Fig. 4.

DSB repair depends on microtubule networks. a Representative maximum intensity projections of whole z–stacks visualizing 53BP1 foci in ATMwt or ATM^−/− fibroblasts and microtubules using immunofluorescence staining. Untreated, irradiated or colchicine–pretreated fibroblasts (acceptor) were either plated for mono– or co–culture together with MiaPaCa–2 cells (donor; white triangles). b Residual, 24–h 53BP1 foci analyses from 6–Gy x–rays irradiated fibroblasts (acceptor) with or without untreated or colchicine–pretreated MiaPaCa–2 cells (donor). c Residual, 24–h 53BP1 foci analyses from 6–Gy x–rays irradiated fibroblasts (acceptor) in mono–culture, co–culture or transwell (0.4 μm pore size) with MiaPaCa–2 cells (donor). Data represent mean ± SD (n = 20–70 irradiated acceptor cells)