Figure 2.

53BP1-Dependent p53 Regulation Requires Oligomerization and BRCT Domain-Mediated p53 Interactions

(A) Schematic representation of the 53BP1 domain and point mutants examined for restoration of N3 sensitivity.

(B) Western blot showing comparable expression of 53BP1 mutants upon stable lentivirus-mediated transduction in 53BP1Δ MCF-7.

(C) Indicated cell lines treated with N3 (4 μM) for 11 days or left untreated for 7 days were fixed and stained with crystal violet. Relative N3 resistance normalized to control (GFP)-complemented 53BP1Δ. Mean of three biological replicates ± SD.

(D) Flag-HA-53BP1 proteins purified from cell lysates of indicated stably complemented 53BP1Δ MCF-7 lines following N3 treatment. Interacting proteins analyzed by immunoblotting.

(E) Similar to (D), but the composition of p53 immunoprecipitates was analyzed. See also Figure S3.