Figure 1

Schematic summary of the regenerative processes after cryoinjury in the zebrafish heart. (A) Illustration of the anatomy and histology of an intact zebrafish heart. The ventricle comprises a trabecular myocardium (beige) that is surrounded by a thin layer of a compact myocardium (orange). (B) Illustration of the main cellular processes after cryoinjury during the regeneration time. The prominent events are written in the boxes and linked to the specific periods after cryoinjury. The schematic heart sections were based on AFOG histological staining that visualizes the myocardium in beige/orange, collagen in blue and fibrin-like material in red. The injury zone switches from red staining at 4 and 7 dpci, to blue collagen staining after 7 dpci. At the bottom, the rectangular graph depicts a progressive replacement of the wound with a new myocardium. During this time, the wounded tissue undergoes remodeling, starting from the inflammatory state (red gradient) followed by collagenous scar deposition (inverse blue gradient).