Fig. 2. _v6 integrins are required for the reinforcement of FN-cytoskeleton bonds at the leading edge of the growth cones. (A,B) Function-blocking antibodies against ₅₁ and _v3 integrins had no effect on binding and the reinforcement of FN-coated beads, but blocking of the _v and _v6 integrins reduced binding and reinforcement to the background levels (A,B). Localization of RPTP and _v6 integrin in growth cones was ECM-specific. Both RPTP and _v6 were localized to the leading edge of growth cones in neurons plated on FN-coated glass (C,D). On LN, RPTP was localized to the growth cones, whereas _v6 integrin was expressed at low levels along the axons and in the growth cones (E,F). Insets provide image of the entire neuron. Bars 5 µm. (G) Fluorescence intensities of the RPTP and _v6 signals were quantified, the data were normalized against nuclear fluorescence intensity and are presented as the mean ± s.e. for at least 20 representative neurons.