Modifications of RhoA pathway components in the injured spinal cords of Nestin-Stat3^−/− mice. (A) Western blotting shows the expression of RhoA in the spinal cords of Nestin-Stat3^−/− mice at 5 dpi is reduced compared with WT mice (n = 5 per group, Mann-Whitney U test). (B) The relative amount of activated RhoA (i.e., RhoA-GTP/total RhoA), assessed by G-Lisa assay, exhibits a nonsignificant reduction in the injured spinal cords of Nestin-Stat3^−/− mice at 5 dpi (n = 6 and 8 mice in WT and Nestin-Stat3^−/− groups). (C) Phosphorylated ERM proteins are found in both reactive astrocytes and nonastrocyte cells in the lesion border area in the spinal cords of injured WT mice at 5 dpi. In contrast, the p-ERM immunosignal is specifically reduced in reactive astrocytes of injured spinal cords of Nestin-Stat3^−/− mice (confocal analysis). Bar, 100 µm. (D) High-magnification, confocal analysis allows visualizing the localization of p-ERM in reactive astrocytes (arrows) and nonastrocyte cells (arrowheads) in WT injured spinal cords at 5 dpi. In contrast, in the injured spinal cords of Nestin-Stat3^−/− mice, whereas the p-ERM signal in nonastrocyte cells is not changed (arrowheads), p-ERM IR is clearly reduced in reactive astrocytes (asterisks). Images shown correspond to a single plane extracted from a 1-µm step Z-stack series. The acquired fields are located at the interface between the lesion center and surrounding reactive astrocytes at 5 dpi. Bar, 20 µm (Videos 2 and 3 display the full Z-stacks). Error bars indicate ±SEM. *, P < 0.05.