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Domain

The PIP-box K+4 motif mediates both the interaction with PCNA and the recruitment of the DCX(DTL) complex: while the PIP-box interacts with PCNA, the presence of the K+4 submotif, recruits the DCX(DTL) complex, leading to its ubiquitination.

The C-terminal is required for nuclear localization of the cyclin D-CDK4 complex.

Function

Plays an important role in controlling cell cycle progression and DNA damage-induced G2 arrest (PubMed:9106657). Involved in p53/TP53 mediated inhibition of cellular proliferation in response to DNA damage. Also involved in p53-independent DNA damage-induced G2 arrest mediated by CREB3L1 in astrocytes and osteoblasts (By similarity). Binds to and inhibits cyclin-dependent kinase activity, preventing phosphorylation of critical cyclin-dependent kinase substrates and blocking cell cycle progression. Functions in the nuclear localization and assembly of cyclin D-CDK4 complex and promotes its kinase activity towards RB1. At higher stoichiometric ratios, inhibits the kinase activity of the cyclin D-CDK4 complex. Inhibits DNA synthesis by DNA polymerase delta by competing with POLD3 for PCNA binding (PubMed:11595739). Negatively regulates the CDK4- and CDK6-driven phosphorylation of RB1 in keratinocytes, thereby resulting in the release of E2F1 and subsequent transcription of E2F1-driven G1/S phase promoting genes (By similarity).

Post-translational modifications

Phosphorylation of Thr-145 by Akt or of Ser-146 by PKC impairs binding to PCNA. Phosphorylation at Ser-114 by GSK3-beta enhances ubiquitination by the DCX(DTL) complex. Phosphorylation of Thr-145 by PIM2 enhances CDKN1A stability and inhibits cell proliferation. Phosphorylation of Thr-145 by PIM1 results in the relocation of CDKN1A to the cytoplasm and enhanced CDKN1A protein stability. UV radiation-induced phosphorylation at Thr-80 by LKB1 and at Ser-146 by NUAK1 leads to its degradation.

Ubiquitinated by MKRN1; leading to polyubiquitination and 26S proteasome-dependent degradation. Ubiquitinated by the DCX(DTL) complex, also named CRL4(CDT2) complex, leading to its degradation during S phase or following UV irradiation. Ubiquitination by the DCX(DTL) complex is essential to control replication licensing and is PCNA-dependent: interacts with PCNA via its PIP-box, while the presence of the containing the 'K+4' motif in the PIP box, recruit the DCX(DTL) complex, leading to its degradation. Ubiquitination at Ser-2 leads to degradation by the proteasome pathway. Ubiquitinated by RNF114; leading to proteasomal degradation.

Acetylation leads to protein stability. Acetylated in vitro on Lys-141, Lys-154, Lys-161 and Lys-163. Deacetylation by HDAC1 is prevented by competitive binding of C10orf90/FATS to HDAC1 (By similarity).

Sequence similarities

Belongs to the CDI family.

Tissue specificity

Expressed in all adult tissues, with 5-fold lower levels observed in the brain.

Cellular localization

  • Cytoplasm
  • Nucleus

Alternative names

CAP20, CDKN1, CIP1, MDA6, PIC1, SDI1, WAF1, CDKN1A, Cyclin-dependent kinase inhibitor 1, CDK-interacting protein 1, Melanoma differentiation-associated protein 6, p21, MDA-6

Target type

Proteins

Primary research area

Oncology

Other research areas

  • Epigenetics
  • Immuno-oncology

Molecular weight

18119Da

We found 21 products in 5 categories

Primary Antibodies

Assay Kits

Target

Reactive species

Detection method

Proteins & Peptides

Target

Species of origin

Cell Lines & Lysates

Target

Species or organism

Search our catalogue for 'CDKN1A' (21)

Products

ab109520

Anti-p21 antibody [EPR362]

Lab Essentials
Recombinant
RabMAb
KO Validated
20ul selling size

ab109199

Anti-p21 antibody [EPR3993]

Lab Essentials
Recombinant
RabMAb
KO Validated

ab220206

Anti-p21 antibody [CIP1/823]

Lab Essentials
KO Validated

ab218311

Anti-p21 antibody [EPR362] - BSA and Azide free

Recombinant
RabMAb
KO Validated

ab214658

Human p21 ELISA Kit

Recombinant
SimpleStep

ab227443

Anti-p21 antibody

Lab Essentials

ab215971

Anti-p21 antibody [EPR3993] - BSA and Azide free

Recombinant
RabMAb
KO Validated

ab288213

Human CDKN1A knockout A549 cell line

Advanced Validation

ab288200

Human CDKN1A knockout MCF7 cell line

Advanced Validation

ab255349

Human CDKN1A knockout HeLa cell line

Advanced Validation

ab288187

Human CDKN1A knockout HCT116 cell line

Advanced Validation

ab266860

Human CDKN1A knockout HCT116 cell line

Advanced Validation