Fig. 7
OXR1 impacts midbrain development by shaping histone arginine methylations. a Representative bright-field images (40x) show the progression of midbrain organoids, derived from healthy control (CTRL) or and patient (OXR1ΔEx18) iPSCs. The starting cell number of each clone is indicated (100% refer to 10,000 iPSC cells per microwell of Aggrewell-800 plate on day 0). After midbrain patterning, OXR1ΔEx18 c2 showed less midbrain organoids generated at day 5. b Immunohistochemical analyses of midbrain organoids at day 20 and day 50 using antibodies specific for FOXA2 (magenta, the marker of midbrain floor plate/progenitor) and TH (yellow, the marker of dopaminergic neurons). c Immunohistochemical analyses showing Ki67+ proliferating cells (green) in the VZ of midbrain organoids at day 20. The percentage of Ki67+ cells in progenitor zones (VZ) was quantified. CTRL, n = 9 organoids; OXR1ΔEx18, n = 6 organoids. d Immunohistochemical analyses showing transient expression of EN2 (the marker of mid-hindbrain boundary) in midbrain organoids at day 20. e Immunohistochemical analyses showing the spatial–temporal distribution of H4R3me2s in midbrain organoids at day 50. The average expression of H4R3me2s in each cell was quantified in each vertical position bin (lower left). The normalized abundance of H4R3me2s+ cells in each bin was calculated as in (Fig. 6d). CTRL, n = 23; OXR1ΔEx18, n = 23 from two independent batches. Values represent mean ± SEM, *p < 0.05, **p < 0.01, ***p < 0.001, Student’s t test. In all confocal images, the scale bar is 60 μm and the nuclei were visualized using DAPI (blue)