Table 1.

Effects of hedgehog, FGF8, and Nodal pathway mutants on the formation of the main dopaminergic and noradrenergic groups in the zebrafish CNS

Nodal signaling Hh signaling Hh plus FGF8 MHB organizer-FGF8
MZsurZsuroepcycsyusmusmu/aceacespgnoiace/no
Ventral diencephalic DA neurons
    24 hpf - (+) (o) (o) + + + + (+) + (+)
    48 hpf - (-) (o) (o) #/- # # - (+) - (-)
    72 hpf N.D. - o o #/- #/- N.D. + - + (-)
Pretectal CA neurons
    72 hpf N.D. + o o -/o -/o N.D. + (+) + (+)
Locus coeruleus CA neurons
    48 hpf N.D. + (+) (+) (+) (+) o o (o) o (o)
    72 hpf N.D. + + + (+) (+) N.D. o o o (o)
Medulla oblongata CA neurons
    48 hpf N.D. (+) (+) (+) (+) (+) (+) + (+) + (+)
    72 hpf N.D. (+) + + (+) (+) N.D. + + + (+)
Amacrine DA neurons
    72 hpf N.D. (+) + o -/o -/o N.D. + (+) N.D. N.D.
Olfactory bulb CA neurons
    72 hpf N.D. + o -/o + + N.D. + + + +

  • +, Not affected; -, reduced; o, absent; -/o, highly reduced or absent; #, altered morphology of the neuronal cluster; N.D., not determined; symbols in brackets, data not shown in figures; hpf, hours postfertilization.