FIGURE 4.

YAP nuclear transport by stretch is abrogated by ROCK inhibitor. (A,B) MSCs were stretched under a ROCK inhibitor (Y27632) for 1 h, and YAP nuclear localization was assessed by immunostaining of YAP (green) and DAPI (blue). The stretch induction of YAP nuclear import was suppressed by Y27632. This was assessed with the percentage cells positive for YAP nuclear localization, as quantified from the nuclear/cytoplasmic YAP fluorescent intensity ratios (n of 36 cells or more per each condition) using the methods described in Figure 1B. Scale bar = 20 μm. (C,D) YAP expression was assessed by western blotting for nuclear and cytoplasmic extracts with appropriated loading controls, lamin B1 for the nuclear fraction and GAPDH for the cytosolic fraction (n = 3). Throughout the experiment, the cases without Y27632 were tested under the same amount of DMSO used in Y27632 inhibitor cases as a delivery vehicle. NS: non-significant, *: p < 0.05, **: p < 0.01, ***: p < 0.001.