CDKN1A
cyclin dependent kinase inhibitor 1A | CAP20, CIP1, P21, SDI1, WAF1, p21, p21CIP1, p21Cip1/Waf1, CDKN1

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]

Biological processes 93 terms
DNA damage response (GO:0006974)DNA damage response (GO:0006974)DNA damage response (GO:0006974)DNA damage response, signal transduction by p53 class mediator (GO:0030330)DNA damage response, signal transduction by p53 class mediator (GO:0030330)G1/S transition of mitotic cell cycle (GO:0000082)PCNA-p21 complex (GO:0070557)PCNA-p21 complex (GO:0070557)PCNA-p21 complex (GO:0070557)Ras protein signal transduction (GO:0007265)cellular response to UV-B (GO:0071493)cellular response to UV-B (GO:0071493)cellular response to amino acid starvation (GO:0034198)cellular response to amino acid starvation (GO:0034198)cellular response to cell-matrix adhesion (GO:0071460)cellular response to ionizing radiation (GO:0071479)cellular response to ionizing radiation (GO:0071479)cellular senescence (GO:0090398)cellular senescence (GO:0090398)cellular senescence (GO:0090398)cellular senescence (GO:0090398)cyclin binding (GO:0030332)cyclin binding (GO:0030332)cyclin-dependent protein kinase holoenzyme complex (GO:0000307)cyclin-dependent protein kinase holoenzyme complex (GO:0000307)cyclin-dependent protein kinase holoenzyme complex (GO:0000307)cyclin-dependent protein serine/threonine kinase inhibitor activity (GO:0004861)cyclin-dependent protein serine/threonine kinase inhibitor activity (GO:0004861)cyclin-dependent protein serine/threonine kinase inhibitor activity (GO:0004861)cyclin-dependent protein serine/threonine kinase inhibitor activity (GO:0004861)cytoplasm (GO:0005737)cytoplasm (GO:0005737)cytosol (GO:0005829)cytosol (GO:0005829)heart development (GO:0007507)heart development (GO:0007507)import into nucleus (GO:0051170)import into nucleus (GO:0051170)intrinsic apoptotic signaling pathway (GO:0097193)intrinsic apoptotic signaling pathway (GO:0097193)mitotic G1 DNA damage checkpoint signaling (GO:0031571)mitotic G2 DNA damage checkpoint signaling (GO:0007095)molecular function activator activity (GO:0140677)molecular function inhibitor activity (GO:0140678)negative regulation of DNA biosynthetic process (GO:2000279)negative regulation of G1/S transition of mitotic cell cycle (GO:2000134)negative regulation of cardiac muscle tissue regeneration (GO:1905179)negative regulation of cardiac muscle tissue regeneration (GO:1905179)negative regulation of cell growth (GO:0030308)negative regulation of cell population proliferation (GO:0008285)negative regulation of cell population proliferation (GO:0008285)negative regulation of cell population proliferation (GO:0008285)negative regulation of growth (GO:0045926)negative regulation of protein phosphorylation (GO:0001933)negative regulation of vascular associated smooth muscle cell proliferation (GO:1904706)nuclear body (GO:0016604)nucleolus (GO:0005730)nucleoplasm (GO:0005654)nucleoplasm (GO:0005654)nucleus (GO:0005634)nucleus (GO:0005634)nucleus (GO:0005634)positive regulation of DNA replication (GO:0045740)positive regulation of cell population proliferation (GO:0008284)positive regulation of fibroblast proliferation (GO:0048146)positive regulation of protein kinase activity (GO:0045860)positive regulation of protein phosphorylation (GO:0001934)positive regulation of reactive oxygen species metabolic process (GO:2000379)positive regulation of reactive oxygen species metabolic process (GO:2000379)protein binding (GO:0005515)protein kinase binding (GO:0019901)protein kinase inhibitor activity (GO:0004860)protein sequestering activity (GO:0140311)protein sequestering activity (GO:0140311)protein serine/threonine kinase binding (GO:0120283)protein-containing complex (GO:0032991)protein-containing complex binding (GO:0044877)regulation of DNA biosynthetic process (GO:2000278)regulation of G1/S transition of mitotic cell cycle (GO:2000045)regulation of G1/S transition of mitotic cell cycle (GO:2000045)regulation of G2/M transition of mitotic cell cycle (GO:0010389)regulation of cell cycle (GO:0051726)regulation of cell cycle (GO:0051726)regulation of cell cycle (GO:0051726)regulation of cell cycle (GO:0051726)regulation of cell cycle G1/S phase transition (GO:1902806)regulation of mitotic cell cycle (GO:0007346)replicative senescence (GO:0090399)signal transduction by p53 class mediator (GO:0072331)stress-induced premature senescence (GO:0090400)tissue regeneration (GO:0042246)ubiquitin protein ligase binding (GO:0031625)wound healing (GO:0042060)
Expression (TPM)
CDKN1A — as a Regulated Gene

TFs regulating CDKN1A 0 TFs

Transcription factors with Perturb-seq knockdown data for CDKN1A. The Binding column indicates whether any binding evidence exists for this TF–gene pair (ChIP-seq or motif footprint peaks). The Mean coef is the average Perturb-seq regression coefficient across active gRNAs (positive = CDKN1A upregulated upon KD; negative = downregulated). The Outlier column indicates whether this gene is in the top or bottom 5% of all TF knockdown effects.

Data: Effect:
TF Mean coef Binding Outlier TF→Gene link

Elements linked to CDKN1A

Open chromatin peaks (ATAC-seq) in the genomic neighbourhood of CDKN1A, linked by TSS proximity or chromatin conformation (Multiome / HiCAR). Each element overlaps at least one TF ChIP-seq binding site — the TFs column shows how many distinct TFs bind that element.

Accessibility Element Dist. to TSS Link type TFs
chr6:36,667,165–36,667,556 9.0 kb Proximal (<10kb) 821
chr6:36,678,325–36,679,788 1.8 kb Proximal (<10kb) 955
chr6:36,680,517–36,680,717 4.0 kb Proximal (<10kb) 669

Genome Browser

Genomic view of the CDKN1A locus showing ATAC-seq accessibility and RNA-seq expression across the ESC → DE time course, together with TF binding peaks and element-to-TSS loop connections.

chr6:36,657,165 – 36,690,717
Proximal 1 kb Distal 10 kb Multiome HiCAR ATAC-seq RNA-seq