FIGURE 1.

Cyclic stretch loading induces YAP nuclear translocalization in MSCs. C3H10T1/2 murine MSCs were unstretched (control) or stretched, and assessed for immunostaining and western blotting for YAP. (A,B) Immunofluorescence of YAP (green) and DAPI (blue). Assessment of cells showing nuclear YAP localization was conducted using the NIH ImageJ analysis of YAP immunofluorescence. For this, the ratio of nuclear/cytoplasmic YAP fluorescent intensity was quantified for each cells. Then, the average and standard deviation of the YAP intensity ratios of the unstretched control cells were obtained. In case a cell showed a YAP nuclear/cytoplasmic fluorescent intensity ratio greater than the average plus one standard deviation of the control, then the cell was determined as to exhibit YAP nuclear residency. Finally, the percentage of cells with YAP nuclear localization was obtained (n of 30 or more cells per each condition). Scale bar = 20 μm. (C,D) Western blot analysis of nuclear and cytoplasmic protein extracts from MSCs stretched for 1 h. Anti-lamin B1 was used as a loading control for the nuclear fraction and anti-GAPDH for the cytosolic fraction (n = 3). *: p < 0.05, **: p < 0.01, and ***: p < 0.001 compared with control.