Fig. 5

Blocking autophagy affects cytoplasmic organization of the regenerating muscle. Fish were myectomized and treated with or without CQ, 5 d later the regenerating muscle was extracted and imaged by electron microscopy. (A) Electron micrography of regenerating muscles without CQ treatment, scale bar: 2 µm. (B, C) High-magnification images of the boxes in (A)and (B)showing the typical sarcomeric structure; scale bars represent 1 µm and 200 nm, respectively. (D) Overview of the regenerating muscle of treated fish, note the high amount of unresolved autophagosomes, scale bar: 2 µm. (E) View of the box in (D)showing an example of unresolved autophagosomes, scale bar: 1 µm. (F, G) High-magnification views of the boxes in (E)revealed that the autophagosomes were filled with undigested cellular debris; scale bars represent 600 nm and 200 nm, respectively. (H, I) In addition to the unresolved autophagosomes, the analysis of the CQ-treated fish revealed that the regenerating muscle contained a high proportion of disorganized sarcomeres (compare to C); scale bars: 200 nm. This was not found in the injured muscles of untreated fish.