Fig. 1. Dynamics of hindbrain neurogenesis. (A-D) Transverse sections through the hindbrain at the level of rhombomeres 4 and 5 in HuC-GFP-positive embryos. The GFP fills both neuronal cell bodies and processes. Broken lines in B-D indicate the boundary between the mantle zone and the marginal zone. A distinct T-shaped ventricular zone is obvious at 36 hpf as an area devoid of HuC-GFP expression and this decreases dramatically by 48 hpf. Dorsal is to the top. (E) Horizontal confocal section through a living HuC-GFP-positive embryo stained with Texas Red Bodipy Ceramide to outline cell profiles. Arrowheads indicate the boundary between rhombomeres 3 and 4 and arrows indicate the boundary between rhombomeres 5 and 6. The embryonic midline is highlighted by a broken line. (F) Graph documenting numbers of neurons and non-neurons in rhombomeres 4 and 5 throughout embryogenesis. The red curve highlights the increase in neurons and the blue curve indicates the number of non-neuronal cells. Scale bars: 50 µm.