Figure 5

Pentamidine might affect DNA damage response through acetylation of histone H2A. (A) The effect of pentamidine on histone acetylation. MRC5SV cells were irradiated with 5 Gy of γ-ray with or without pre-treatment of pentamidine (0.5 mM, 30 minutes). These cells were harvested at indicated times after IR and analyzed by Western blot using indicated antibodies. (B) Acetylation of histone H2A is required for IR-induced foci formation. H2A-WT or H2A-K5/9R-expressing cells were generated as described in Materials and Methods. These cells were irradiated with 5 Gy of γ-ray. After 30 minutes, their cells were fixed and immuno-staining was performed using anti-NBS1 and anti-FLAG antibodies. Percentage of NBS1 foci-positive cells was shown in (C). (D) HR activity in H2A (K5/9R)-expressing cells. I-SceI expression plasmids were introduced into H2A-WT or H2A-K5/9R- expressing cells by electroporation. After 2 days GFP-positive cells, induced through HR pathway, were analyzed by flowcytometer.