Figure 6

Loss of lmx1b.1 and lmx1b.2 changes the spatial organization of CA cell bodies in the vDC and the hindbrain. (A) Embryos injected with control morpholino display a normal development of DA neurons in the vDC. (B) Embryos injected with both MOlmx1b1 and MOlmx1b2 similarly generate th expressing cells in the vDC, but they are dispersed towards lateral positions. (C, D) Confocal analysis of anti-TH immunostaining shows that vDC group 3 neurons develop normally in morphant embryos (D, arrow) compared to controls (C), while group 1 neurons are somewhat reduced (D, arrowhead). Confocal z-projections of 80 μm (C) and 74 μm (D) are reported. (E) Control morphant embryos form noradrenergic neurons in the area postrema (arrow), while (F) in the same area lmx1b.1 and lmx1b.2 double morphants show a gap of th expression (white arrows). Surprisingly, double morphants frequently exhibit ectopic th-expressing cells in the hindbrain (F, black arrow). (G-H) Analysis of pitx3 expression in control (G) and lmx1b.1/2 morphant embryo (H) at 28 hpf. The diencephalic expression domain of pitx3 is strongly reduced in MOlmx1b1/2 injected embryos. In addition, the most ventral diencephalic domain of nr4a2a expression is reduced in 48hpf morphant embryos (J, compare to I; arrows). A-H: dorsal views; I-J: lateral views. Anterior is to the left. Scale bars in A are for A-B, E-F, in G for G-H and in I are for I-J: 100 μm; scale bar in C is for C-D: 50 μm.