Fig 2. Modulation of histone PTMs by ssUVR.

HaCaT cells were exposed to a single dose of ssUV (1xUV) at 12 J/cm² or 3 repetitive radiations of the same dose (3xUV). Cells were harvested at 24 hr after the last exposure, and the levels of H3K4me3, H3K9me2, H3K27me3, pan H3ac, pan H4ac, H3K9ac, and H4K16ac were analyzed by western blot analysis using specific antibodies. An antibody against histone H3 was used to assess the loading of samples in each lane. (A) Representative western blot. (B) The relative intensity of the bands was presented as the ratio of each band versus its corresponding H3. The results from replicate experiments were plotted as the mean ± SD (n = 3). Statistical significance of the difference between sham and ssUVR-treated cells was analyzed using Student's t-test. * P < 0.05.