Fig. 3

Fig. 3

Pax7⁺ nuclei increase in deep myotome. Pax7 (A-E) and EdU (E) labelling in wholemount wt larvae. Single confocal slices of zebrafish larvae in lateral view. A: Flattened dehydrated embryos imaged at the indicated depths (full larval thickness approximately 35 µm). At 3 dpf, MPCs accumulate superficially near VM (white arrows) but are absent deeper within myotome. Xanthophores (purple arrows) are rare and bright. By 6 dpf, Pax7⁺ nuclei appear deep at the VM (red arrowheads) and CP (blue arrowheads). B-D: Numbers of Pax7⁺ nuclei in epaxial somites 16–18 of whole mount larvae increase with age. Mean±S.E.M. The small error bars indicate tight regulation of Pax7⁺ cell numbers. Number of embryos scored is indicated within the columns. E: Co-localization of Pax7 and EdU in MPCs of 4 dpf larva both at VM (white arrowheads) and CP (yellow arrowheads). Vertical myoseptum (VM), central portion (CP), horizontal myoseptum (HM), dorsal edge (DE). Bars 50 µm.