unc-4 mutations do not affectunc-17-cha-1 promoter:: gfpexpression. The 3.2 kb unc-17-cha-1promoter:: gfp reporter gene is expressed in virtually all cholinergic neurons. A, B, Lateral view of GFP-positive DA and DB motor neurons in both wild-type andunc-4(e120) L1 larvae. C, D, Lateral view of L2 stage larva showing equivalent levels of GFP expression in postembryonically derived VA and VB motor neurons in wild-type and unc-4(e120) animals. Thearrowhead denotes AS motor neurons that are seen in both wild-type and unc-4 animals. Asterisksmark gut autofluorescence. Scale bars, 10 μm.