Figure 6.

Depletion of cyclin D1 impairs radiation-induced formation of RAD51 foci. (A) Representative images of radiation-induced RAD51 foci in MDA-MB-231 cells. The MDA-MB-231 cells were transfected with either control siRNA or CCND1 siRNA, followed by irradiation with 4 Gy of X-rays or protons. The cells were fixed at the indicated times and stained with DAPI (blue) and RAD51 (green), as described in the materials and methods. (B) Kinetics of cells with RAD51 foci (n ≥ 5) after 4 Gy of X-rays or protons. Data are presented as the mean ± SEM of two independent experiments (n = 40). (C) Depletion of cyclin D1 decreased RAD51 expression. β-Actin was used as a loading control.