Figure 5.

Early spt expression in the developing CNS and somites. A and C show lateral views of two embryos at 16 hpf. Rostral is up and dorsal is to the right. B shows a dorsal view of the embryo in A. Rostral is up. White arrowheads indicate the most rostral somitic domain of spt transcription visible. Black arrowheads indicate the most rostral neural cell expressing spt. For B, the light source was concentrated behind the yolk to give greater visibility of staining. All images are composites of smaller images. Scale bars equal 100 μm.