p27Kip1 Important regulator of cell cycle progression. Inhibits the kinase activity of CDK2 bound to cyclin A, but has little inhibitory activity on CDK2 bound to SPDYA. Involved in G1 arrest. Potent inhibitor of cyclin E- and cyclin A-CDK2 complexes. Forms a complex with cyclin type D-CDK4 complexes and is involved in the assembly, stability, and modulation of CCND1-CDK4 complex activation. Acts either as an inhibitor or an activator of cyclin type D-CDK4 complexes depending on its phosphorylation state and/or stoichometry. Belongs to the CDI family. Expressed in all tissues tested. Highest levels in skeletal muscle, lowest in liver and kidney. Note: This description may include information from UniProtKB.
Protein type: Cell cycle regulation; Inhibitor; Oncoprotein; Protein kinase, regulatory subunit
Chromosomal Location of Human Ortholog: 6 G1|6 65.77 cM
Cellular Component:  cytoplasm; cytosol; endosome; intracellular membrane-bounded organelle; nucleus; protein-containing complex
Molecular Function:  chaperone binding; cyclin binding; cyclin-dependent protein serine/threonine kinase inhibitor activity; Hsp70 protein binding; protein binding; protein kinase binding; protein kinase inhibitor activity; protein phosphatase binding; protein-containing complex binding
Biological Process:  autophagic cell death; cell cycle; cell cycle arrest; cell death; cellular response to antibiotic; cellular response to lithium ion; cellular response to organic cyclic compound; G1/S transition of mitotic cell cycle; heart development; inner ear development; mitotic cell cycle arrest; negative regulation of apoptotic process; negative regulation of cardiac muscle tissue regeneration; negative regulation of cell cycle; negative regulation of cell growth; negative regulation of cell proliferation; negative regulation of cellular component movement; negative regulation of cyclin-dependent protein kinase activity; negative regulation of cyclin-dependent protein serine/threonine kinase activity; negative regulation of epithelial cell proliferation; negative regulation of epithelial cell proliferation involved in prostate gland development; negative regulation of kinase activity; negative regulation of mitotic cell cycle; negative regulation of phosphorylation; negative regulation of transcription, DNA-templated; negative regulation of vascular smooth muscle cell proliferation; Notch signaling pathway; placenta development; positive regulation of cell death; positive regulation of cell proliferation; positive regulation of cyclin-dependent protein serine/threonine kinase activity; positive regulation of microtubule polymerization; potassium ion transport; regulation of cell proliferation; regulation of exit from mitosis; regulation of lens fiber cell differentiation; sensory perception of sound
Reference #:  P46414 (UniProtKB)
Alt. Names/Synonyms: AA408329; AI843786; Cdkn1b; CDN1B; Cyclin-dependent kinase inhibitor 1B; Cyclin-dependent kinase inhibitor p27; Kip1; OTTMUSP00000023376; OTTMUSP00000023377; p27; p27Kip1
Gene Symbols: Cdkn1b
Molecular weight: 22,193 Da
Basal Isoelectric point: 6.54  Predict pI for various phosphorylation states
CST Pathways:  ErbB/HER Signaling  |  G1/S Checkpoint  |  Growth And Differentiation Control by MAPKs  |  PI3K/Akt Signaling
Protein-Specific Antibodies or siRNAs from Cell Signaling Technology® Total Proteins
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Protein Structure Not Found.

Cross-references to other databases:  STRING  |  Reactome  |  BioGPS  |  Pfam  |  Phospho.ELM  |  NetworKIN  |  UniProtKB  |  Entrez-Gene  |  Ensembl Gene