Prepattern established by RhoGEFs is required for correct localization of Rho family GTPases. (A–D) Localization of ChFP-Rho1 colabeled with sGMCA in control (A–A″), RhoGEF2^RNAi(1) (B–B″), pbl^RNAi(1) (C–C″), and RhoGEF3^RNAi(1) (D–D″) mutant backgrounds. (E–H) Fluorescence intensity profiles across the wound area in (A″–D″). (I–L) Localization of GFP-Rac1 colabeled with sChMCA in control (I–I″), RhoGEF2^RNAi(1) (J–J″), pbl^RNAi(1) (K–K″), and RhoGEF3^RNAi(1) (L–L″) mutant backgrounds. (M–P) Smoothened fluorescence (Fluor.) intensity (arbitrary units) profiles derived from averaged fluorescence intensity values over a 10-pixel width across the wound area in the embryo shown (I″–L″). Error bars represent the 95% confidence interval. (Q–T) Localization of ChFP-Cdc42 colabeled with sGMCA in control (Q–Q″), RhoGEF2^RNAi(1) (R–R″), pbl^RNAi(1) (S–S″), and RhoGEF3^RNAi(1) (T–T″) mutant backgrounds. (U–X) Fluorescence intensity profiles across the wound area in (Q″–T″). Time after wounding is indicated. Bars, 20 µm.