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53Bp1-/- (ATCC® CRL-3257)

Organism: Mus musculus, mouse  /  Cell Type: fibroblast  /  Tissue: embryo  / 

Permits and Restrictions

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Organism Mus musculus, mouse
Tissue embryo
Cell Type fibroblast
Product Format frozen 1.0 mL
Culture Properties adherent
Biosafety Level 1

Biosafety classification is based on U.S. Public Health Service Guidelines, it is the responsibility of the customer to ensure that their facilities comply with biosafety regulations for their own country.

Age 12.5 days
Applications Experiments using this cell line, ATCC CRL-3263, and ATCC CRL-3264 show that 53Bp1 and Brac1 regulate the choice between NHEJ and HR pathways, which has implications for anticancer therapies using PARP inhibitors. CRL-3264 with the removed 53Bp1-/1 mutant restores HR pathways in DNA double strand break repair. These cell lines can be use for cancer research and drug development applications.
Storage Conditions liquid nitrogen vapor phase
Images Cell Micrograph of 53Bp1-/- ATCC CRL-3257 cells
Comments 53Bp1 inhibits homologous recombination in Brac1-Deficient cells by blocking resection of DNA breaks
Complete Growth Medium

The base medium for this cell line is DMEM: F12 (ATCC 30-2002). To make the complete medium add the following components to 500 mL of the base medium:

  • 56 mL fetal bovine serum (FBS; ATCC 30-2020)

Note: Be sure to heat inactivate the serum at 56°C for 30 minutes

Volumes used in this protocol are for 75 cm2 flask; proportionally reduce or increase amount of dissociation medium for culture vessels of other sizes. Corning® T-75 flasks (catalog #430641) are recommended for subculturing this product.
  1. Remove and discard culture medium.
  2. Briefly rinse the cell layer with DPBS (ATCC catalog # 30-2200) to remove all traces of serum that contains trypsin inhibitor.
  3. Add 2.0 to 3.0 mL 0.25% (w/v) Trypsin- 0.53 mM EDTA solution to flask and observe cells under an inverted microscope until cell layer is dispersed (usually within 5 to 15 minutes).
    Note: To avoid clumping do not agitate the cells by hitting or shaking the flask while waiting for the cells to detach. Cells that are difficult to detach may be placed at 37°C to facilitate dispersal.
  4. Add 6.0 to 8.0 mL of complete growth medium and aspirate cells by gently pipetting.
  5. Add appropriate aliquots of the cell suspension to new culture vessels.
    Cultures can be established between 2x 104 and 4 x 104 viable cells/cm2.
  6. Incubate cultures at 37°C.
Interval: Maintain cultures at a cell concentration between 2 X 104 and 2.0 X 105 cell/cm2.
Subcultivation Ratio: A subcultivation ratio of 1:3 to 1:8 is recommended
Medium Renewal: 2 to 3 times per week
Culture Conditions
Atmosphere: air, 95%; carbon dioxide (CO2), 5%
Temperature: 37°C
Cells per Vial approximately 1.5 to 2.5 x 106
Volume 1.0 mL
Sterility Tests Bacteria and yeast: No growth
Mycoplasma: No growth
Viability ≥ 50%
Name of Depositor A Nussenzweig, LGI/NCI, Bethesda, MD
Year of Origin estimated to be 2002

Bunting SF, et al. 53BP1 inhibits homologous recombination in Brca1-deficient cells by blocking resection of DNA breaks. Cell 141(2): 243-254, 2010. PubMed: 20362325

Notice: Necessary PermitsPermits

These permits may be required for shipping this product:

  • Customers located in the state of Hawaii will need to contact the Hawaii Department of Agriculture to determine if an Import Permit is required. A copy of the permit or documentation that a permit is not required must be sent to ATCC in advance of shipment.
Basic Documentation
Other Documentation

Bunting SF, et al. 53BP1 inhibits homologous recombination in Brca1-deficient cells by blocking resection of DNA breaks. Cell 141(2): 243-254, 2010. PubMed: 20362325