Neuronal differentiation of mouse embryonic stem cells and expression of Wnt and Wnt component genes. (a)–(e) Using N2B27 medium, 46C ES cells (Sox1-promoter-GFP) were differentiated to neuronal cells for 14 days. GFP in 46C ES cells was expressed during neuronal differentiation for 6 days ((a) phase contrast, (b) Sox1-GFP), and neurite outgrowth increased during neuronal differentiation for 8 days (c) and 14 days ((d) phase contrast, (e) MAPII (red), DAPI (blue)). (f) RT-PCR results of stem cell marker, Wnt, and Wnt signaling components during neuronal differentiation. During neuronal differentiation, RNA levels of many Wnt and Wnt signaling components were changed. Scale bars, 50 μm.