Fig. 8. Polyclonal antibody SuperBUGS labels axons in a gradient that is highest towards the growth cone in cultured cerebral cortical neurons. (A-C) Low power, confocal fluorescence images of cerebral cortical cultures from an E16 mouse labelled with phalloidin (A), which labels actin filaments, and immunolabelled with a phosphate-independent MAP1B antibody (B) and pAb SuperBUGS (C). Despite the distribution of MAP1B throughout the neuron, pAb SuperBUGS only labels the axon (minor processes are unlabelled) and in a gradient that is highest towards the growth cone. (D-F) High power, confocal fluorescence images of a growth cone from an E16 mouse cerebral cortical culture labelled with phalloidin (D), which labels actin filaments, and immunolabelled with an antibody against tubulin (E) and pAb SuperBUGS (F). Polyclonal antibody SuperBUGS partly colocalises with microtubules but also extends into the P-domain of the growth cone where the filamentous actin is concentrated. (G-I) High power, confocal fluorescence images of a growth cone from an E16 mouse cerebral cortical culture labelled with phalloidin (G), which labels actin filaments, and immunolabelled with an antibody against tubulin (H) and pAb BUGS (I). Polyclonal antibody BUGS partly colocalises with microtubules but also extends into the P-domain of the growth cone, where the filamentous actin is concentrated. Bar, 40 µm (A-C); 5 µm (D-I).