Fig. 4

Characterisation of tissue-specific expression patterns of CNEs from the RCN1 to PAX6 intergenic region. (A) Schematic overview of the region with the positions of the ancient gnathostome CNEs indicated by ellipses. The agCNEs (orange) and the chick-mammalian specific CNEs (purple) characterised in this figure are highlighted. (B) Representative reporter transgenic embryos are shown for agCNE1-5 and for the less deeply conserved E-250 and E-72 elements. Only background signal is seen with the E-250 and E-72 fragments. agCNE1 drives expression in the trigeminal ganglia and dorsal spinal cord neurons. agCNE2 transgenic embryos show signal in forebrain, olfactory bulbs and placodes and hindbrain. Expression from agCNE3 is seen in the olfactory placodes and olfactory bulbs with weak expression in hindbrain in some of the lines. In contrast agCNE4 shows strong hindbrain specific expression. agCNE5 shows consistent expression in the forebrain, with hindbrain expression in some lines.