Fig. 1. max-2 is required for ventral cord commissural motoneuron guidance. (A,B) A schematic of the DD and VD cell bodies (solid dots) and commissural axons in wild-type (A) and max-2(cy2) (B) animals. In each panel, a cross-section is on the left and a lateral view of the entire animal is on the right. (C-H) Confocal images of representative animals: anterior is to the left and dorsal is up. (C,D) First larval stage (L1) animals before the formation of the VD neurons. In wild-type animals (C), the dorsal commissures of the DD neuron all reach and enter the dorsal cord, but the DD commissures in max-2(cy2) animals (D) often fail to reach the dorsal cord. (E,F) L4 animals, after the migration of the VD commissures. In wild-type animals, all commissures reach the dorsal cord (E). In max-2(cy2) animals, many commissures fail to reach the dorsal cord (F). All animals in C-F are in the oxIs12[Punc-47::GFP]X background to visualize the DD and VD motoneurons. (G,H) max-2 animals have defects in the DA and DB motoneurons. Shown here are examples of commissural axons in wild-type (G) and max-2(cy2) animals (H) at early L4 stage. All animals in G,H are in the evIs82[Punc-129::GFP] background to visualize the DA and DB neurons. Scale bar: 10 µm.