Fig. 4: Ub-proteasomal-related proteome signature in exosomes from β-cat^Δex3 cardiomyocytes.

a Increased Ub-protein abundance in β-cat^Δex3 hearts versus control. Stain-free gel is provided as loading control. b Protein-protein interaction analysis using STRING functional annotation database on the predicted enriched proteasome, chaperones and cardiac proteins identified in β-cat^Δex3 exosomes including CRYAB. c Representative confocal images of immunofluorescence stainings of Neuro2a cells that were exposed to β-cat^Δex3 and control derived-cardiac exosomes and stained for CRYAB. Perinuclear staining (red arrows) and increased protein accumulation (white arrows) was observed in recipient cells (n = 3, technical replicates). d Representative confocal images of immunofluorescence staining of Neuro2a cells that were exposed to carboxyfluorescein succinimidyl ester (CSFE)-ex vivo labeled exosomes from β-cat^Δex3 hearts, stained with Tubulin III (TUBIII) and LAMP1 (n = 3, technical replicates). The white box (i) indicates the region that is depicted at the right side showing the different stainings (ia-id). Hoechst33342 was used for nucleus visualization. Scale bar = 20 µm.