FIG. 5.

CDO promotes neuronal differentiation of C17.2 neural progenitor cells. (A) Western blot analysis of CDO, NeuroD, β-tubulin III, nestin, and cadherin expression in C17.2 cells during a time course of neuronal differentiation. Subconfluent cells were shifted to DM, and cells were harvested at the indicated time points. (B) Western blot analysis of CDO, nestin, β-tubulin III, and cadherin expression by C17.2 cells transiently transfected with either control (−) or CDO (+) expression vectors. Transfection efficiency was 40 to 50%, with similar results in three independent experiments. (C) Immunostaining for β-tubulin III expression by C17.2 cells transiently transfected with EGFP expression vector and either control (pBP) or CDO expression vectors. Arrowheads indicate Tuj1-negative transfectants, and arrows indicate Tuj1-positive transfectants. (D) Quantification of four independent experiments shown in panel C. The y axis represents the percentage of TuJ1-positive cells. (E) Western blot analysis of CDO, β-tubulin III, and cadherin expression by C17.2 cells transiently transfected with control siRNA vector (−) or pSil/CDO RNAi vector (+). Similar results were obtained with three independent experiments. (F) Immunostaining for β-tubulin III expression by C17.2 cells transiently transfected with expression vectors for GFP, Ngn1, and E12 and as indicated with combinations of pSil, pSil/CDO, pBP, and pBP/CDO. Arrowheads indicate Tuj1-negative transfectants, and arrows indicate Tuj1-positive transfectants. (G) Quantification of four independent experiments shown in panel F. The y axis represents the percentage of TuJ1-positive transfectants.