Fig. 1. rho3 affects CNS midline repulsion of tracheal ganglionic branches (GBs). (A-F) Three dimensional confocal reconstructions of late stage16 embryos double-stained to reveal the tracheal lumen (by mAb2A12, A-F in red) and longitudinal fascicles (by mAb1D4, B, E in green) or CNS glia (with the exception of midline glia, by anti-Repo C, F in green). All panels show ventral views, anterior towards the left. In wild-type embryos, GBs (A, red) and longitudinal fascicles (B, green) never cross the midline. In rho3, an average of two GBs per embryo cross the midline (D-F, arrows). In the same embryos the longitudinal fascicles appear unaffected (green in E and compare with B), as does the pattern of glial cells (F, compare with C). Scale bar: 20 µm.