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Protein Page:
p21Cip1 (human)

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. Note: This description may include information from UniProtKB.
Protein type: Cell cycle regulation; Inhibitor
Chromosomal Location of Human Ortholog: 6p21.2
Cellular Component: cyclin-dependent protein kinase holoenzyme complex; cytosol; nucleolus; nucleoplasm; nucleus; protein complex
Molecular Function: cyclin-dependent protein kinase activating kinase activity; cyclin-dependent protein kinase inhibitor activity; protein binding; 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; response to DNA damage stimulus
Reference #:  P38936 (UniProtKB)
Alt. Names/Synonyms: CAP20; CDK-interacting protein 1; CDK-interaction protein 1; CDKN1; CDKN1A; CDN1A; CIP1; Cyclin-dependent kinase inhibitor 1; cyclin-dependent kinase inhibitor 1A (p21, Cip1); DNA synthesis inhibitor; MDA-6; MDA6; melanoma differentiation associated protein 6; Melanoma differentiation-associated protein 6; p21; p21CIP1; p21Cip1/Waf1; PIC1; SDI1; WAF1; wild-type p53-activated fragment 1
Gene Symbols: CDKN1A
Molecular weight: 18,119 Da
Basal Isoelectric point: 8.69  Predict pI for various phosphorylation states
CST Pathways:  AMPK Signaling  |  G1/S Checkpoint  |  G2/M DNA Damage Checkpoint  |  PI3K/Akt Signaling
Protein-Specific Antibodies or siRNAs from Cell Signaling Technology® Total Proteins
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