Fig. 1: ATF3 is rapidly and transiently induced during SC early activation.

a Schematic for isolation of quiescent satellite cells (QSC) after in situ fixation, freshly isolated SCs (FISC) without prior fixation from muscles of Tg: Pax7-nGFP mice. FISCs were subsequently cultured and activated for 24 (ASC-24h), 48 (ASC-48h), or 72 h (DSC-72h). RNAs were extracted for RNA-Seq analysis. Created with BioRender.com. b Heat maps indicating gene expression levels (Log2[FPKM]) of AP-1 family TFs detected by the RNA-Seq. c, d Expression levels (FPKM) and genomic snapshots of Atf3, Atf4, Fos, FosB, JunB mRNAs from the above RNA-Seq. e RT-qPCR detection of Atf3 in the above cells. n = 3 mice per group. p = 0.000025, 0.12, 0.0000011 and 0.0000052. f Immunofluorescence (IF) staining of ATF3 and Pax7 proteins on the above cells. Scale bar: 50 μm. g IF staining of ATF3 and Pax7 proteins on single myofibers from EDL muscles immediately after isolation or cultured for 24 h. Scale bar: 25 μm. h IF staining of ATF3 and Pax7 protein on TA muscle sections from uninjured mice or 1, 2 and 3 dpi. Scale bar: 50 μm. All the bar graphs are presented as mean ± SD. Student’s t test (two-tailed unpaired) was used to calculate the statistical significance (e): *p < 0.05, **p < 0.01, ***p < 0.001. n.s. no significance. Source data are provided as a Source Data file.