Fig. 6: EDB(+) FN interacts with integrins and regulates the cell cycle.

a Principal component analysis (PCA) of the global proteomic signature of siEDB(+) FN and siEDB(−) FN and siSCR treated MuSC-derived myoblasts as determined by mass spectrometry. b Venn diagram showing the overlap of significantly regulated proteins with log2 fold change (log2FC) > 0.58 and adjusted p-value  <  0.1 in siEDB(+) FN or siEDB(−) FN treated MuSC-derived myoblasts when compared to the siSCR condition. c Visualization of KEGG pathways enriched with an adjusted p-value < 0.05 based on differntially regulated proteins in MuSC-derived myoblasts after siEDB(+) FN treatment compared to the siSCR condition. d Violin plots showing the log2FC of individual proteins in selected KEGG pathways differentially affected in MuSC-derived myoblasts treated with siEDB(+) FN compared to the siSCR condition. e Heatmap showing log2FC of all quantified proteins in the “Cell cycle” and “ECM-Receptor interaction” KEGG pathways in MuSC-derived myoblasts treated with siEDB(+) FN compared to the siSCR condition. Integrin subunits are highlighted in green fonts. f, g Representative immunostaining and quantification of activated integrin β1 (act-Itgβ1, green) fluorescence intensity in MuSC-derived myoblasts after treatement with siEDB(+) FN or siSCR. DNA (blue) was counterstained using DAPI. Scale bar = 10 µm. h–j Representative immunostaining and quantification of total cell numbers and Pax7+ (green) MuSC-derived integrin β1 knockout (Itgβ1-/-) myoblasts after treatement with siEDB(+) FN or siSCR. DNA (blue) was counterstained using DAPI. Scale bar = 200 µm. siRNAs termed siEDB(+) FN and siEDB(−) FN (a–j) correspond to the siRNAs with the suffix _a described in Fig. 2c. Data points represent n = 3 biological replicates per condition, each from an independent myoblast line isolated from separate young mice (a), and bars show means from n = 3 biological replicates per condition, each from an independent myoblast line isolated from separate young mice (g, i, j). KEGG enrichment p-values (c) were calculated using Fisher’s exact test. Error bars represent SEM and p-values (g, i, j) were calculated using a one-tailed Student’s t-test. **p < 0.01. Source data are provided as a Source Data file.