Using NTera-2, it was found that the dynamic phosphoproteomic profile was observed after induction toward astrocyte differentiation. We found that there was a slightly increased in the overall phosphoproteomic profile levels at day 14 after induction for differentiation. In contrast, the upregulation and downregulation levels of phosphoproteomic profile increased dramatically and Figure 2 . Translocation of olig2, activation of STAT3 signaling and STAT3-p300 complex formation, and loss of Sin3A after differentiation. A. Immunofluorescence staining for olig2 (red, upper panel), Hoechst dye (blue, middle panel), and merged images (bottom panel) are shown for undifferentiated control NTera-2 cells and NTera-2 cells 21 days after differentiation. Magnification 4006. B. STAT3 activation was examined with a specific antibody against phosphorylated STAT3, and total levels of STAT3 in lysates from undifferentiated NTera-2 cells and NTera-2 cells 21 days after differentiation (left panel) were determined. C. Lysates from cells similarly transduced were subjected to immunoprecipitation with an antibody against STAT3 and then were also probed with an anti-p300-specific antibody (right panel). doi:10.1371/journal.pone.0022018.g002 more than 50% phosphorylation sites have differential levels after stimulation for 21days, suggesting the dramatic change in phosphoproteomic pattern.