A–J, Expression of GFP and tdTomato in the PDGFRα-cre-ER; Sox10-GFP/tdTOM double-transgenic embryos. Embryos were treated with tamoxifen from E11.5 to E16.5 (A–E) or from E11.5 to E18.5 (F–J). A, GFP+ OPCs were observed in dorsal cortex at E16.5. B–D, Higher magnifications of three regions outlined in A. E, Statistical analysis of tdTomato+ OPCs (average, 238/section) and GFP+ OPCs (average, nine/section) in the cortex (p = 0.0004608). F, GFP+ OPCs were observed in the dorsal cortex at E18.5. G–I, Higher magnifications of regions outlined in F. J, Statistical analysis of tdTomato+ OPCs (average, 1151/section) and GFP+ OPCs (average, 172/section) in the cortex (p = 0.0000661). K, L, Expression of GFP and tdTomato in E16.5 control (K) and DTG (L) embryos following tamoxifen treatment at E11.5.