Fig. 2

Expression of ppp2r3b in zebrafish. (A–C) In situ hybridisation showing expression of ppp2r3b at 24 hpf. High-power view showing expression in somites (B) and rostally (C). (D) Transverse section of 36 dpf zebrafish stained with Mallory’s trichrome. Arrows indicate examples of myosepta separating bundles of muscles fibres. (E) Similar section to (D) showing expression of ppp2r3b at 36 dpf. Arrows indicate myosepta that define muscle bundles outlined in red (mb, F). (G, H) Higher magnification images whereby arrows indicate myosepta, and arrowheads indicate staining around individual muscle fibres. Dashed boxes show the location of the insets which individual muscle fibres at higher magnification. (I) Inset from F showing mineralised bone (b) within vertebral centra showing expression of ppp2r3b in squamous chordoblast cells (arrowheads). Asterisks label individually staining cells of distinct morphology. Scale bars are 200 µm in (A, B); 40 µm in (C); 150 µm in (D–H); 12 µm in (I).