Figure 1

Hypothalamic NPVF neurons project to the serotonergic IRa. (A,E) Schematic: 6-dpf zebrafish brain showing location of hypothalamic (Hy) NPVF neurons (green), and the serotonergic superior raphe (SRa, red) and inferior raphe (IRa, magenta). A, anterior; P, posterior; D, dorsal. (B–D) Maximum intensity projection of a brain from a 6-dpf Tg(npvf:eGFP) animal (78 μm thick). npvf-expressing neurons in the hypothalamus project to the serotonergic raphe nuclei (RN) in the hindbrain (bracket). 5-HT immunohistochemistry labels the RN (bracket), as well as serotonergic populations in the ventral hypothalamus (asterisks) and pretectum. The bracketed region in (B–D) is shown at higher magnification in (I–K) as a maximum intensity projection (50.5 μm thick), with a sagittal view shown in (F–H). Single optical sections are shown in Figure 1—figure supplement 1. Scale: 50 μm (B–D), 20 μm (F–H), and 10 μm (I–K).