Fig. 2

Figure 2. Detection of neuromast hair cells and supporting cells in 5 dpf larvae. (A,B) Confocal images of neuromasts from a 5 dpf control larva and 5 dpf larva treated with 10 μM SP600125. The neuromast hair cells in the transgenic line Brn3c:mGFP were detected by GFP visualization (green), supporting cells were detected by Sox2 (red), and proliferating cells were detected by BrdU (white). Higher magnification of hair cells and supporting cells of the neuromast taken from z-stacks show that hair cells and supporting cells in untreated controls and SP600125-treated animals had no observable morphological differences though there were fewer GFP-positive and Sox2-positive cells in the neuromasts of larvae treated with SP600125. The number of BrdU-labeled cells is much larger in control than in SP600125-treated larvae. Scale bar = 10 μm. (C,D) Quantification of hair cells and supporting cells in the neuromast (NM) for each experimental condition. (E–G) Quantification of replicating cells in the neuromasts for each experimental condition. SP600125 treatment decreased the numbers of BrdU-positive cells, the ratio of BrdU-positive hair cells, and the ratio of BrdU-positive supporting cells in neuromasts. The first four neuromasts along the body, L1–L4, were recorded on one side of each fish [one-way ANOVA; GFP+ cells: F_{(3, 112)} = 237.5, p < 0.001; Sox2+ cells: F_{(3, 112)} = 102.5, p < 0.001; BrdU+ cells: F_{(3, 112)} = 134, p < 0.001; BrdU+ HCs: F_{(3, 112)} = 89.7, p < 0.001; BrdU+ SCs: F_{(3, 111)} = 32.08, p < 0.001]. Bars are mean ± SD. n = 36 neuromasts in control, n = 28 in 5 μM SP600125-treated neuromasts, n = 24 in 10 μM SP600125-treated neuromasts, and n = 28 in 15 μM SP600125-treated neuromasts. *p < 0.05, significant difference when compared to control larvae; ***p < 0.001, highly significant difference when compared to control larvae.