• Product name

    Anti-KAP1 antibody [20C1] - ChIP Grade
    See all KAP1 primary antibodies
  • Description

    Mouse monoclonal [20C1] to KAP1 - ChIP Grade
  • Host species

  • Tested applications

    Suitable for: ChIP, IHC-P, ICC/IF, WB, EMSA, IPmore details
  • Species reactivity

    Reacts with: Mouse, Rat, Human
  • Immunogen

    Recombinant fragment, corresponding to amino acids 60-383 of Human KAP1.

  • Positive control



Our Abpromise guarantee covers the use of ab22553 in the following tested applications.

The application notes include recommended starting dilutions; optimal dilutions/concentrations should be determined by the end user.

Application Abreviews Notes
ChIP Use at an assay dependent dilution.
IHC-P Use a concentration of 5 µg/ml.
ICC/IF Use a concentration of 2 - 4 µg/ml.
WB Use a concentration of 1 µg/ml. Detects a band of approximately 100 kDa (predicted molecular weight: 88.5 kDa).
EMSA Use at an assay dependent dilution.
IP Use at an assay dependent concentration.


  • Function

    Nuclear corepressor for KRAB domain-containing zinc finger proteins (KRAB-ZFPs). Mediates gene silencing by recruiting CHD3, a subunit of the nucleosome remodeling and deacetylation (NuRD) complex, and SETDB1 (which specifically methylates histone H3 at 'Lys-9' (H3K9me)) to the promoter regions of KRAB target genes. Enhances transcriptional repression by coordinating the increase in H3K9me, the decrease in histone H3 'Lys-9 and 'Lys-14' acetylation (H3K9ac and H3K14ac, respectively) and the disposition of HP1 proteins to silence gene expression. Recruitment of SETDB1 induces heterochromatinization. May play a role as a coactivator for CEBPB and NR3C1 in the transcriptional activation of ORM1. Also corepressor for ERBB4. Inhibits E2F1 activity by stimulating E2F1-HDAC1 complex formation and inhibiting E2F1 acetylation. May serve as a partial backup to prevent E2F1-mediated apoptosis in the absence of RB1. Important regulator of CDKN1A/p21(CIP1). Has E3 SUMO-protein ligase activity toward itself via its PHD-type zinc finger.
  • Tissue specificity

    Expressed in all tissues tested including spleen, thymus, prostate, testis, ovary, small intestine, colon and peripheral blood leukocytes.
  • Pathway

    Protein modification; protein sumoylation.
  • Sequence similarities

    Belongs to the TRIM/RBCC family.
    Contains 2 B box-type zinc fingers.
    Contains 1 bromo domain.
    Contains 1 PHD-type zinc finger.
    Contains 1 RING-type zinc finger.
  • Domain

    The HP1 box is both necessary and sufficient for HP1 binding.
    The PHD-type zinc finger enhances CEBPB transcriptional activity. The PHD-type zinc finger, the HP1 box and the bromo domain, function together to assemble the machinery required for repression of KRAB domain-containing proteins. Acts as an intramolecular SUMO E3 ligase for autosumoylation of bromodomain.
    The RING-finger-B Box-coiled-coil/tripartite motif (RBCC/TRIM motif) is required for interaction with the KRAB domain of KRAB-zinc finger proteins. Binds four zinc ions per molecule. The RING finger and the N-terminal of the leucine zipper alpha helical coiled-coil region of RBCC are required for oligomerization.
    Contains one Pro-Xaa-Val-Xaa-Leu (PxVxL) motif, which is required for interaction with chromoshadow domains. This motif requires additional residues -7, -6, +4 and +5 of the central Val which contact the chromoshadow domain.
  • Post-translational

    Phosphorylated upon DNA damage, probably by ATM or ATR. ATM-induced phosphorylation on Ser-824 represses sumoylation leading to the de-repression of expression of a subset of genes involved in cell cycle control and apoptosis in response to genotoxic stress. Dephosphorylation by the phosphatases, PPP1CA and PP1CB forms, allows sumoylation and expression of TRIM28 target genes.
    Sumoylation/desumoylation events regulate TRIM28-mediated transcriptional repression. Sumoylation is required for interaction with CHD3 and SETDB1 and the corepressor activity. Represses and is repressed by Ser-824 phosphorylation. Enhances the TRIM28 corepressor activity, inhibiting transcriptional activity of a number of genes including GADD45A and CDKN1A/p21. Lys-554, Lys-779 and Lys-804 are the major sites of sumoylation. In response to Dox-induced DNA damage, enhanced phosphorylation on Ser-824 prevents sumoylation and allows de-repression of CDKN1A/p21.
  • Cellular localization

    Nucleus. Associated with centromeric heterochromatin during cell differentiation through CBX1.
  • Information by UniProt
  • Database links

  • Alternative names

    • E3 SUMO protein ligase TRIM28 antibody
    • E3 SUMO-protein ligase TRIM28 antibody
    • FLJ29029 antibody
    • KAP 1 antibody
    • KAP-1 antibody
    • KRAB associated protein 1 antibody
    • KRAB interacting protein 1 antibody
    • KRAB-associated protein 1 antibody
    • KRAB-interacting protein 1 antibody
    • KRIP 1 antibody
    • KRIP-1 antibody
    • KRIP1 antibody
    • Nuclear corepressor KAP 1 antibody
    • Nuclear corepressor KAP-1 antibody
    • RING finger protein 96 antibody
    • RNF96 antibody
    • TF1B antibody
    • TIF1 beta antibody
    • TIF1-beta antibody
    • TIF1B antibody
    • TIF1B_HUMAN antibody
    • Transcription intermediary factor 1 beta antibody
    • Transcription intermediary factor 1-beta antibody
    • Trim28 antibody
    • Tripartite motif containing 28 antibody
    • tripartite motif containing protein 28 antibody
    • Tripartite motif-containing protein 28 antibody
    see all


  • Anti-KAP1 antibody [20C1] - ChIP Grade (ab22553) at 1/500 dilution + HeLa whole cell lysate

    Goat anti-mouse-HRP at 1/5000 dilution

    Developed using the ECL technique.

    Performed under reducing conditions.

    Predicted band size: 88.5 kDa

    Exposure time: 1 second

    See Abreview

  • Immunofluorescence analysis of A549 cells, staining KAP1 (green) with ab22553.
    Cells were fixed in 4% paraformaldehyde followed by permeabilization in 0.1% Triton X-100/PBS. Cells were incubated in primary antibody and a FITC-conjugated goat anti-mouse secondary antibody was used to detect staining. Nuclei were stained with DAPI (blue).

  • IHC image of KAP1 staining in Human normal spleen formalin fixed paraffin embedded tissue section, performed on a Leica BondTM system using the standard protocol F. The section was pre-treated using heat mediated antigen retrieval with sodium citrate buffer (pH6, epitope retrieval solution 1) for 20 mins. The section was then incubated with ab22553, 5µg/ml, for 15 mins at room temperature and detected using an HRP conjugated compact polymer system. DAB was used as the chromogen. The section was then counterstained with haematoxylin and mounted with DPX.

    For other IHC staining systems (automated and non-automated) customers should optimize variable parameters such as antigen retrieval conditions, primary antibody concentration and antibody incubation times.


This product has been referenced in:

  • Zhou Y  et al. miR-140-3p inhibits breast cancer proliferation and migration by directly regulating the expression of tripartite motif 28. Oncol Lett 17:3835-3841 (2019). Read more (PubMed: 30881504) »
  • Chen W  et al. ZFP30 promotes adipogenesis through the KAP1-mediated activation of a retrotransposon-derived Pparg2 enhancer. Nat Commun 10:1809 (2019). Read more (PubMed: 31000713) »
See all 44 Publications for this product

Customer reviews and Q&As

1-10 of 20 Abreviews or Q&A

Human Cell lysate - nuclear (Breast cancer cell line T47D)
Negative control
Breast cancer cell line T47D
Detection step
Real-time PCR
Cross-linking (X-ChIP)
Duration of cross-linking step: 10 minute(s) and 0 second(s)
Specification of the cross-linking agent: Formaldehid
Positive control
H1.2 antibody ab4086

Dr. Albert Jordan

Verified customer

Submitted Apr 06 2019

Western blot
Mouse Cell lysate - whole cell (MEF cells)
Gel Running Conditions
Reduced Denaturing (4-12% Gradient Gel)
Loading amount
20 µg
MEF cells
Blocking step
Licor Blocking Buffer as blocking agent for 30 minute(s) · Concentration: 100% · Temperature: 25°C

Abcam user community

Verified customer

Submitted Dec 11 2017

Human Cell lysate - whole cell (U2OS cells)
Total protein in input
500 µg
Immuno-precipitation step
Protein A/G
U2OS cells

Abcam user community

Verified customer

Submitted Jul 18 2017

Western blot
Human Cell lysate - whole cell (Liver)
Gel Running Conditions
Reduced Denaturing (10%)
Loading amount
50 µg
Blocking step
Milk as blocking agent for 2 hour(s) and 0 minute(s) · Concentration: 5% · Temperature: 25°C

Abcam user community

Verified customer

Submitted Dec 27 2016

Western blot
Human Cell lysate - whole cell (B Cells)
Gel Running Conditions
Reduced Denaturing (10% SDS-PAGE)
Loading amount
50 µg
B Cells
Blocking step
Milk as blocking agent for 1 hour(s) and 0 minute(s) · Concentration: 5% · Temperature: 25°C

Abcam user community

Verified customer

Submitted Oct 26 2016


Unfortunately, the epitope for this ab22553Anti-KAP1[20C1] monoclonal antibody has not been specifically mapped.       

The immunogen used is a recombinant fragment, corresponding to amino acids 60-383 of Human KAP1. This was from isoform 1 of the protein (see http://www.uniprot.org/uniprot/Q13263).

Read More


Thank you for contacting us. No, these antibodies have not been tested with overexpression or knockdown cells.

I hope this information is helpful to you. Please do not hesitate to contact us if you need any more advice or information.

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Thank you for confirmation of that.
I have now arranged for the ab10483 to be sent to you. This is on the order number xxxxx (Purchase order number "xxxxx").
I would like to suggest to the customer that with this new antibody, optimisation of the conditions used to perform the Western blotting may be required. Using 5% milk in the diluent buffers may be too high so I would suggest reducing to 1% initially to see what the results yield. If your customer would like help in this optimisation please do not hesitate to ask.
I look forward to hearing how they get on with this antibody.

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Thank you for taking time to complete our questionnaire and providing us with the details of the problems you have encountered with the ab22553.
The details provided will enable us to investigate this case and will provide us with vital information for monitoring product quality. I appreciate the time you have spent in the laboratory and understand your concerns. It is regrettable the results have not been successful.
As the customer has mentioned, I am able to provide the anti-KAP1 antibody ab10484 or ab10483 for the customer to try. Please do let me know which would be preferable and I will arrange this.
Alternatively, I can arrange for a credit note to be issued. Thank you for your cooperation. I look forward to hearing from you with details of how you would like to proceed.

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Thank you for getting back to us with this information.
I am sorry to hear that the customer is still not happy with the results obtained with ab22553. Having looked at the information provided by the customer it seems that the new lot has reduced the level of non-specific band observed at 40 kDa.
In order to investigate this case further, would you be able to ask the customer for a few further details? Could they please fill in the form I have attached to this email, detailing the protocol used with the antibody.
Could they also share an image of the blot of when the antibody worked at a dilution of 1/1000 with only 6 ug of protein? Which type of samples were used?
I will contact the lab to see if they have observed any differences in the intensity of the signal of the antibody.
I look forward to receiving your reply.

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1-10 of 20 Abreviews or Q&A

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