(A–D) Cross-section of E3 transgenic embryo stained for the indicated markers, showing the expression of the transgene throughout the primary myotome. (A) GFP-CAAX, (B) NLS-mCherry, (C) Pax7, (D) Merge. Insets in (A–D) Magnifications of the regions indicated in (A–D) showing the cellular localisation of the markers. (E–H) E5 Transgenic embryo showing GFP-CAAX (E) and NLS-mCherry (F) in the transition zone (TZ, arrow) where progenitors from the dermomyotome translocate to elongate and differentiate. (I–K) E5 embryos showing strong and specific expression of the muscle-specific reporter in somites (arrowheads). In this quail line, transgenic embryos can be selected at hatching by tηε GFP expression in lens due to the CrystallGFP minigene (arrows). (H–J) E7 transgenic embryo showing muscle-specific expression of the transgene in the head, limbs and trunk.