Fig. 7. Impairment of Ash1a and of Ngn1 activity affects both photoreceptors and projection neurones. Dorsal views of brains showing expression of onecut and opsin in wild-type (WT) and single ash1a, ngn1 or double-morphant embryos. Probe and stage are indicated on the left and `genotype' above. Both markers were affected following the impairment of Ash1a (B,D,H) or of both Ash1a and Ngn1 activity (F,J). Scale bar: 15 µm.