Fig. 1

Expression of transcription factors characterizing DA neurons in the telencephalon. For orientation, a lateral (A, 43 μm projection) and a dorsal (B, 30 μm projection) overview of a 96 hpf zebrafish brain immunostained for TH are shown. The telencephalic DA groups are framed by a circle in A and indicated by arrows in B. In this and in the following figures, TH-immunoreactive cells are always displayed in red and the analyzed transcription factors in green. The dorsalmost telencephalic DA cells express the subpallial markers dlx2a (C–D3) and dlx5a (E–F3), but not tbr1b (G–H3), which labels the dorsal telencephalon. etv1 is expressed only in a subset of subpallial DA neurons (I–J3), but it prominently labels DA cells in the olfactory bulb (K–L3). The images shown in C, E, G, I, and K are overviews of the head of 96 hpf larvae (15–30 μm projections), whereas D–D3, F–F3, H–H3, J–J3, and L–L3 are high magnifications (25 μm projections) of the areas framed in C, E, G, I, and K, respectively. Abbreviations: OB, olfactory bulb; PO, preoptic group; Pr, pretectal group; SP, subpallium; TC, telencephalic cluster; vDC, ventral diencephalic cluster; 1–6; diencephalic DA neuronal groups numbered according to Rink and Wullimann (2002). Anterior is to the left. Scale bars: 50 μm.