Fig. 6

OXR1 impacts cortical development by shaping histone arginine methylations. a Representative bright-field images (40x) showing the progression of cortical organoids, derived from CTRL and OXR1^ΔEx18 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 cortical patterning, the spheroids of OXR1^ΔEx18 clone 2 (c2) usually dissipated by day 5. b Immunohistochemical analyses showing the CTIP2⁺ deep layer neurons (magenta) formed above SOX2-enriched progenitor zones (yellow) of cortical organoids at day 50. c Immunohistochemical analyses showing the Ki67⁺ proliferating cells (green) and cCas3⁺ apoptotic cells (magenta) at VZ/SVZ progenitor zones of cortical organoids at day 50. The bar diagram showing the percentage of Ki67⁺ or cCas3⁺ ells in VZ/SVZ. CTRL, n = 10; OXR1^ΔEx18, n = 15. VZ, ventricular zone; SVZ, subventricular zone. d Immunohistochemical analyses showing the distribution of H4R3me2s⁺ cells in cortical organoids at day 50. The average expression of H4R3me2s in each cell is quantified in each vertical position bin (yellow dash line). The normalized abundance of H4R3me2s⁺ cells in each vertical position bin was calculated as the number of H4R3me2s⁺ cells in a bin / the total number of H4R3me2s⁺ cells. CTRL, n = 23; OXR1^ΔEx18, n = 26 from two independent batches. e Immunohistochemical analyses showing the distribution of H3R2me2s⁺ cells of cortical organoids at day 50. The average expression of H4R3me2s of each cell was quantified in each vertical position bin (lower left). The normalized abundance of H3R2me2s⁺ cells in each vertical position bin was calculated as in (d). CTRL, n = 49; OXR1^ΔEx18, n = 53 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)