Expression was observed in the hermaphrodite DTCs and MLCs as well as in all five classes of motorneurons that exhibit axon guidance defects in
unc-5 mutants (DA, DB, DD, VD, AS). In addition, expression was observed in several classes of neurons in the head that are not visibly affected by
unc-5 mutations. These included 12 sensory neurons of the OLQ, OLL and IL2 classes, and the interneurons RIA, RIH and ASE. Expression of lacZ or gfp transcriptional reporters in the DA, DB and DD embryonic motorneurons was first detected in late stage embryos at about the time when these neurons are known to extend pioneer axons along the epidermis (aka, hypodermis) to the dorsal side. Expression in the DA and DB neurons was transient, and only DD staining persisted into larval and adult stages. The VD motorneurons expressed intensely at this and at later times, while the AS neurons expressed faintly and sporadically.