Fig. 5

Fig. 5

Detailed analysis of Wnt7b expression. (A–B2) Double in situ hybridisation using sonic hedgehog (shh) in red and one Wnt7b paralogue as indicated in purple; lateral views, anterior to the left. (A–A2) Focussing on the brain region we do not observe overlapping expression of either Wnt7b paralogue with shh in the prechordal plate. (B–B2) Wnt7ba is expressed just posterior adjacent to shh expressing cells in the area of the Kupffer’s vesicle (arrow). In addition Wnt7ba is expressed in the region of the proctodeum (arrowhead). (B′) Asterisks indicate the absence of Wnt7bb expression in both the region of the proctodeum and the Kupffer’s vesicle. (C–C2) Frontal views focussed on the telencephalic expression of the Wnt7b paralogues show that while Wnt7ba expression is slightly more pronounced in the dorsal part it does not extend as far ventrally when compared to Wnt7bb expression (brackets indicate comparable areas of the telencephalon). All developmental stages are indicated. di, diencephalon; me, mesencephalon; Tel, telencephalon.