Figure 8.

deltaA and deltaD affect expression of DA precursor and differentiation genes. The expression of transcription factors involved in DA and neuroendocrine precursor development and differentiation was analyzed at 30 hpf (A–H) or 16 hpf (I–T) in the offspring of fish carrying dla^hi781, dld^tr233, or mib^ta52b mutant alleles as indicated in the panels. All diencephalic expression domains of both otpa (A–D) and sim1a (E–H) were enlarged in dla^hi781 (B, F), dld^tr233 (C, G), and more severely in dla^hi781/dld^tr233 double mutants (D, H) compared with control siblings (A, E). In contrast, in dla^hi781/dld^tr233 double mutants, sim1a expression was reduced in the mesencephalon (H, arrowhead). All arrows point at the posterior tubercular area. A higher number of cells expressing otpa (I–L), sim1a (M–P), and dlx5a (Q–T) was detectable already at 16 hpf in dla^hi781 (I, J, M, N, Q, R) and mib^ta52b (K, L, O, P, S, T) mutants. All images are dorsal views, anterior left. A–H are z-projections of transmitted light image stacks. Scale bars, 100 μm.