Fig. 2. Characteristics of median neuroblast lineage (lineage 0). (A) A thick section projection of confocal slices showing the Neurotactin scaffold between the ventral and intermediate commissures. The neurite bundle from lineage 0 projects to the level of the aI commissure up through T2, but is redirected to the pI commissure in T1. Posterior ventral arch (pVA) is labeled in T3 but is also present in T2 and T1. `0' identifies the ventral base of bundle 0 in each segment. (B-D) Ventral views of projections of full lineage 0 clones in the (B) S3, (C) T1 and (D) T3 neuromeres. Diagrams show the trajectory of the neurite bundle in the Neurotactin scaffold, and the position of the lineage 0 cluster relative to the other clusters in the hemisegmental array. Commissure abbreviations as in Fig. 1