Extended Data Fig. 3. Summary of LacZ expression experiments.

(a-i) Replicate embryos from the lacZ reporter injections as indicated in schematic in Fig. 4a. (a) cRE1, (b) cRE3, (c) cRE2, (d) cRE1+cRE2, (e) cRE2+cRE3, (f) cRE1+cRE2*A, (g) cRE1+cRE2*B, (h) cRE2*A, (i) cRE2*B. Shown are all embryos up to a maximum of 10 per genotype, with text denoting embryos >10. ‘S’ and ‘T’ indicate embryos with single or tandem transgene insertion, respectively. Tandem insertions show stronger signals but less specificity than single insertions. White Single (WhS) and White Tandem (WhT) indicate embryos carrying single or tandem transgene insertion, respectively, that do not show β-galactosidase coloration. Embryos have an average crown-rump length of 6 mm. Scale bars in (a) = 500μm for the whole embryo (left) and dorsal hindbrain view through 4th ventricle (right) images and apply to (a-i) as approximate measurements.