Figure 2

zic2a and zic2b are co-expressed with aldh1a2 and cyp26a1 in the early embryo. 90% epiboly embryos were processed for in situ hybridization for aldh1a2, cyp26a1, zic2a or zic2b, and subsequently mounted in JB-4 resin and cut into 7 μM sections on a microtome. aldh1a2 expression is clearly limited to the hypoblast (A), while cyp26a1 is present in the epiblast (B). In contrast, zic2a and zic2b each show broad expression across the germ layers (C,D).