FIGURE 5:

The effect of ROCK-1 inhibitor on filopodial assembly and SV clustering. The role of Rho GTPase signaling was further tested using Y27632, which inhibits the RhoA effector ROCK-1. (A–C) GFP-neurons developed filopodia and SV clusters along axons, and treatment with Y27632 (A′–C′) increased axonal filopodia and SV clustering in these neurons. (D–F) WTp120 expression by itself increased filopodial formation and SV clustering in neurons, and this was not further elevated by treatment with the inhibitor (D′–F′). (G–I) Δp120 expression inhibited filopodial growth and SV clustering, and the suppressive effect of Δp120 was partially overcome in the presence of Y27632 (G′–I′). Both J and K quantify these changes in filopodial formation and SV clustering. Mean and SEM are shown. *p < 0.05, **p < 0.01, compared with control; ^p < 0.05, ^^p < 0.01, compared with no treatment.