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Anti-p21 antibody [EPR3993] ab109199 is a rabbit monoclonal antibody that is used in p21 western blotting. Suitable for human, mouse and rat samples.

- Recombinant format for unrivaled batch-batch consistency: no need for same-lot requests
- Specificity confirmed with CDKN1A knockout cell line validation
- Antibody clone EPR3993 is cited in over 360 publications


Images

Western blot - Anti-p21 antibody [EPR3993] (AB109199), expandable thumbnail
  • Western blot - Anti-p21 antibody [EPR3993] (AB109199), expandable thumbnail
  • Western blot - Anti-p21 antibody [EPR3993] (AB109199), expandable thumbnail
  • Western blot - Anti-p21 antibody [EPR3993] (AB109199), expandable thumbnail
  • Western blot - Anti-p21 antibody [EPR3993] (AB109199), expandable thumbnail

Publications

Key facts

Isotype

IgG

Host species

Rabbit

Storage buffer

pH: 7.2 - 7.4
Preservative: 0.01% Sodium azide
Constituents: 59% PBS, 40% Glycerol (glycerin, glycerine), 0.05% BSA

Form

Liquid

Clonality

Monoclonal

Immunogen

  • The exact immunogen used to generate this antibody is proprietary information.

Reactivity data

Select an application
Product promiseTestedExpectedPredictedNot recommended
WB
Human
Tested
Mouse
Tested
Rat
Tested

Tested
Tested

Species

Mouse

Dilution info

1/1000

Notes

For unpurified use at 1/1000 - 1/10000. Not recommended for use with tissue samples.

Species

Rat

Dilution info

1/1000

Notes

For unpurified use at 1/1000 - 1/10000. Not recommended for use with tissue samples.

Species

Human

Dilution info

1/1000

Notes

For unpurified use at 1/1000 - 1/10000. Not recommended for use with tissue samples.

Associated Products

Select an associated product type

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Target data

Function

May be involved in p53/TP53 mediated inhibition of cellular proliferation in response to DNA damage. 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). Plays an important role in controlling cell cycle progression and DNA damage-induced G2 arrest (PubMed:9106657).

Alternative names

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

Recommended products

Anti-p21 antibody [EPR3993] ab109199 is a rabbit monoclonal antibody that is used in p21 western blotting. Suitable for human, mouse and rat samples.

- Recombinant format for unrivaled batch-batch consistency: no need for same-lot requests
- Specificity confirmed with CDKN1A knockout cell line validation
- Antibody clone EPR3993 is cited in over 360 publications

Key facts

Isotype

IgG

Form

Liquid

Clonality

Monoclonal

Immunogen
  • The exact immunogen used to generate this antibody is proprietary information.
Clone number

EPR3993

Purification technique

Affinity purification Protein A

Specificity

Expression levels of the target protein vary between different tissue/cell lines and in some cases, induction may be required before a signal is observed.
This antibody is not recommended for use in WB with tissue and primary cell samples.
We recommended ab109520 and ab188224 for use in IHC.

Concentration
Loading...

Storage

Shipped at conditions

Blue Ice

Appropriate short-term storage duration

1-2 weeks

Appropriate short-term storage conditions

+4°C

Appropriate long-term storage conditions

-20°C

Aliquoting information

Upon delivery aliquot

Storage information

Stable for 12 months at -20°C

Notes

Our RabMAb® technology is a patented hybridoma-based technology for making rabbit monoclonal antibodies. For details on our patents, please refer to RabMAb® patents.

This product is a recombinant monoclonal antibody, which offers several advantages including:

  • - High batch-to-batch consistency and reproducibility
  • - Improved sensitivity and specificity
  • - Long-term security of supply
  • - Animal-free batch production

For more information, read more on recombinant antibodies.

Supplementary info

This supplementary information is collated from multiple sources and compiled automatically.

Activity summary

The p21 protein also known as CDKN1A is an important regulator of cell cycle progression. It acts as a cyclin-dependent kinase inhibitor where it binds to and inhibits the activity of cyclin-CDK2 or -CDK4 complexes. The molecular weight of p21 is approximately 21 kDa. Cellular expression of p21 is diverse; it occurs in various tissues reflecting its broad role in maintaining cell cycle control. This protein's expression level is often assessed using techniques such as p21 western blotting p21 ELISA and p21 IHC staining.

Biological function summary

P21 plays a critical role in cell cycle regulation and DNA damage response. It associates with the p53 tumor suppressor protein forming an essential part of the p53 signaling pathway under stress conditions. p21 arrests cells in G1 phase allowing DNA repair or leading to cellular senescence. Through these mechanisms p21 integrates signals from stress and damage emphasizing its importance as a mediator in cellular checkpoint control.

Pathways

P21 is closely involved in the p53 and the Transforming Growth Factor-beta (TGF-β) signaling pathways. This integration helps in transmitting growth-inhibitory signals. p21 interacts with proteins such as p53 and cyclins ensuring precise regulation of the cell cycle and growth arrest when necessary. Triggered by p53 activation p21 contributes to preventing undisturbed cell proliferation acting as a safeguard against tumor formation.

Associated diseases and disorders

P21's deregulation associates with cancer and age-related diseases. Its impairment is a common feature in many cancers often linked with defects in the p53 pathway. Reduced p21 expression can contribute to unchecked cell division and tumor progression. Moreover in age-related diseases p21's role in promoting cellular senescence connects it with degenerative conditions. The intricate relationship between p21 and proteins such as p53 and cyclins highlights its potential as a therapeutic target for these disorders.

Product promise

We are dedicated to supporting your work with high quality reagents and we are here for you every step of the way should you need us.

In the unlikely event of one of our products not working as expected, you are covered by our product promise.

Full details and terms and conditions can be found here:
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10 product images

  • Western blot - Anti-p21 antibody [EPR3993] (ab109199), expandable thumbnail

    Western blot - Anti-p21 antibody [EPR3993] (ab109199)

    False colour image of Western blot: Anti-p21 antibody [EPR3993] staining at 1/1000 dilution, shown in green; Mouse anti-Alpha Tubulin [DM1A] (Anti-alpha Tubulin antibody [DM1A] - Loading Control ab7291) loading control staining at 1/20000 dilution, shown in red. In Western blot, ab109199 was shown to bind specifically to p21. A band was observed at 21 kDa in wild-type HeLa cell lysates with no signal observed at this size in CDKN2A knockout cell line Human CDKN1A knockout HeLa cell line ab255349 (knockout cell lysate ab263812). To generate this image, wild-type and CDKN2A knockout cell lysates were analysed. First, samples were run on an SDS-PAGE gel then transferred onto a nitrocellulose membrane. Membranes were blocked in 3 % milk in TBS-0.1 % Tween® 20 (TBS-T) before incubation with primary antibodies overnight at 4°C. Blots were washed four times in TBS-T, incubated with secondary antibodies for 1 h at room temperature, washed again four times then imaged.Secondary antibodies used were Goat anti-Rabbit IgG H&L (IRDye® 800CW) preabsorbed (Goat anti-Rabbit IgG H&L (IRDye® 800CW) preadsorbed ab216773) and Goat anti-Mouse IgG H&L (IRDye® 680RD) preabsorbed (Goat anti-Mouse IgG H&L (IRDye® 680RD) preadsorbed ab216776) at 1/20000 dilution.

    All lanes: Western blot - Anti-p21 antibody [EPR3993] (ab109199) at 1/1000 dilution

    Lane 1: wild-type HeLa Vehicle Control Fluvastatin (0 uM, 24 h) cell lysate at 20 µg

    Lane 2: wild-type HeLa Treated Fluvastatin (50 uM, 24 h) cell lysate at 20 µg

    Lane 3: CDKN1A knockout HeLa Vehicle Control Fluvastatin (0 uM, 24 h) cell lysate at 20 µg

    Lane 4: CDKN1A knockout HeLa Treated Fluvastatin (50 uM, 24 h) cell lysate at 20 µg

    Performed under reducing conditions.

    Predicted band size: 18 kDa

    Observed band size: 21 kDa

  • Western blot - Anti-p21 antibody [EPR3993] (ab109199), expandable thumbnail

    Western blot - Anti-p21 antibody [EPR3993] (ab109199)

    Lane 1: Wild-type DLD-1 cell lysate (20 μg)

    Lane 2: Wild-type DLD-1 20 μM 2,3-DCPE for 16hrs treated cell lysate (20 μg)

    Lane 3: p21 knockout DLD-1 cell lysate (20 μg)

    Lane 4: p21 knockout 20 μM 2,3-DCPE for 16hrs DLD-1 cell lysate (20 μg)

    Lane 5: HT1080 cell lysate (20 μg)


    Lanes 1 - 5: Merged signal (red and green). Green - ab109199 observed at 20 kDa. Red - loading control, Anti-GAPDH antibody [6C5] - Loading Control ab8245, observed at 37 kDa.

    ab109199 was shown to recognize p21 in WT DLD-1 cells with 2,3-DCPE treatment along with additional cross-reactive bands. When p21 knockout DLD-1 cells +/- 2,3-DCPE treatment were used, no band was observed. Wild-type and p21 knockout samples were subjected to SDS-PAGE. ab109199 and Anti-GAPDH antibody [6C5] - Loading Control ab8245 (loading control to GAPDH) were diluted 1/1000 and 1/10 000 respectively and incubated overnight at 4°C. Blots were developed with Goat anti-Rabbit IgG H&L (IRDye® 800CW) preadsorbed (Goat anti-Rabbit IgG H&L (IRDye® 800CW) preadsorbed ab216773) and Goat anti-Mouse IgG H&L (IRDye® 680RD) preadsorbed (Goat anti-Mouse IgG H&L (IRDye® 680RD) preadsorbed ab216776) secondary antibodies at 1/10 000 dilution for 1 h at room temperature before imaging.

    All lanes: Western blot - Anti-p21 antibody [EPR3993] (ab109199)

    Predicted band size: 18 kDa

    Observed band size: 20 kDa

  • Western blot - Anti-p21 antibody [EPR3993] (ab109199), expandable thumbnail

    Western blot - Anti-p21 antibody [EPR3993] (ab109199)

    Lanes 1- 2: Merged signal (red and green). Green - ab109199 observed at 20 kDa. Red - Anti-GAPDH antibody [6C5] - Loading Control (Anti-GAPDH antibody [6C5] - Loading Control ab8245) observed at 37 kDa.

    ab109199 was shown to react with p21 in wild-type HCT116 cells in western blot. Loss of signal was observed when knockout cell line Human CDKN1A knockout HCT116 cell line ab266860 (knockout cell lysate Human CDKN1A knockout HCT116 cell lysate ab256870) was used. Wild-Type HCT116 and CDKN1A knockout HCT116 cell lysates were subjected to SDS-PAGE. Membrane was blocked for 1 hour at room temperature in 0.1% TBST with 3% non-fat dried milk. ab109199 and Anti-GAPDH antibody [6C5] - Loading Control (Anti-GAPDH antibody [6C5] - Loading Control ab8245) overnight at 4°C at a 1 in 1000 dilution and a 1 in 20000 dilution respectively. Blots were developed with Goat anti-Rabbit IgG H&L (IRDye®800CW) preadsorbed (Goat anti-Rabbit IgG H&L (IRDye® 800CW) preadsorbed ab216773) and Goat anti-Mouse IgG H&L (IRDye®680RD) preadsorbed (Goat anti-Mouse IgG H&L (IRDye® 680RD) preadsorbed ab216776) secondary antibodies at 1 in 20000 dilution for 1 hour at room temperature before imaging.

    All lanes: Western blot - Anti-p21 antibody [EPR3993] (ab109199) at 1/1000 dilution

    Lane 1: Wild-type HCT116 cell lysate at 20 µg

    Lane 2: CDKN1A knockout HCT116 cell lysate at 20 µg

    Performed under reducing conditions.

    Predicted band size: 18 kDa, 197 kDa, 36 kDa, 47 kDa, 72 kDa, 84 kDa

    Observed band size: 150 kDa, 20 kDa, 40 kDa, 45 kDa, 47 kDa

  • Western blot - Anti-p21 antibody [EPR3993] (ab109199), expandable thumbnail

    Western blot - Anti-p21 antibody [EPR3993] (ab109199)

    Different batches of ab109199 were tested on MCF7 (Human breast adenocarcinoma epithelial cell) lysate at 0.2 µg/ml. 15 µg of lysate was loaded in each lane. Bands observed at 21 kDa.

    All lanes: Western blot - Anti-p21 antibody [EPR3993] (ab109199)

    Predicted band size: 18 kDa

  • Western blot - Anti-p21 antibody [EPR3993] (ab109199), expandable thumbnail

    Western blot - Anti-p21 antibody [EPR3993] (ab109199)

    Blocking and diluting buffer: 5% NDFM/TBST.

    All lanes: Western blot - Anti-p21 antibody [EPR3993] (ab109199)

    All lanes: MCF-7 (Human breast adenocarcinoma epithelial cell) whole cell lysates at 15 µg

    Secondary

    All lanes: Western blot - Goat Anti-Rabbit IgG H&L (HRP) (Goat Anti-Rabbit IgG H&L (HRP) ab97051) at 1/20000 dilution

    Predicted band size: 18 kDa

    Exposure time: 3min

  • Western blot - Anti-p21 antibody [EPR3993] (ab109199), expandable thumbnail

    Western blot - Anti-p21 antibody [EPR3993] (ab109199)

    All lanes: Western blot - Anti-p21 antibody [EPR3993] (ab109199)

    Lane 1: RAW264.7 (Mouse Abelson murine leukemia virus-induced tumor macrophage) whole cell lysates at 15 µg

    Lane 2: Neuro-2a (Mouse neuroblastoma neuroblast) whole cell lysates at 15 µg

    Secondary

    All lanes: Western blot - Goat Anti-Rabbit IgG H&L (HRP) (Goat Anti-Rabbit IgG H&L (HRP) ab97051) at 1/20000 dilution

    Predicted band size: 18 kDa

    This data was developed using ab109199, the same antibody clone in a different buffer formulation.

  • Western blot - Anti-p21 antibody [EPR3993] (ab109199), expandable thumbnail

    Western blot - Anti-p21 antibody [EPR3993] (ab109199)

    Lane 1: Wild-type DLD-1 cell lysate (20 μg)
    Lane 2: Wild-type DLD-1 20 μM 2,3-DCPE for 16hrs treated cell lysate (20 μg)
    Lane 3: p21 knockout DLD-1 cell lysate (20 μg)
    Lane 4: p21 knockout 20 μM 2,3-DCPE for 16hrs DLD-1 cell lysate (20 μg)
    Lane 5: HT1080 cell lysate (20 μg)

    Lanes 1 - 5: Merged signal (red and green). Green - ab109199 observed at 20 kDa. Red - loading control, Anti-GAPDH antibody [6C5] - Loading Control ab8245, observed at 37 kDa.

    This western blot image is a comparison between Anti-PIST antibody [EPR4079] ab109119 and a competitor's top cited rabbit polyclonal antibody.

    All lanes: Western blot - Anti-p21 antibody [EPR3993] (ab109199)

    Predicted band size: 18 kDa

  • Western blot - Anti-p21 antibody [EPR3993] (ab109199), expandable thumbnail

    Western blot - Anti-p21 antibody [EPR3993] (ab109199)

    Blocking buffer and concentration: 5% NFDM/TBST.

    Diluting buffer and concentration: 5% NFDM /TBST.

    All lanes: Western blot - Anti-p21 antibody [EPR3993] (ab109199) at 1/1000 dilution

    All lanes: PC-12 cell lysate at 10 µg

    Secondary

    All lanes: Peroxidase-conjugated goat anti-rabbit IgG (H+L) at 1/1000 dilution

    Predicted band size: 18 kDa

    Observed band size: 21 kDa

  • Western blot - Anti-p21 antibody [EPR3993] (ab109199), expandable thumbnail

    Western blot - Anti-p21 antibody [EPR3993] (ab109199)

    Blocking and diluting buffer and concentration: 5% NFDM/TBST.

    Anti-GAPDH antibody [EPR16891] - Loading Control ab181602 was used as a GAPDH loading control.

    We recommend using higher or super higher sensitivity ECL substrate for detecting.

    Increase lysate amount can also help to get stronger signal.

    All lanes: Western blot - Anti-p21 antibody [EPR3993] (ab109199) at 1/1000 dilution

    Lane 1: PC-12(Rat adrenal gland pheochromocytoma) whole cell lysate at 20 µg

    Lane 2: PC-12(Rat adrenal gland pheochromocytoma) treated with 50ng/ml NFG for 48 hours whole cell lysate at 20 µg

    Secondary

    All lanes: Western blot - Goat Anti-Rabbit IgG H&L (HRP) (Goat Anti-Rabbit IgG H&L (HRP) ab97051) at 1/20000 dilution

    Developed using the ECL technique.

    Predicted band size: 18 kDa

    Observed band size: 18 kDa

    Exposure time: 180s

  • Western blot - Anti-p21 antibody [EPR3993] (ab109199), expandable thumbnail

    Western blot - Anti-p21 antibody [EPR3993] (ab109199)

    Blocking and diluting buffer and concentration: 5% NFDM/TBST.

    Anti-GAPDH antibody [EPR16891] - Loading Control ab181602 was used as a GAPDH loading control.

    All lanes: Western blot - Anti-p21 antibody [EPR3993] (ab109199) at 1/1000 dilution

    Lane 1: Raw 264.7(Mouse Abelson murine leukemia virus-induced tumor macrophage) whole cell lysate at 20 µg

    Lane 2: NIH/3T3 (Mouse embryonic fibroblast) whole cell lysate at 20 µg

    Lane 3: C6 (Rat glial tumor glial cell) whole cell lysate at 20 µg

    Lane 4: PC-12(Rat adrenal gland pheochromocytoma) whole cell lysate at 20 µg

    Secondary

    All lanes: Western blot - Goat Anti-Rabbit IgG H&L (HRP) (Goat Anti-Rabbit IgG H&L (HRP) ab97051) at 1/20000 dilution

    Predicted band size: 18 kDa

    Observed band size: 18 kDa

    Exposure time: 180s

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