Fig. 2

Fig. 2 Catecholaminergic neurons are reduced in ascl1a, ascl1b double mutants. (A–X) th WISH of 96 hpf embryos. Lateral views (A–D) and dorsal views (E–Y) of wildtype, single ascl1a and ascl1b mutant, and double mutant embryos. Anterior is to the left. Double mutant embryos (D) show a severe reduction or absence of NA cell groups (AAC, LC, MO, sym) when compared to wildtype or single mutant embryos. The LC NA neurons are also lost in ascl1a single mutants (B). Pretectal neurons (E–H) are strongly reduced in double mutants (arrowheads) in comparison to wildtype. Subpallial DA neurons (I–L) are reduced in single and double mutants (arrowheads) compared to wildtype with the strongest reduction in double mutants. Olfactory bulb neurons (M–P) are reduced in ascl1a single mutants and double mutants (arrowheads). In the prethalamus and hypothalamus (Q–T) only DAC1 (non-filled arrowheads), DAC (filled arrowheads) and DAC7 (arrows) are reduced in double mutants, whereas DAC2, 4, 5 and 6 are not affected. The magnification of cluster DAC3 (U-X, from overviews Q-T) highlights the observed reduction (arrowheads). For numbers of analyzed embryos see Supplemental Table S2. Abbreviations: AAC, arch associated cluster; DAC, DA cluster; Hyp, hypothalamus; LC, locus coeruleus; MO, medulla oblongata; OB, olfactory bulb; Po, preoptic region; Pr, pretectum; Pth, prethalamus; Sp, subpallium; sym, sympathetic neurons. Scale bars: 50 μm in A for A-A and in E for E-T; 25 μm in U for U-X.