Fig. 8: H2B mediates ATF3 function in SC activation and muscle regeneration.

a Upper: Schematic for overexpressing H2B in vitro. FISCs from Ctrl or iKO mice were transfected with a control (Ctrl) or pCDNA-H2B plasmid and EdU assay was performed for assessing SC activation. Lower: Schematic for overexpressing H2B in vivo via lenti virus. H2B expressing lentivirus was injected into Ctrl or iKO TA muscles 1 day after BaCl₂ injury and the muscles were collected 5 days after infection for analysis. b Left: The above transfected cells were cultured for 24 h before treated with EdU for 6 h; EdU positive cells were stained and quantified. Scale bar: 50 μm; n = 3 mice per group. p = 0.44 and 0.0013. c H&E staining of the above TA muscles collected at 5 dpi after infection. Scale bar: 50 μm. n = 4 mice per group. d IF staining of eMyHC (red) and Laminin (green) was performed on the above TA muscles. Scale bar: 50 μm. e The numbers of eMyHC+ fibers per view were quantified. n = 4 mice per group. From left to right, p = 0.20, 0.00081, 0.052 and 0.012. f Left: IF staining of Pax7 (red) and Laminin (green) was performed on the above TA muscles. Scale bar: 50 μm. Right: the numbers of Pax7+ cells per view were quantified. n = 4 mice per group. From left to right, p = 0.33, 0.041, 0.67 and 0.0052. g Left: IF staining of Myod (red) and Laminin (green) was performed on the above TA muscles. Scale bar: 50 μm. Right: the numbers of Myod+ cells per view were quantified. n = 4 mice per group. From left to right, p = 0.0053, 0.0058, 0.12 and 0.020. All the bar graphs are presented as mean ± SD. Student’s t test (two-tailed unpaired) was used to calculate the statistical significance (b, e–g): *p < 0.05, **p < 0.01, ***p < 0.001. n.s. no significance. Source data are provided as a Source Data file.