Fig. 2

Expression of disease-linked ribosome biogenesis factors in X. tropicalis embryos. a Expression of all four genes was detected in the 4-cell and gastrulating embryo. Signal was strongly detected in the neural folds at stage 16 and in the migrating neural crest at stage 22. b At later stages expression of all factors was detected in the facial primordia and developing brain. Note the restricted expression at the mid–hindbrain border and forebrain. Expression was also typically detected in ventral mesoderm and hypaxial muscle precursor cells. utp4 mRNA was strongly detected at the site of the future liver. c Red lines labeled a*, b* and c* in diagrams of stage 10 and 28 embryos represent the planes of section shown in a and b