Fig. 4

H2AS40Gc is involved in the DNA damage repair mechanism. a Left, WB analysis in mESC lines stably expressing 3 × FLAG-fused H2A3-WT (WT) or S40A mutant. Lamin B was used as the internal control. Right, bar graph was visualized from the band intensities of endogenous (black arrowhead) and exogenous (white arrowhead) H2AS40Gc calculated by the ImageJ software. Values were normalized by the intensities of Lamin B and expressed as relative to expression of endogenous H2AS40Gc in mESCs expressing Flag-only. b Electrophoresis image of genomic DNA of H2A3-WT mESCs (WT) and S40A mESCs (S40A-mutant) treated with ETP. c Ratio of the fragmented genomic DNA in H2A3-WT and S40A-mutant mESCs treated with ETP. Bar graph was visualized from intensities of electrophoresis image calculated by the ImageJ software. Values of fragmented genomic DNA were normalized to the intensity of total genomic DNA and expressed as the relative ratio in biological triplicate experiments. **p < 0.01 (Student’s t-test). d Time-course experiments of the viability of mESCs in the presence of ETP and bleomycin (BLM). mESCs stably expressing H2A3-WT and S40A-mutant were used, and cell viabilities were measured by the WST-1 assay. Values were normalized to 0 h and indicated as mean ± S.D. (n = 3). **p < 0.01, *p < 0.05 (Student’s t-test, WT #1 & #2 versus S40A #1 & #2)