Figure 5

Erk1/2 Activation blocks both spontaneous and induced differentiation. (A) Cell number quantification for each differentiation marker (Tuj1, GFAP or RIP) in proliferating adult NSC culture in the presence of FGF-2 (20 ng/ml) and with U0126 or U0124 (2.5 μM) (n = 6; *: P < 0.01, Student's t-test). (B) Cell number quantification for each differentiation marker (Tuj1, GFAP or RIP) in adult NSCs expressing MEK1-WT, DN, or CA at 6 days after the induction of differentiation with RA (0.5 μM) and FBS (0.5%) (n = 3; *: P < 0.01, Student's t-test). (C) Western blot analysis of neuronal marker Tuj1 expression in adult NSCs expressing MEK1-WT, DN, or CA under the medium only, FGF-2 supplemented and normal differentiation with RA (0.5 μM) and FBS (0.5%) conditions. (D) Semi-quantitative RT-PCR analysis on the induction of NeuroD, CyclinD2 and Jag1 genes in adult NSCs expressing MEK1-WT, DN, or CA under the differentiation condition.