Inhibition of neurite formation during late neuronal differentiation by GSK3β inhibitor. (a) Diagram of MeBIO (0.75 μM) or BIO (0.75 μM) treatment during late neuronal differentiation of 46C ES cells. (b)–(e) Cells cultured according to the diagram for 15 days were stained with MAPII antibody. Neurite formation was elevated by BIO treatment from days 4 to 7 (c), whereas it was reduced by BIO treatment from days 4 to 15 (d). (e) Cells were cultured with BIO from days 7 to 10 and cultured with MeBIO for 7 days after replating, followed by staining with MAPII antibody. Scale bars, 100 μm.