein antibody;p21 antibody;P21 protein antibody;p21CIP1 antibody;p21Cip1/Waf1 antibody;p21WAF antibody;PIC1 antibody;SDI1 antibody;SLC12A9 antibody;WAF1 antibody;Wild type p53 activated fragment 1 (WAF1) antibody;Wild type p53 activated fragment 1 antibody;Wildtype p53-activated fragment 1 antibody

SUBCELLULAR LOCATION

Cytoplasm, Nucleus.

FUNCTION

p21 is a potent cyclin-dependent kinase inhibitor (CKI). The p21 (CIP1/WAF1) protein binds to and inhibits the activity of cyclin-CDK2, -CDK1, and -CDK4/6 complexes, and thus functions as a regulator of cell cycle progression at G1 and S phase. The binding of p21 to CDK complexes occurs through p21's N-terminal domain, which is homologous to the other CIP/KIP CDK inhibitors p27 and p57. Specifically it contains a Cy1 motif in the N-terminal half, and weaker Cy2 motif in the C-terminal domain that allow it to bind CDK in a region that blocks its ability to complex with cyclins and thus prevent CDK activation. Experiments looking at CDK2 activity within single cells have also shown p21 to be responsible for a bifurcation in CDK2 activity following mitosis, cells with high p21 enter a G0/quiescent state, whilst those with low p21 continue to proliferate. Follow up work, found evidence that this bistability is underpinned by double negative feedback between p21 and CDK2, where CDK2 inhibits p21 activity via ubiquitin ligase activity.