Effect of ROCK and mDia mutants on the TPA-induced reorganization of the actin cytoskeleton in MDCK cells. pEF-BOS-myc-V14RhoA (a–d), pEF-BOS-myc-C3 (e and f), pCAG-myc-ROCK-Δ1 (g–j), pCAG-myc-ROCK-KDIA (k and l), pEF-BOS-myc-mDia-ΔN (m–p), or pEF-BOS-myc-mDia-ΔRBDΔC (q and r) were microinjected into the nuclei of MDCK cells. At 10 h after the microinjection, the cells were stimulated with 100 nM TPA for 15 min (a, b, g, h, m, and n) or 2 h (c–f, i–l, and o–r) and fixed. The cells were double stained with rhodamine-phalloidin (a, c, e, g, i, k, m, o, and q) and the anti-myc mAb (b, d, f, h, j, l, n, p, and r) and analyzed at the basal levels using confocal microscopy. The results shown are representative of three independent experiments. Bars, 10 μm.