Figure 3

Chicken Embryo Electroporation. (A) Embryos were electroporated at Hamburger and Hamilton stage 10 and collected 24 h later. A CMV-GFP plasmid was always used as positive control of the electroporation and only embryos showing an expression pattern as shown were kept. Embryos electroporated with beta-globin_LacZ (BGZ40) plasmid alone or in combination with EMX2 in pCMV6-Entry (CMV-EMX2) were used as negative controls (not shown). (B) A 4 kb genomic fragment of the teneurin-1 promoter was cloned into the reporter plasmid beta-globin-LacZ (ten-1BGZ40) and electroporated alone (WT control) or in combination with CMV-EMX2 plasmid (WT + EMX2). A mutated version of ten-1BGZ40 lacking a potential EMX2 binding site (mut ten-1BGZ40) was electroporated alone (data not shown) or in combination with CMV-EMX2 (Mut + EMX2). (C) Electroporation results are summarized in stacked columns. Data are represented as percentile of the total number of electroporated embryos (n = 16 for the WT construct and n = 26 for the mutated construct) and are classified according to three levels of reporter expression: strong staining, medium staining and no or weak staining.