Inhibition of RAD54 and DNA-PKcs expression in cell lines constitutively expressing shRNA. Indirect immunofluorescence analysis of RAD54 and DNA-PKcs expression in cell lines constitutively expressing shRNA. (a) Distribution of the number of RAD54 foci detected in 50 cells of the HeLa parental cell line and in four clones knocked down for RAD54 (clones 3.3a, 3.4d, 3.1b and 3.1c). The number of foci per cell (X-axis) and the number of cells (Y-axis) are reported. Solid lines in red represent Normal distributions. The mean number of foci per cell is indicated for each cell line. (b) Examples of immunofluorescence using antibodies against the human RAD54 (left section of the panel) and the human DNA-PKcs (right section of the panel) proteins on the clones shRAD54 3.3a and shRAD54/CRPK 2b. In both cases the HeLa parental cell line was used as positive control. (c) Western blot analysis of DNA-PKcs and RAD54 expression in single and double knocked down clones. Tubulin was used as loading control.