Fig. S5

pax3a:GFP and Pax7-expressing adult zebrafish satellite-like cells proliferate after injury. (A) Schematic of acute (“pulse”) EdU labeling experimental procedure, in which mechanical injury is performed by a single needle-stick into tail skeletal muscle, followed at 4 or 5 dpi by intraperitoneal EdU injection and fixation 4 hours later. (B) Expression of Pax7 and pax3a:GFP and EdU incorporation at the injury site at 5 dpi. (C) Enlarged view from boxed region in B shows pax3a:GFP and Pax7 double positive cells at the injury site, some of which are EdU-positive (yellow arrowheads) and others EdU-negative (white arrowheads). Purple arrowheads indicate pax3a:GFP+ cells that are Pax7-negative, brown arrowheads indicate cells weakly expressing pax3a:GFP that are EdU-positive, and the pink arrowhead indicates a cell that is EdU-positive only. (D-F) pax3a:GFP, acute EdU, and Pax7 labeling at 4 dpi. (G) Overlay of channels from D-F; quantification shows that a majority (94%) of Pax7-positive cells are pax3a:GFP-positive (544/575 total cells counted). The arrowheads define cells as described above. Cells that are Pax7-positive and pax3a:GFP-negative are indicated by blue arrowheads. Scale bar in B is 75 μm and in F and G is 30 μm.