p21 Antibody – Mouse Monoclonal

This gene encodes a potent cyclin-dependent kinase inhibitor. The encoded protein binds to and inhibits the activity of cyclin-cyclin-dependent kinase2 or -cyclin-dependent kinase4 complexes, and thus functions as a regulator of cell cycle progression at G1. The expression of this gene is tightly controlled by the tumor suppressor protein p53, through which this protein mediates the p53-dependent cell cycle G1 phase arrest in response to a variety of stress stimuli. This protein can interact with proliferating cell nuclear antigen, a DNA polymerase accessory factor, and plays a regulatory role in S phase DNA replication and DNA damage repair. This protein was reported to be specifically cleaved by CASP3-like caspases, which thus leads to a dramatic activation of cyclin-dependent kinase2, and may be instrumental in the execution of apoptosis following caspase activation. Mice that lack this gene have the ability to regenerate damaged or missing tissue. Multiple alternatively spliced variants have been found for this gene. [provided by RefSeq, Sep 2015]

p21Cip1: a cell-cycle regulatory protein that Interacts with cyclin-CDK2 and -CDK4, inhibiting cell cycle progression at G1. Its expression is tightly controlled by p53, through which this protein mediates the p53-dependent cell cycle arrest at G1 phase.

Protein type: Cell cycle regulation; Inhibitor

Chromosomal Location of Human Ortholog: 6p21.2

Cellular Component: cyclin-dependent protein kinase holoenzyme complex; cytosol; nuclear body; nucleolus; nucleoplasm; nucleus; protein complex

Molecular Function: cyclin-dependent protein kinase activating kinase activity; cyclin-dependent protein kinase activity; cyclin-dependent protein kinase inhibitor activity; protein binding; protein complex binding; protein kinase binding; protein kinase inhibitor activity; ubiquitin protein ligase binding

Biological Process: cell cycle arrest; cellular response to amino acid starvation; cellular response to extracellular stimulus; DNA damage response, signal transduction by p53 class mediator resulting in cell cycle arrest; G1/S transition of mitotic cell cycle; G2/M transition of mitotic cell cycle; negative regulation of cell growth; negative regulation of cell proliferation; negative regulation of phosphorylation; positive regulation of fibroblast proliferation; positive regulation of protein kinase activity; protein stabilization; Ras protein signal transduction; regulation of cyclin-dependent protein kinase activity; regulation of transcription from RNA polymerase II promoter; response to DNA damage stimulus