• Product name

  • Description

    Rabbit polyclonal to CtIP
  • Host species

  • Tested applications

    Suitable for: WB, IPmore details
  • Species reactivity

    Reacts with: Mouse, Human
    Predicted to work with: Pig, Chimpanzee, Baboon, Rhesus monkey, Orangutan
  • Immunogen

    Synthetic peptide within Human CtIP aa 850-897 (C terminal). The exact sequence is proprietary. (NP_002885.1).
    Database link: Q99708

  • Positive control

    • MCF7 and HeLa whole cell lysate (ab150035).



Our Abpromise guarantee covers the use of ab70163 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
WB 1/1000 - 1/5000. Detects a band of approximately 150 kDa (predicted molecular weight: 102 kDa).
IP Use at 2 µg/mg of lysate.


  • Function

    Endonuclease that cooperates with the MRE11-RAD50-NBN (MRN) complex in processing meiotic and mitotic double-strand breaks (DSBs) by ensuring both resection and intrachromosomal association of the broken ends. Functions downstream of the MRN complex and ATM, promotes ATR activation and its recruitment to DSBs in the S/G2 phase facilitating the generation of ssDNA. Component of the BRCA1-RBBP8 complex that regulates CHEK1 activation and controls cell cycle G2/M checkpoints on DNA damage. Promotes microhomology-mediated alternative end joining (A-NHEJ) during class-switch recombination and plays an essential role in chromosomal translocations.
  • Involvement in disease

    Seckel syndrome 2
    Jawad syndrome
    Genetic variability in RBBP8 is noted as a factor in BRCA1-associated breast cancer risk (PubMed:21799032). Exhibits sensitivity to tamoxifen in certain breast cancer cell lines (PubMed:18171986).
  • Sequence similarities

    Belongs to the COM1/SAE2/CtIP family.
  • Domain

    The PXDLS motif binds to a cleft in CtBP proteins.
    The damage-recruitment motif is required for DNA binding and translocation to sites of DNA damage.
  • Post-translational

    Acetylated. Deacetylation by SIRT6 upon DNA damage promotes DNA end resection.
    Hyperphosphorylation upon ionizing radiation results in dissociation from BRCA1. Phosphorylation at Thr-847 by CDK1 is essential for the recruitment to DNA and the DNA repair function. Phosphorylated on Ser-327 as cells enter G2 phase. This phosphorylation is required for binding BRCA1 and for the G2/M DNA damage transition checkpoint control.
    Ubiquitinated (PubMed:14654780, PubMed:16818604). Ubiquitination at multiple sites by BRCA1 (via its N-terminal RING domain) does not lead to its proteosomal degradation but instead the ubiquitinated RBBP8 binds to chromatin following DNA damage and may play a role in G2/M checkpoint control (PubMed:16818604). Ubiquitinated by RNF138 at its N-terminus (PubMed:26502057).
  • Cellular localization

    Nucleus. Chromosome. Associates with sites of DNA damage in S/G2 phase (PubMed:10764811). Ubiquitinated RBBP8 binds to chromatin following DNA damage (PubMed:16818604).
  • Information by UniProt
  • Database links

  • Alternative names

    • COM1 antibody
    • COM1_HUMAN antibody
    • CtBP interacting protein antibody
    • CtBP-interacting protein antibody
    • CtIP antibody
    • DNA endonuclease RBBP8 antibody
    • JWDS antibody
    • RB binding protein 8 endonuclease antibody
    • RBBP-8 antibody
    • RBBP8 antibody
    • Retinoblastoma-binding protein 8 antibody
    • Retinoblastoma-interacting protein and myosin-like antibody
    • Rim antibody
    • SAE2 antibody
    • SCKL2 antibody
    • Sporulation in the absence of SPO11 protein 2 homolog antibody
    see all


  • All lanes : Anti-CtIP antibody (ab70163) at 1 µg/ml

    Lane 1 : MCF7 whole cell lysate at 50 µg
    Lane 2 : MCF7 whole cell lysate at 15 µg
    Lane 3 : MCF7 whole cell lysate at 5 µg
    Lane 4 : HeLa whole cell lysate at 50 µg

    Predicted band size: 102 kDa
    Observed band size: 150 kDa
    why is the actual band size different from the predicted?

  • CtIP was immunoprecipitated from 293T cells using NETN lysis buffer with ab70163 at 2ug/mg of lysate. 

    Chemiluminescence with an exposure time: 3 minutes


This product has been referenced in:

  • Saquilabon Cruz GM  et al. Femtosecond near-infrared laser microirradiation reveals a crucial role for PARP signaling on factor assemblies at DNA damage sites. Nucleic Acids Res 44:e27 (2016). ICC/IF . Read more (PubMed: 26424850) »
  • Xu G  et al. REV7 counteracts DNA double-strand break resection and affects PARP inhibition. Nature 521:541-544 (2015). WB ; Human . Read more (PubMed: 25799992) »
See all 8 Publications for this product

Customer reviews and Q&As

1-2 of 2 Abreviews or Q&A

Western blot
Human Cell lysate - whole cell (Hela)
Gel Running Conditions
Reduced Denaturing
Loading amount
10 µg
Blocking step
Milk as blocking agent for 30 minute(s) · Concentration: 5% · Temperature: 25°C

Abcam user community

Verified customer

Submitted Jul 01 2016

Western blot
Saccharomyces cerevisiae Cell lysate - whole cell (exponentially growing yeast cells)
Loading amount
1e+007 cells
exponentially growing yeast cells
Gel Running Conditions
Reduced Denaturing (gel 10% SDS page)
Blocking step
Milk as blocking agent for 1 hour(s) and 0 minute(s) · Concentration: 5% · Temperature: RT°C

Dr. Ilaria Guerini

Verified customer

Submitted Aug 21 2012

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