Fig. 4

Stable and bicistronic expression of Tomato and GFP fluorescent proteins in differentiated muscle cells following chick limb somite electroporation with a myosin light chain promoter. a Forelimb somites of E2.5/HH15 chick embryos were electroporated with the PT2AL-MLC-Tomato-T2A-GFP stable vector containing the Tomato-T2A-GFP cassette under the control of the myosin light chain (MLC) promoter. The MLC promoter drives gene expression in differentiated muscle cells. Six days after electroporation, at E8.5, forelimbs were collected for wholemount visualisation (b–d) or immunostaining on transverse limb sections (e–j). Most of the GFP+ nuclei were surrounded by a Tomato + sarcolemma (e–g, arrowheads). h–j GFP+ nuclei were never observed in Pax7+ cells. Scale bars = 50 μm