Fig. 4.

133p53 promotes DNA repair. (A) RAD51 protein in sham and irradiated astrocytes expressing either control vector (pLOC) or Δ133p53. (B) Quantification and (C) representative western blots of RAD51 protein in irradiated astrocytes expressing pLOC or Δ133p53 at low and high confluency. (D) Labeling of DNA double-strand breaks with γH2AX in transduced, irradiated astrocytes. (E) Quantitative summary of γH2AX staining on day 6 in irradiated human astrocytes transduced with pLOC or Δ133p53 on day 3 after radiation exposure (2 Gy). (F) Representative image of RAD51 and γH2AX labeling 4 hours after radiation exposure. (G) Quantification of γH2AX- and (H) 53BP1-positive foci at 4 and 24 hours after radiation exposure in astrocytes transduced prior to radiation treatment. NS indicates P > 0.05, *P ≤ 0.05, **P ≤ 0.01, and ***P ≤ 0.001 by unpaired 2-tailed Student’s t-test. Scale = 5 μm.