p21 or p27 protein is able to interact with cyclin-CDK complexes within the nucleus and hence regulate the cell cycle. p21 and p27 are themselves regulated either by sequestration via cyclin-CDK complexes, or by phosphorylation on serine/threonine …

Here, we review disorder-mediated cell cycle regulation by two intrinsically disordered proteins, p21 and p27. A structural adaptation mechanism involving a stretchable, dynamic linker helix allows p21 to promiscuously recognize the various Cdk/cyclin complexes that …

Mar 31, 2022 · Following activation of p53, for example by viral infection or induction of DNA damage, p21 expression is upregulated. High levels of p21 then result in RB-E2F complex formation and...

Following anti-mitogenic signals or DNA damage, p21 and p27 bind to cyclin-CDK complexes to inhibit their catalytic activity and induce cell-cycle arrest. Interestingly, recent discoveries suggest that p21 and p27 might have new activities that are unrelated to their function as CDK inhibitors.

Notably, loss of expression or function of two G1-checkpoint CDK inhibitors – p21 (CDKN1A) and p27 (CDKN1B) – has been implicated in the genesis or progression of many human malignancies. Additionally, there is a growing body of evidence suggesting that functional loss of p21 or p27 can mediate a drug-resistance phenotype.

Our work shows that glandular hyperplasias developed in p21–p27 double-KO mice displayed statistically significant lower values of γH2AX positive-cells when compared with similar lesions in mice lacking either p21 or p27.

Dec 13, 2019 · Mice lacking p21 or p27 are susceptible to tumorigenesis (27, 28), which is consistent with the important roles of CIP and KIP proteins in negatively regulating the cell cycle through CDK2 inhibition. p27 degradation is critical for licensing entry into S phase, and p21 is a key effector of p53-activated senescence (25, 29). p27 directly ...

Jul 1, 2008 · However, reports in the literature have also suggested p21 and p27 can promote tumours, indicating a paradoxical effect. Here, we review historic and recent studies of these two CDK inhibitors, including their identification, function, importance to carcinogenesis and finally their roles in drug resistance.

Sep 1, 2018 · The p27 amino terminal region has 44% similarity with p21, and like p21 this protein inhibits phosphorylation of Rb by cyclins, and as a result prevents separation of E 2 F from Rb, which in total prevents from transcription of genes required for G1/S transition.

Following anti-mitogenic signals or DNA damage, p21 and p27 bind to cyclin–CDK complexes to inhibit their catalytic activity and induce cell-cycle arrest. Interestingly, recent discoveries suggest that p21 and p27 might have new activities that are unrelated to their function as CDK inhibitors.