Fig. 2

Transverse section of an embryo at 90 % epiboly at the position indicated on top on a sagittal section (anterior to the right). Anteriorly expression is only observed in prechordal plate mesoderm (A) posteriroly expression is also observed in neurectoderm with an expression pattern suggesting an induction of gsc expression in ventral neurectoderm (Thisse et al, 1994)

Fig. 2 Expression is observed from shield to 60% epiboly in prechordal plate mesoderm. At 70% expression is maintained in prechordal plate and starts in ventral neurectoderm. From 80 to 100% epiboly expression is strong in prechordal plate and in ventral neurectoderm (presumptive ventral diencephalon. At the end of gastrulation expression is also observed in presumptive telencephalon (anterior edge of the neural plate).